The Salado Formation is a thick evaporite sequence located in the Permian Delaware Basin of southeastern New Mexico. This study focuses on the intense diagenetic alteration that has affected the small amounts of clay, feldspar, and quartz washed into the basin during salt deposition. These changes are of more than academic interest since this formation also houses the WIPP (Waste Isolation Pilot Plant). Site characterization concerns warrant compiling a detailed data base describing the clays in and around the facility horizon. An extensive sampling effort was undertaken to address these programmatic issues as well as to provide additional insight regarding diagenetic mechanisms in the Salado. Seventy-five samples were collected from argillaceous partings in halite at the stratigraphic level of the Waste Isolation Pilot Plant (WIPP). These were compared with twenty-eight samples from cores of the Vaca Triste member of the Salado, a thin clastic unit at the top of the McNutt potash zone, and with a clay-rich sample from the lower contact of the Culebra Dolomite (in the overlying Rustler Formation). These settings were compared to assess the influence of differences in brine chemistry (i.e., halite and potash facies, normal to hypersaline marine conditions) and sediment composition (clays, sandy silt, dolomitized limestone) on diagenetic processes. 44 refs., 11 figs., 5 tabs.
The Waste Isolation Pilot Plant (WIPP) is planned as the first mined geologic repository for transuranic (TRU) wastes generated by defense programs of the United States Department of Energy (DOE). Before disposing of waste at the WIPP, the DOE must evaluate compliance with the United states Environmental Protection Agency's (EPA) Standard, Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR Part 191, US EPA, 1985). Sandia National Laboratories (SNL) is evaluating long-term performance against criteria in Subpart B of the Standard. Performance assessment'' as used in this report includes analyses for the Containment Requirements ({section} 191.13(a)) and the Individual Protection Requirements ({section} 191.15). Because proving predictions about future human actions or natural events is not possible, the EPA expects compliance to be determined on the basis of specified quantitative analyses and informed, qualitative judgment. The goal of the WIPP performance-assessment team at SNL is to provide as detailed and thorough a basis as practical for the quantitative aspects of that decision. This report summarizes SNL's late-1990 understanding of the WIPP Project's ability to evaluate compliance with Subpart B. 245 refs., 88 figs., 23 tabs.
Severe nuclear reactor accidents - accidents involving the melting of the reactor core - dominate the residual risk associated with the use of nuclear power. The uninterrupted progression of a severe reactor accident is expected to lead to the expulsion of core debris into the reactor containment. Many safety-significant phenomena may be hypothesized to occur when core debris is expelled from the reactor coolant system. The exact nature of these events depends on whether or not the coolant system is pressurized at the time of melt expulsion and whether or not expulsion is into water. Regardless of what transient events are associated with the initial expulsion of core debris from the reactor coolant system, a protracted period of core debris interactions with the structural concrete of the reactor is expected in most analyses of severe reactor accidents.
Calculations were performed with CTH (a finite difference hydrodynamics code) to evaluate computational capabilities for predicting residual projectile length and position in high velocity penetration events. The calculations simulated selected tests in a set of armor penetration experiments conducted and reported by Los Alamos National Laboratory. The tests and simulations involved penetration of armor ranging from 6.4 to 50.8 mm in thickness by long rod projectiles over a range of velocities from 1.0 to 1.29 km/sec. Comparisons are made between the calculated and measured final projectile lengths and positions, and the sensitivity of the predicted results to target and projectile property variations is investigated. 8 refs., 11 figs., 8 tabs.
This study supports the Waste Isolation Pilot Plant (WIPP) Final Supplemental Environmental Impact Statement and has two main objectives. First, it describes current ideas about the characteristics and potential impacts of the disturbed-rock zone (DRZ) known to develop with time around excavations at the WIPP horizon. Second, it presents new calculations of radionuclide migration within and from the WIPP repository for steady-state undisturbed conditions and for two cases that consider human intrusion into the repository. At the WIPP, the presence of a DRZ has been confirmed by geophysical studies, gas-flow tests, and direct observations. The DRZ will allow gas or brine from waste-emplacement panels to bypass panel seals and flow into adjacent portions of the underground workings unless preventive measures are taken. Revised calculations of the undisturbed performance of the repository indicate that no radionuclides will be released into the Culebra Dolomite within the regulatory period of 10,000 years. The human-intrusion calculations included here assume a connection between the WIPP repository, an occurrence of pressurized brine within the underlying Castile Formation, and the overlying Culebra Dolomite. 61 refs., 40 figs., 16 tabs.
The problem of calculating the vibrations of rotating structures has challenged analysts since the observation that use of traditional modal coordinates in such problems leads to the prediction of instability involving infinite deformation when rotation rates exceed the first natural frequency. Much recent published work on beams has shown that such predictions are artifacts of incorporating incomplete kinematics into the analysis, but that work addresses analysis of only simple structures such as individual beams and plates. The authors present a new approach to analyzing rotating flexible structures that applies to the rotation of general linear (unjointed) structures, using a system of nonlinearly coupled deformation modes. This technique is called a Method of Quadratic Modes. 37 refs., 5 figs., 1 tab.
Results for Cr/Fe/Ni films are reported, showing that the simulation of electron scattering in solids by Monte Carlo techniques is well suited to parallel computation. Significant gains in computation time are realized and make explicit calculation of convoluted composition profiles possible. Computation time is sufficiently shortened to enable such simulations to be used in a real-time experimental environment. Because such simulations break naturally into independent computational pieces that require little intercommunication, they are ideal candidates for fast parallel implementation on a MIMD machine such as the NCUBE 2. Similar performance gains should be possible for other kinds of Monte Carlo transport simulations.
The history and current status of dish-Stirling receiver development are presented and discussed. The technical challenges to be addressed by the dish-Stirling community and the future plans at Sandia National Laboratories are outlined. Stirling tube and reflux solar receiver technologies are discussed. Pool-boiler receiver technology has been successfully tested and a number of promising heat-pipe receiver designs are very close to hardware demonstrations. The high-efficiency potential of reflux receivers has been demonstrated. However, many of the technical challenges that led to the change from tube to reflux receivers-especially life and reliability, systems integration, and hybridization-are just beginning to be addressed by the dish-Stirling community.
A procedure for updating estimates of an object's pose using information from one or more monocular images is presented. Features in monocular images are assigned correspondence with modeled three-dimensional (3-D) features based on estimated object position. An improved position estimate is computed based on the feature correspondence. The method accommodates partial occlusion or contact among objects. Features need not appear in multiple views to be used for estimation. Results from this system are presented which demonstrate the location of multiple objects within approximately 0.1 in. in translation and 2° in rotation.
A general-purpose robotic grasping system for use in unstructured environments is described. Using computer vision and a compact set of heuristics, the system automatically generates the robot arm and hand motions required for grasping an unmodeled object. The utility of such a system is most evident in environments where the robot will have to grasp and manipulate a variety of unknown objects, but where many of the manipulation tasks may be relatively simple. Examples of such domains are planetary exploration and astronaut assistance, undersea salvage and rescue, and nuclear waste site clean-up. A two-stage model of grasping is described. Stage one is an orientation of the hand and wrist and a ballistic reach toward the object; stage two is hand preshaping and adjustment. Visual features are first extracted from the unmodeled object. These features and their relations are used by an expert system to generate a set of valid reaches/grasps for the object. These grasps are then used in driving the robot hand and arm to bring the fingers into contact with the object in the desired configuration.
A method is described for obtaining the boundary equations of configuration obstacles for stick-figure manipulators in three-dimensional environments. Polyhedral obstacles are represented as a collection of planar triangular patches, and the intersection conditions between a line segment and a triangular patch are used to derive boundary equations. It is shown that the boundary equation for the nth joint variable can be solved explicitly in terms of the 0th, 1st, ..., (n-1)th joint variables. The expressions can be used to compute configuration obstacles or to analyze the geometry of contacts between manipulators and obstacles.
The experimental results of model-based and sensor-based control strategies for a two-link, flexible, planar robot arm are analyzed. Off-line optimization determines a minimum-time, straight-line tip trajectory which stays within the torque constraints of the motors and ends in a quiescent state, i.e., no vibrational transients. An efficient finite-element model is used in the optimization to approximate the flexible arm dynamics. Control schemes tested include an open-loop torque profile, a closed-loop proportional-derivative (PD) joint controller, and a feedforward controller. This last scheme uses the torque profile created from the optimization, along with PD feedback of the joint angles and proportional feedback of the strain gages, to correct for errors in the model. The results show that the best performance is achieved with this feedforward approach.
The use of one or more monocular images to estimate the three-dimensional position of objects is investigated. The identities of the objects are known, and geometric models are assumed to be available. Linear features extracted from sensor data are interpreted as corresponding with model features by search of an interpretation tree built using prior position estimates. Object positions are updated by maximum-likelihood estimation. Position estimation results from an implemented system are presented, demonstrating the location of partially occluded objects in a cluttered scene.
The geochemical modeling codes EQ3NR/EQ6 were used to model the interaction of cementitious materials with ground water from the Yucca Mountain proposed nuclear waste repository site in Nevada. This paper presents a preliminary estimate of the compositional changes caused by these interactions in the ground water and in the cement-based compounds proposed for use as sealing and shaft liner materials at the Yucca Mountain site. The geochemical speciation/solubility/reaction path codes EQ3NR/EQ6 were used to model the interaction of cementitious materials and water. Interaction of water with a cementitious material will result in dissolution of certain cement phases and changes in the water chemistry. These changes in the water chemistry may further lead to the precipitation of minerals either in the concrete or in the surrounding tuff at the Yucca Mountain Site (YMS). As part of a larger scoping study, a range of water, cement, and tuff compositions, temperatures, and reaction path modes were used. This paper presents a subset of that study by considering the interaction of three different cement formulations at 25{degree}C with J-13 water using the ``closed`` reaction path mode. This subset was chosen as a base case to answer important questions in selecting the compositions of cementitious materials for use in the proposed repository. 8 refs., 1 fig., 3 tabs.
A pilot plant project was undertaken to develop a central refrigeration compressor station capable of providing the necessary cooling to a network of nine independently-controlled environmental test chambers operating at temperatures of {minus}85{degree}F to 350{degree}F. Design features of the central two-stage (cascade) vapor compression refrigeration system are described. Computer control of the central refrigeration station is a major contribution to the improved efficiency of the overall system. A second computer-control system was developed to perform the task of environmental chamber control, test management, and chamber performance monitoring. Data on performance of the Climatic Central Refrigeration System (CCRS) are presented. 7 refs., 18 figs.
American Samoa has no indigenous fossil fuels and is almost totally dependent for energy on seaborne petroleum. However, the seven Pacific Islands located at 14 degrees south latitude that constitute American Samoa have a wide variety of renewable resources with the potential for substituting for imported oil. Included as possible renewable energy conversion technologies are solar thermal, photovoltaics, wind, geothermal, ocean thermal, and waste-to-energy recovery. This report evaluates the potential of each of these renewable energy alternatives and establishes recommended priorities for their development in American Samoa. Rough cost estimates are also included. Although renewable energy planning is highly site specific, information in this report should find some general application to other tropical insular areas.
In this report, we provide a detailed discussion of methodology of predicting cable degradation versus dose rate, temperature, and exposure time and its application to data obtained on a number of additional nuclear power plant cable insulation (a hypalon, a silicon rubber and two ethylenetetrafluoroethylenes) and jacket (a hypalon) materials. We then show that the predicted, low-dose-rate results for our materials are in excellent agreement with long-term (7 to 9 years), low dose-rate results recently obtained for the same material types actually aged under nuclear power plant conditions. Based on a combination of the modelling and long-term results, we find indications of reasonably similar degradation responses among several different commercial formulations for each of the following generic'' materials: hypalon, ethylenetetrafluoroethylene, silicone rubber and PVC. If such generic'' behavior can be further substantiated through modelling and long-term results on additional formulations, predictions of cable life for other commercial materials of the same generic types would be greatly facilitated. Finally, to aid utilities in their cable life extension decisions, we utilize our modelling results to generate lifetime prediction curves for the materials modelled to data. These curves plot expected material lifetime versus dose rate and temperature down to the levels of interest to nuclear power plant aging. 18 refs., 30 figs., 3 tabs.
PRONTO 2D and PRONTO 3D are two- and three-dimensional transient solid dynamics codes for analyzing large deformations of highly nonlinear materials subjected to high strain rates. This newsletter is issued to document changes to these codes. As of this writing, the latest version of PRONTO 2D is Version 4.5.6, and the latest version of PRONTO 3D is Version 4.5.6. This update of the two codes discusses two major modifications to the numerical formulations, three new constitutive models, and the additions and improvements of contact surfaces. Changes in file formats, other miscellaneous revisions, and the availability of PRONTO 2D and PRONTO 3D are also discussed. In addition, updated commands for PRONTO 2D are provided in Appendix A of this newsletter. 29 refs., 12 figs., 2 tabs.
This report analyzes the effects of finite-precision arithmetic on discrete Fourier transforms (DFTs) calculated using the chirp-z transform algorithm. An introduction to the chirp-z transform is given together with a description of how the chirp-z transform is implemented in hardware. Equations for the effects of chirp rate errors, starting frequency errors, and starting phase errors on the frequency spectrum of the chirp-z transform are derived. Finally, the maximum possible errors in the chirp rate, the starting frequencies, and starting phases are calculated and used to compute the worst case effects on the amplitude and phase spectrums of the chirp-z transform. 1 ref., 6 figs.
Numerous gas flow measurements have been made at the Waste Isolation Pilot Plant (WIPP) Facility horizon during 1988. All tests have been pressure decay or constant pressure tests from single boreholes drilled from the underground excavations. The test fluid has been nitrogen. The data have been interpreted as permeabilities and porosities by means of a transient numerical solution method. A closed-form steady-state approximation provides a reasonable order-of-magnitude permeability estimate. The effective resolution of the measurement system is less than 10{sup {minus}20} m{sup 2}. Results indicate that beyond 1 to 5 m from an excavation, the gas flow is very small and the corresponding permeability is below the system resolution. Within the first meter of an excavation, the interpreted permeabilities can be 5 orders of magnitude greater than the undisturbed or far-field permeability. The interpreted permeabilities in the region between the undisturbed region and the first meter from an excavation are in the range of 10{sup {minus}16} to 10{sup {minus}20} m{sup 2}. Measurable gas flow occurs to a greater depth into the roof above WIPP excavations of different sizes and ages than into the ribs and floor. The gas flows into the formation surrounding the smallest excavation tested are consistently lower than those at similar locations surrounding larger excavations of comparable age. Gas flow measured in the interbed layers near the WIPP excavations is highly variable. Generally, immediately above and below excavations, relatively large gas flow is measured in the interbed layers. These results are consistent with previous measurements and indicate a limited disturbed zone surrounding WIPP excavations. 31 refs., 99 figs., 5 tabs.
A workstation manufactured by International Business Machines Corporation (IBM) was loaned to the Simulation Technology Research Division for evaluation. We have found that these new UNIX workstations from IBM have superior cost to performance ratios compared to the CRAY supercomputers and Digital's VAX machines. Our appraisal of this workstation included floating-point performance, system and environment functionality, and cost effectiveness. Our assessment was based on a suite of radiation transport codes developed at Sandia that constitute the bulk of our division's computing workload. In this report, we also discuss our experience with features that are unique to this machine such as the AIX operating system and the XLF Fortran Compiler. The interoperability of the RS/6000 workstation with Sandia's network of CRAYs and VAXs was also assessed.
A complete external events probabilistic risk assessment has been performed for the N-Reactor power plant, making full use of all insights gained during the past ten years' developments in risk assessment methodologies. A detailed screening analysis was performed which showed that all external events had negligible contribution to core damage frequency except fires, seismic events, and external flooding. A limited scope analysis of the external flooding risk indicated that it is not a major risk contributor. Detailed analyses of the fire and seismic risks resulted in total (mean) core damage frequencies of 1.96E-5 and 4.60E-05 per reactor year, respectively. Detailed uncertainty analyses were performed for both fire and seismic risks. These results show that the core damage frequency profile for these events is comparable to that found for existing commercial power plants if proposed fixes are completed as part of the restart program. 108 refs., 85 figs., 80 tabs.
Automated entry control has become an increasingly important issue at facilities where budget constraints are limiting options for manned entry control points. Three questions are immediately raised when automated entry control is considered: What hardware is available How much does it cost How effective is it in maintaining security Ongoing work at Sandia National Labs is attempting to answer these questions and establish a data base for use by facility security managers working the problem of how to maintain security on a limited budget. 14 refs.
A wide variety of physical phenomena arising within many scientific disciplines can be described by systems of coupled partial differential equations (PDEs). The numerical approximation of these PDEs often involves the solution of a system of algebraic equations (possibly nonlinear) which are typically large, sparse and nonsymmetric. The increasing computational demands required by the solution of such complex scientific applications has motivated the current direction toward large-scale parallel computers. We, therefore, consider solution techniques of representative systems of equations on large scale MIMD machines. Our primary emphasis in this study is the evaluation of iterative methods for the solution of nonsymmetric systems. In particular, we discuss two Krylov subspace methods, the conjugate gradient squared algorithm (CGS) and the generalized minimum residual method (GMRES), along with the multigrid algorithm (MG) on massively parallel MIMD architectures. The focus of this evaluation considers the performance of various algorithm and implementation variations over a broad selection of problems using a parallel machine.
The corrosion behavior of a rapidly solidified Al-Fe-Gd alloy glass was studied in aqueous chloride environments of varying pH using potentiodynamic polarization. The corrosion behavior of a rapidly solidified pure Al glass, crystalline Al-Fe-Gd alloy and crystalline Al were measured for comparison. Due to lattice disorder, the dissolution rate of the glasses in the passive region was greater than that of their crystalline counterparts. The breakaway potentials measured for the glasses were more positive than those of the crystalline metals because film breakdown initiation sites like second phase particles and internal boundaries were not present in the glass. Alloy glass specimens exposed to alkaline solutions exhibited lower passive current densities and higher breakaway potentials than expected. This appeared to be a result of an enrichment of oxidized Fe at the specimen surface. This Fe-rich protective film also appeared to form in pits which developed on crystallized specimens tested in neutral chloride solutions.
There are tremendous resources of natural gas in tight fissured rocks, but these formations require special care for hydraulic fracturing to be successful. Serious problems include leakoff, damage and complex fracturing. Leakoff may be constant, pressure-sensitive, or accelerating. Leakoff becomes most severe when fissures begin to dilate and accept large volumes of fracture fluid, which may rapidly dehydrate a sandladen slurry. Determining values of pressure-sensitive and accelerated leakoff coefficients is difficult, and generally requires both a pressure-decline analysis (after a minifrac) and an analysis of the injection pressure. Fine-mesh sand, often used in fissured reservoirs, will help control leakoff. Damage to the natural fractures, due to leakoff of the fluid and gels and to mechanical types of damage, must be avoided, since the fissures are the production mechanism. It is particularly important to minimize the amount of liquid and gels, since the fissures are narrow and easily blocked. These concepts are also applicable to oil reservoirs.
This document contains the steady-state and loss-of-pumping accident analysis of the representative design for the Savannah River heavy water new production reactor. A description of the reactor system and computer input model, the results of the steady-state analysis, and the results of four loss-of-pumping accident calculations are presented. 5 refs., 37 figs., 4 tabs.
This report lists the measurement capabilities of the Department of Energy Contractors' Standard Laboratories within the Nuclear Weapon Complex. It is intended to foster cross-utilization of measurements between laboratories and provides a guide for survey and audit activities. Although this report was prepared by Sandia Primary Standards Laboratory (PSL), the PSL was intentionally omitted. Capabilities of the PSL are documented in SAND88-3402.UC-700.
Early attempts at estimation of stress wave damage due to blasting by use of finite element calculations met with limited success due to numerical instabilities that prevented calculations from being carried to late times. An improved damage model allows finite element calculations which remain stable at late times. Reasonable agreement between crater profiles calculated with this model using the PRONTO finite element program and excavated crater profiles from blasting experiments in granite demonstrate a successful application of this model. Detailed instructions for use of this new damage model with the PRONTO finite element programs are included. 18 refs., 16 figs.
The DEBRIS module was developed to deal with the analysis of core melt processes in Light Water Reactors (LWR's). It was designed to address the important processes associated with the late phase'' of a core meltdown. This phase encompasses the period following the loss of intact rod geometry and ending with vessel head failure. It is characterized by the melting and relocation of ceramic rich materials through a rubblized medium composed primarily of fuel pellet and oxidized cladding fragments. Of particular interest are the dynamics of the melting process, the relocation of the components, the formation of crusts, retention of molten materials by the crust, and remelting of crusts. The DEBRIS module treats these processes in a two-dimensional (r,z) geometry solving the continuity, momentum, and energy equations to describe the dynamics of meltdown. The DEBRIS models are described together with some of the analyses to which the module has been applied. In particular, a description is given of the DEBRIS module analysis of the MP-1 experiment. The DEBRIS module appears to have significant potential for the analysis of late phase'' meltdown processes and can be effectively used both in a stand-alone mode or in conjunction with the severe accident analysis codes (MELCOR,SCDAP). In addition, the module may prove effective for treatment of the early phase processes as well. 19 refs., 16 figs.
Position location is a fundamental requirement in autonomous mobile robots which record and subsequently follow x,y paths. The Dept. of Energy, Office of Safeguards and Security, Robotic Security Vehicle (RSV) program involves the development of an autonomous mobile robot for patrolling a structured exterior environment. A straight-forward method for autonomous path-following has been adopted and requires digitizing'' the desired road network by storing x,y coordinates every 2m along the roads. The position location system used to define the locations consists of a radio beacon system which triangulates position off two known transponders, and dead reckoning with compass and odometer. This paper addresses the problem of combining these two measurements to arrive at a best estimate of position. Two algorithms are proposed: the optimal'' algorithm treats the measurements as random variables and minimizes the estimate variance, while the average error'' algorithm considers the bias in dead reckoning and attempts to guarantee an average error. Data collected on the algorithms indicate that both work well in practice. 2 refs., 7 figs.
The MC4039 Unique Signal Override Plug (USOP) provides the unique signal for the B90 when fielded on aircraft that are not equipped with unique signal capability. Since the USOP is field installed, the concern is that it might be susceptible to electromagnetic radiation prior to installation on the weapon. This report documents a characterization of the USOP, evaluates various techniques for attaching electromagnetic shields, and evaluates the susceptibility of a fully assembled passive-USOP. Tests conducted evaluated the electromagnetic susceptibility of the passive, unconnected USOP. During normal operation the USOP is powered directly from the weapon. During the course of this test program two prototypes were developed. The prototype 1 USOP internal circuitry contains one SA3727 chip, five diodes, three resistors, and two capacitors; these are mounted on a circular circuit board and contained inside a metal back shell cover, which serves as an electromagnetic shield. The prototype 2 design incorporated four changes. The manufacturer of the SA3727 chip was changed from Lasarray to LSI Logic, the circuit board ground was tied to the case ground through a straight wire, Cl was changed from 1 microfarad to 0.1 microfarads. and the circuit board was changed, as required. 2 refs., 17 figs., 3 tabs. (JF)
Using Sequoyah as a representative plant, calculations have been performed with a developmental version of the CONTAIN computer code to assess the effectiveness of various possible improvements to ice condenser containments in mitigating severe accident scenarios involving direct containment heating (DCH) and/or hydrogen combustion. Mitigation strategies considered included backup power for igniters and/or air return fans, augmented igniter systems, containment venting, containment inerting, subatmospheric containment operation, reduced ice condenser bypass, and primary system depressurization. Various combinations of these improvements were also considered. Only inerting the containment or primary system depressurization combined with backup power supplies for the igniter systems resulted in large decreases in the peak pressures calculated to result from DCH events. Potential hydrogen detonation threats were also assessed; providing backup power for both the igniter systems and the air return fans would significantly reduce the potential for detonations but might not totally eliminate it. Sensitivity studies using the NUREG-1150 PRA methodology indicated that primary system depressurization combined with backup power for both igniters and fans could reduce the contribution to the mean risk potential of the class of events considered by about a factor of three. 7 refs., 6 figs., 6 tabs.
Finding new and improved means of cooling small electronic packages are of great importance to today's electronic packaging engineer. Thermal absorption through the use of a material which changes phase is an attractive alternative. Taking advantage of the heat capacity of a material's latent heat of fusion is shown to absorb heat away from the electronics, thus decreasing the overall temperature rise of the system. The energy equation is formulated in terms of enthalpy and discretized using a finite-difference method. A FORTRAN program to solve the discretized equations is presented which can be used to analyze heat conduction in a rectangular region undergoing an isothermal phase change. An analysis of heat transfer through a miniature radar electronic module cooled by a phase-change reservoir is presented, illustrating the method's advantages over conventional heat sinks. 41 refs., 11 figs., 2 tabs.
This report gives an annotated bibliography of reports published in 1989 by the Nuclear Energy Technology Directorate. A listing is also given of reports published by the staff in the nuclear energy field since 1972.
Remote automated cask handling has the potential to reduce both the occupational exposure and the time required to process a nuclear waste transport cask at a handling facility. The ongoing Advanced Handling Technologies Project (AHTP) at Sandia National Laboratories is described. AHTP was initiated to explore the use of advanced robotic systems to perform cask handling operations at handling facilities for radioactive waste, and to provide guidance to cask designers regarding the impact of robotic handling on cask design. The proof-of-concept robotic systems developed in AHTP are intended to extrapolate from currently available commercial systems to the systems that will be available by the time that a repository would be open for operation. The project investigates those cask handling operations that would be performed at a nuclear waste repository facility during cask receiving and handling. The ongoing AHTP indicates that design guidance, rather than design specification, is appropriate, since the requirements for robotic handling do not place severe restrictions on cask design but rather focus on attention to detail and design for limited dexterity. The cask system design features that facilitate robotic handling operations are discussed, and results obtained from AHTP design and operation experience are summarized. The application of these design considerations is illustrated by discussion of the robot systems and their operation on cask feature mock-ups used in the AHTP project. 11 refs., 11 figs.
This report describes the clutter model developed at Sandia National Laboratories for the SRIM code version 2.2s. The SNL clutter model is a fully polarimetric model that includes both coherent and incoherent scattering effects. The input parameters to the SNL clutter model are chosen so that an acceptable match is obtained between the model predicted data and the appropriate experimental data. These input parameters are then used in the SRIM code to simulated the desired clutter type. 12 refs., 13 figs., 2 tabs.
The DF-4 in-pile fuel damage experiment investigated the behavior of boiling water reactor (BWR) fuel canisters and control blades in the high temperature environment of an unrecovered reactor accident. This experiment, which was carried out in the Annular Core Research Reactor (ACRR) at Sandia National Laboratories, was performed under the USNRC's internationally sponsored severe fuel damage (SFD) program. The DF-4 test is described herein and results from the experiment are presented. Important findings from the DF-4 test include the low temperature melting of the stainless steel control blade caused by reaction with the B{sub 4}C, and the subsequent low temperature attack of the Zr-4 channel box by the relocating molten blade components. Hydrogen generation was found to continue throughout the experiment, diminishing slightly following the relocation of molten oxidizing zircaloy to the lower extreme of the test bundle. A large blockage which was formed from this material continued to oxidize while steam was being fed into the the test bundle. The results of this test have provided information on the initial stages of core melt progression in BWR geometry involving the heatup and cladding oxidation stages of a severe accident and terminating at the point of melting and relocation of the metallic core components. The information is useful in modeling melt progression in BWR core geometry, and provides engineering insight into the key phenomena controlling these processes. 12 refs., 12 figs.
University of Kentucky, Office of Engineering Services, (Bulletin) UKY BU
Arlowe, H.D.; Coleman, D.E.
A description is presented of MIDAS, the Mobile Intrusion Detection and Assessment System. MIDAS is a security system that can be quickly deployed to provide wide area coverage for a mobile asset. MIDAS uses two passive infrared imaging sensors, one for intruder detection and one for assessment. Detected targets are tracked while assessment cameras are directed to view the intruder location for operator observation and assessment. The dual sensor design allows simultaneous detection, assessment, and tracking. Control and status information is provided to an operator using a color graphics terminal, touch panel driven menus, and a joystick for control of the assessment sensor pan and tilt.
The Hydrologic Code Intercomparison Project (HYDROCOIN) was formed to evaluate hydrogeologic models and computer codes and their use in performance assessment for high-level radioactive-waste repositories. This report describes the results of a study for HYDROCOIN of model sensitivity for isothermal, unsaturated flow through layered, fractured tuffs. We investigated both the types of flow behavior that dominate the performance measures and the conditions and model parameters that control flow behavior. We also examined the effect of different conceptual models and modeling approaches on our understanding of system behavior. The analyses included single- and multiple-parameter variations about base cases in one-dimensional steady and transient flow and in two-dimensional steady flow. The flow behavior is complex even for the highly simplified and constrained system modeled here. The response of the performance measures is both nonlinear and nonmonotonic. System behavior is dominated by abrupt transitions from matrix to fracture flow and by lateral diversion of flow. The observed behaviors are strongly influenced by the imposed boundary conditions and model constraints. Applied flux plays a critical role in determining the flow type but interacts strongly with the composite-conductivity curves of individual hydrologic units and with the stratigraphy. One-dimensional modeling yields conservative estimates of distributions of groundwater travel time only under very limited conditions. This study demonstrates that it is wrong to equate the shortest possible water-travel path with the fastest path from the repository to the water table. 20 refs., 234 figs., 10 tabs.
The US Department of Energy is responsible for the design, construction, operation, and decommission of a site for the deep geologic disposal of high-level radioactive waste (HLW). This involves site characterization and the use of performance assessment to demonstrate compliance with regulations for HLW disposal from the US Environmental Protection Agency (EPA) and the US Nuclear Regulatory Commission. The EPA standard states that a performance assessment should consider the associated uncertainties involved in estimating cumulative release of radionuclides to the accessible environment. To date, the majority of the efforts in uncertainty analysis have been directed toward data and parameter uncertainty, whereas little effort has been made to treat model uncertainty. Model uncertainty includes conceptual model uncertainty, mathematical model uncertainty, and any uncertainties derived from implementing the mathematical model in a computer code. Currently there is no systematic approach that is designed to address the uncertainty in conceptual models. The purpose of this investigation is to take a first step at addressing conceptual model uncertainty. This will be accomplished by assessing the relative impact of alternative conceptual models on the integrated release of radionuclides to the accessible environment for an HLW repository site located in unsaturated, fractured tuff. 4 refs., 2 figs.
An intermediate step in the development of inertial confinement fusion (ICF) for power production will be the development and testing of a high-gain facility. One concept being considered for this facility is the Laboratory Microfusion Facility (LMF). Other projected applications of the LMF include high-energy-density physics experiments and nuclear effects testing. At the Air Force Institute of Technology (AFIT), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratories Albuquerque (SNLA), we have been studying the use of the LMF for nuclear effects experiments. Because of the amount of energy that will be released in a high-gain ICF test and the size of the LMF, test objects could be any size from very small electronic components to large systems; and nuclear effects in the LMF may include thermal radiation, x-rays, electromagnetic pulse, gamma rays, neutrons, or others. At AFIT, LLNL, and SNLA we have been investigating a test to expose systems to high-energy x-ray pulses, and have completed predictions of x-ray fluence, dose, etc. in various conceptual LMF reactors. However, comparison of our results is more meaningful if our prediction methods produce the same results for the same design. To establish a basis for comparison, we set up a simple benchmark problem and we each computed x-ray and neutron transport. The model and codes are described and the results are compared and discussed.
Partial least squares multivariate calibration methods were applied to the infrared spectra of a new set of borophosphosilicate glass (BPSG) thin films on silicon wafers. The calibration samples were prepared by a low pressure chemical vapor deposition (LPCVD) process. The statistically designed calibration set included data from nearly 400 coated Si wafers. Calibrations were attempted for properties such as dopant concentrations, thickness, etch rate, film stress, and electrical parameters. It was found that annealed films were predicted more precisely than unannealed films. B, P, and thickness measurements yielded the most precise results by these techniques. Multivariate calibration methods applied to etch rate for annealed films and unannealed film stress provided some limited predictive ability. The detection and removal of outliers greatly improved the analysis precisions. Finally, within wafer and between wafer dopant uniformity may be responsible for degrading the precision of these analytical methods.
The proposed high-level nuclear waste repository at Yucca Mountain, Nevada will have many miles of underground openings. Because of the long-term nature of this project it is important to gain a high level of understanding of the dynamic behavior of its underground openings. The site, located on and adjacent to the Nevada Test Site (NTS), is subject to seismic loading from both natural events and underground nuclear explosions (UNEs). While ground motions from both of these seismic sources are of interest to the Yucca Mountain Project, those resulting from earthquakes are expected to be the larger of the two and, therefore, more significant in design. It would be difficult, however, to collect underground data from earthquakes because of their unpredictable nature. In contrast, UNEs have been conducted on a regular basis at the NTS and present an opportunity to obtain data useful in understanding the seismic behavior of underground openings. To this end, the Tunnel Dynamics Experiment (TDE) was fielded adjacent to a recent UNE in a pre-existing tunnel. The objective of this experiment was to document tunnel damage corresponding to measured and observed ground motions.
This report contains the full papers submitted to the Committee on the Safety of Nuclear Installations (CSNI) Workshop on Probabilistic Safety Assessment (PSA) Applications and Limitations held in Santa Fe, New Mexico, USA, on September 4 through 6, 1990. The purpose of the Workshop was to provide an avenue for discussions in the following areas: (1) current PSA result, (2) current uses of PSA, (3) views on current limitations, (4) expert opinion, and (5) low probability numbers. The papers contained herein address these issues, along with several other related topics.
This report summarizes the advanced development of the Spectrum Sciences Model 5005-TF, Single-Event Test Fixture. The Model 5005-TF uses a Californium-252 (Cf-252) fission-fragment source to test integrated circuits and other devices for the effects of single-event phenomena. Particle identification methods commonly used in high-energy physics research and nuclear engineering have been incorporated into the Model 5005-TF for estimating the particle charge, mass, and energy parameters. All single-event phenomena observed in a device under test (DUT) are correlated with an identified fission fragment, and its linear energy transfer (LET) and range in the semiconductor material of the DUT.
This report describes the features and use of the Sandia National Laboratories Assembly Test Chip Ver. 01 (ATC01). This chip contains a variety of Al conductor features which are intended for use in corrosion testing. These include triple tracks with a variety of line and gap widths, ladder structures, straight line structures, and van der Pauw sheet resistance structures. The chip is square, approximately 0.250 in. on a side, with a minimum Al feature size of 1.25 {mu}m. The various test structures on the die are described in detail and bonding layout data are given. Finally, we give an example of measurements made on ATC01 when packaged in a 40 lead CERDIP. 15 refs., 7 figs., 7 tabs.
Sub-gridding techniques enable finite-difference time-domain (FDTD) electromagnetic codes to model apertures that are much narrower than the spatial resolution of the FDTD mesh. Previous thin-slot methods have assumed that the slot walls are perfectly conducting. As the slot depth-to-width ratio becomes large, interior wall losses for realistic materials can significantly affect the coupling through the slot, and therefore these loss effects should not be neglected. This paper presents two methods for incorporating loss for walls with good, but not perfect conductivity, into the FDTD calculations. The first method modifies an FDTD equation internal to the slot to include a surface-impedance contribution. This method is appropriate for the usual FDTD thin-slot formalisms. The second method includes the losses into a half-space'' integral equation that can be used by the recently introduced Hybrid Thin-Slot Algorithm. Results based on the two methods are compared for a variety of slot parameters and wall conductivities.
The establishment of a database for the materials that are used in production Li(Si)/FeS{sub 2} thermal batteries designed at Sandia National Laboratories is described. The database is a Hewlett-Packard (HP) network type (IMAGE) designed to run on an HP3000 computer. Heavy emphasis is placed on the use of screen forms for entry, editing, and retrieval of data. Custom screen forms were used for the various materials in the battery. For the purposes of the materials database, each battery is composed of four mixes: cathode, separator, anode, and heat (pyrotechnic) powders. A consistent lot-numbering system was adopted for both the mixes and the discrete components that make up the mixes. Each serial number of a particular battery is linked to the lot numbers of the four mixes used in the battery. Each mix, in turn, is linked to the lot numbers of the discrete components that are contained within the mix. This allows traceability of each of the components used in any given serial number of a particular battery. The materials database provides the necessary traceability, as required by the Department of Energy, for the lifetime of the program associated with the battery. 3 refs., 23 figs.
A method which is capable of efficient calculation of the axisymmetric flow field produced by a large system of ring vortices is presented in this report. The system of ring vortices can, in turn, be used to model body surfaces and wakes in incompressible unsteady axisymmetric flow fields. This method takes advantage of source point and field point series expansions which enables one to make calculations for interactions between groups of vortices which are in well separated spatial domains rather than having to consider interactions between every pair of vortices. In this work, series expansions for the stream function of the ring vortex system are obtained. Such expansions explicitly contain the radial and axial velocity components. A Fortran computer code RSOLV has been written to execute the fast solution technique to calculate the stream function and the axial and radial velocity components at points in the flow field. Test cases have been run to optimize the code and to benchmark the truncation errors and CPU time savings associated with the method. Non-dimensional truncation errors for the stream function and total velocity field are on the order of 5 {times} 10{sup {minus}5} and 3 {times} 10{sup {minus}3} respectively. Single precision accuracy produces errors in these quantities up to about 1 {times} 10{sup {minus}5}. For 100 vortices in the field, there is virtually no CPU time savings with the fast solver. For 10,000 vortices in the flow, the fast solver obtains solutions in about 1% to 3% of the time required for the direct solution technique. Simulations of vortices with square and circular cores were run in order to obtain expressions for the self-induced velocities of such vortices. 8 refs., 26 figs.
A balloon-borne integrating nephelometer has been successfully developed and flown by Sandia National Laboratories and Radiance Research. This report details instrument design, calibration and data conversion procedure. Free and tethered balloon transport and telemetry systems are described. Data taken during March 1989 South-Central New Mexico free flight ascents are presented as vertical profiles of atmospheric particle scattering coefficient, temperature and balloon heading. Data taken during December 1989 Albuquerque, New Mexico tethered flights are also presented as vertical profiles. Data analysis shows superior instrument performance. 5 refs., 22 figs.
This report describes the computer program used at the Tonopah Test Range to maintain the explosive inventory. The program, which uses dBASE III or dBASE III Plus and runs on an IBM PC or compatible, has the capabilities to update (add or subtract) items, edit or delete, append, and generate various reports.
Mass measurements may be greatly enhanced by an understanding of the operation of balances, the effects of buoyancy, practices encountered in weighing and the impacts and meanings of revelant mass standards. Beginning with the basic forces acting on weights, the equations brought to equality in balances are developed. These give explanation of the weighing process and an appreciation for some balance characteristics. The requirements of relevant mass standards are also reviewed. Recommendations are made for operation of practical mass calibration. An appendix is attached which gives computation examples using apparent mass'' and also gives a method for determining the density of mass artifacts or unknown materials. 2 tabs.
This project is a collaboration between Sandia National Laboratories and Harvey E. Yates Company being conducted under the auspices of the Oil Recovery Technology Partnership. The project seeks to apply perspectives related to the effects of natural fractures, stress, and sedimentology to the simulation and production of low-permeability gas reservoirs to low-permeability oil reservoirs as typified by the Bone Spring sandstones of the Permian Basin, southeast New Mexico. This report presents the results and analysis obtained in 1989 from 233 ft of oriented core, comprehensive suite of logs, various in situ stress measurements, and detailed well tests conducted in conjunction with the drilling of two development wells. Natural fractures were observed in core and logs in the interbed carbonates, but there was no direct evidence of fractures in the sandstones. However, production tests of the sandstones indicated permeabilities and behavior typical of a dual porosity reservoir. A general northeast trend for the maximum principal horizontal stress was observed in an elastic strain recovery measurements and in strikes of drilling-induced fractures; this direction is subparallel to the principal fracture trend observed in the interbed carbonates. Many of the results presented are believed to be new information for the Bone Spring sandstones. 57 figs., 18 tabs.
This report addresses the need for commercially available lighting design computer programs and evaluates several of these programs. Sandia National Laboratories uses these programs to provide lighting designs for exterior closed-circuit television camera intrusion detection assessment for high-security perimeters.
This report summarizes the role of performance assessment in assessing compliance with the containment requirements in 40 CFR Part 191, the Environmental Protection Agency's Standard for the disposal of spent nuclear fuel, high-level and transuranic radioactive wastes. In 1986, Hunter et al. prepared a similar report (NUREG/CR-4510, SAND86-0121) which provided an overview of the approach to assess compliance with this standard. The present report builds on its predecessor in that it incorporates advances in performance assessment subsequent to Hunter et al.'s report. The main purpose of this report is to serve as a mechanism for transferring to the Nuclear Regulatory Commission (NRC) and its contractors the performance assessment methodologies (PAMs) developed by Sandia National Laboratories (SNL) for high-level radioactive waste repositories. The report starts with a discussion of the requirements in 40 CFR Part 191 and focuses on the containment requirements (Section 191.13). It follows with a discussion of the role of performance assessment and its use in regulatory compliance. The report concludes with a discussion of sources of uncertainty, treatment of uncertainties, and the construction of the complementary cumulative distribution function of summed normalized total releases to the accessible environment for one or more scenarios. Examples are presented of the demonstration of performance assessment methodologies for high-level waste disposal at two hypothetical sites. Consistent with the technology transfer objective, numerous references are made throughout this report to publications related to the SNL PAMs. As such, this is not a stand-alone report and the reader is encouraged to consult those references. 30 refs., 9 figs., 1 tab.
NIRVANA is an effort to standardize electrical computer-aided design workstations at Sandia National Laboratories in Albuquerque, New Mexico. The early effect of this project will be the introduction of at least 60 new engineering workstations at Sandia National Laboratories, Albuquerque, and at Allied Signal, Kansas City Division. These workstations are expected to begin arriving in September 1990. This paper outlines the requirements that a NIRVANA Network must satisfy to comply with the Government Open Systems Interconnect Profile (GOSIP). The author also identifies several issues involved in achieving GOSIP compliance. 4 refs., 1 fig.
Response to interrupts within a certain time frame is an important issue for all software operating in real-time environment. A knowledge-based system (KBS) is no exception. Prior work on real-time knowledge-based systems either concentrated on improving the performance of the KBS in order to meet these constraints or focused on producing a better solution as more time was allowed. However, a problem with much of the latter research was that it required inference-time costs to be hardcoded into the different branches of reasoning. This limited the type of reasoning possible and the size of the KBS. Furthermore, performing the analysis required to derive those numbers is very difficult in knowledge based systems. This research explored a model for overcoming these drawbacks. It is based on integrating conventional programming techniques used to control task processing with knowledge-based techniques used to actually produce task results. The C-Language Integrated Production System (CLIPS) was used for the inference engine in the KBS; using CLIPS for the inference engine simplified the rapid context switching required. Thus, the KBS could respond in a timely manner while maintaining the fullest spectrum of KBS functionality.
Welcome to this first issue of Manufacturing Technology, one of three new technology bulletins published at Sandia National Laboratories in which we seek to share information with US industry about applications of technology. Inside this issue: industry/DOE/Sandia agreement to strengthen specialty metals competitiveness; silicon micromachining produces microscopic parts; Sandia develops state-of-the-art capacitor winding machine; new robotic system spells finis to manual edge finishing; and milling assistant speeds numerically controlled machine programming.
This paper discusses several methods to detect the presence of and track the frequency of a chirping signal in broadband noise. The dynamic behavior of each of the methods is described and tracking error bounds are investigated in terms of the chirp rate. Frequency tracking and behavior in the presence of varying levels of noise are illustrated in examples. 11 refs., 29 figs.
The authors have developed and applied a methodology to evaluate and prioritize proposed waste minimization activities affecting Department of Energy (DOE) programs. The approach provides a systematic and defensible method for selecting a set of waste minimization proposals that maximizes the benefits to DOE while maintaining costs within a specified budget. The report discusses the development of a structured set of evaluation criteria to characterize waste minimization issues; techniques for documenting the anticipated and potential costs, risks, and benefits of waste minimization proposals; and a method of translating disparate data into a figure of merit for each proposal. A test case demonstration of this prioritization approach was applied to proposals currently being considered at two DOE weapons production facilities. Recommendations are provided for combining this approach with the existing DOE proposal selection process. 9 refs., 9 figs., 3 tabs.
NIRVANA is an effort to standardize electrical computer-aided design workstations at Sandia National Laboratories in Albuquerque, New Mexico. The early effect of this project will be the introduction of at least 60 new engineering workstations at Sandia National Laboratories. Albuquerque, and at Allied Signal, Kansas City Division. These workstations are expected to begin arriving in September 1990. This paper proposes a design and outlines the requirements for a network to support the NIRVANA project. The author proposes a near-term network design, describes the security profile and caveats of this design, and proposes a long-term networking strategy for NIRVANA. 6 refs., 7 figs.
This WIPP Bin-Scale CH TRU Waste Test program described herein will provide relevant composition and kinetic rate data on gas generation and consumption resulting from TRU waste degradation, as impacted by synergistic interactions due to multiple degradation modes, waste form preparation, long-term repository environmental effects, engineered barrier materials, and, possibly, engineered modifications to be developed. Similar data on waste-brine leachate compositions and potentially hazardous volatile organic compounds released by the wastes will also be provided. The quantitative data output from these tests and associated technical expertise are required by the WIPP Performance Assessment (PA) program studies, and for the scientific benefit of the overall WIPP project. This Test Plan describes the necessary scientific and technical aspects, justifications, and rational for successfully initiating and conducting the WIPP Bin-Scale CH TRU Waste Test program. This Test Plan is the controlling scientific design definition and overall requirements document for this WIPP in situ test, as defined by Sandia National Laboratories (SNL), scientific advisor to the US Department of Energy, WIPP Project Office (DOE/WPO). 55 refs., 16 figs., 19 tabs.
Calculations have been performed with the HULL hydrocode to study ground shock effects for multiple earth penetrator weapon (EPW) bursts in hexagonal-close-packed (HCP) arrays. Several different calculational approaches were used to treat this problem. The first simulations involved two-dimensional (2D) calculations, where the hexagonal cross-section of a unit-cell in an effectively-infinite HCP array was approximated by an inscribed cylinder. Those calculations showed substantial ground shock enhancement below the center of the array. To refine the analysis, 3D unit-cell calculations were done where the actual hexagonal cross-section of the HCP array was modelled. Results of those calculations also suggested that the multiburst array would enhance ground shock effects over those for a single burst of comparable yield. Finally, 3D calculations were run in which an HCP array of seven bursts was modelled explicitly. In addition, the effects of non-simultaneity were investigated. Results of the seven-burst HCP array calculations were consistent with the unit-cell results and, in addition, provided information on the 3D lethal contour produced by such an array.
Analyses of the internal argon gas concentrations monitored on surveillance units of the W84 indicates that field aging of this weapon for times up to {approximately}4 years does not lead to important increases in the rate at which water leaks into the interior of the weapon. This implies that the EPDM environmental seals used on the W84 do not age significantly over this time period. By comparing the percentages of oxygen and argon in the internal atmosphere, an estimate of the oxygen consumption rate is made for a typical W84 unit. The argon gas analysis approach is then applied to the W88, which is sealed with a new EPDM material. Predictive expressions are derived which relate the anticipated argon gas concentrations of future, field-returned units to their water leakage rates. The predictions are summarized in convenient plots, which can be immediately and easily applied to surveillance data as reported. Since the argon approach is sensitive enough to be useful over the entire lifetime of the W88, it can be used to point out leaking units and to determine whether long-term aging has any significant effect on the new EPDM material. 11 refs., 10 figs., 3 tabs.
The Robotic Edge Finishing Laboratory at Sandia National Laboratories is developing four areas of technology required for automated deburring, chamfering, and blending of machined edges: (1) the automatic programming of robot trajectories and deburring processes using information derived from a CAD database, (2) the use of machine vision for locating the workpiece coupled with force control to ensure proper tool contact, (3) robotic deburring, blending, and machining of precision chamfered edges, and (4) in-process automated inspection of the formed edge. The Laboratory, its components, integration, and results from edge finishing experiments to date are described here. Also included is a discussion of the issues regarding implementation of the technology in a production environment. 24 refs., 17 figs.
A series of impact experiments on a composite propellant, an energetic propellant, and their simulants was recently completed using a light-gas gun. Previous experiments were done to obtain Hugoniot data, to investigate the pressure threshold at which a reaction occurs, and to measure spall damage at various impact velocities. The present studies measured the attenuation of shock waves in these materials, completing the shock characterization needed for material modeling. An initial impulse of 2.0 GPa magnitude and {approximately}0.6 {mu}s duration was imposed upon samples of various thicknesses. VISAR was used to measure the free-surface velocity at the back of the samples; these data were used to generate a curve of shock-wave attenuation versus sample thickness for each material. Results showed that all four materials attenuated the shock wave very similarly. Material thicknesses of 3.0, 7.62, 12.7, and 19.0 mm attenuated the shock wave {approximately}16%, 33%, 50%, and 66% respectively. 14 refs., 12 figs., 4 tabs.
This report concerns the evaluation of the Stellar Systems Inc. E-Field intrusion detection system Series 800 control unit and the 5000 Series hardware components. Included are functional descriptions, installation procedures, testing procedures, and testing/operational results. 35 figs.
The WhiteStar project provides design engineers with needed part design data. WhiteStar encourages the use of preferred parts by providing a user-convenient parts database. This report shows selections the user makes in order to obtain information on a particular part. 15 figs.
This report investigates the behavior of a family of finite element error estimators based on projected stresses, i.e., continuous stresses that are a least squared error fit to the conventional Gauss point stresses. An error estimate based on element force equilibrium appears to be quite effective. Examples of adaptive mesh refinement for a one-dimensional problem are presented. Plans for two-dimensional adaptivity are discussed. 12 refs., 82 figs.
This report describes the design intent, design considerations, system use, development, product characteristics, and early production history of the MC3714 Thermal Battery. This battery has a required operating life of 146 s above 24.0 V with a constant current load of 0.5 A. It is activated when the MC3830 Actuator initiates the WW42C1 Percussion Primer in the battery. The MC3714 employs the Li(Si)/LiCl-CCl/lithiated FeS{sub 2} electrochemical system. The battery is a hermetically sealed right-circular cylinder with an antirotation ring brazed to the base of the cylinder. The battery is 50 mm long and 38.1 mm in diameter. The mass of the battery is 165 g. The battery was designed and developed to provide the power for the W82 JTA Telemetry System. 8 refs., 12 figs., 11 tabs.
Infrared video thermograms of a portion of the surface of graphite limiters in Textor were taken during several disruptions. Estimates of the deposition power density were made by comparison of the observed temperature histories with those calculated from a numerical thermal conduction model. It was found that the heat flux, at the observed locations, often occurred in sharp submillisecond bursts, the magnitudes of which were much larger than the heat flux density averaged over the whole disruption. 5 refs., 4 figs.
The mechanical properties of a coring from the bottom of the MOSAIK KfK cask were determined as a function of through wall position for the 21 cm thick section. The elastic moduli were determined from ultrasonic velocity measurements. The standard tensile properties were determined as a function of strain rate at {minus}29{degree}C. The Charpy impact behavior was measured as a function of temperature from {minus}100 to {plus}100{degree}C. The fracture toughness was determined for both static and elevated loading rates (at {minus}29{degree}C). In addition to these mechanical properties, the variation in microstructure and composition with position in the coring is reported. The mechanical properties provide the essential information for the stress analysis modeling of the behavior of the cask during a drop test which will be conducted to simulate a very severe accident condition. The results from the elevated loading rate fracture toughness tests are used to suggest the severity of the flaws that should be introduced into the cask for the sequential series of drops which are scheduled to begin in March 1990. 24 refs., 16 figs., 6 tabs.
Recently an appreciable number of continuous release profiles have been measured from dynamic experiments with geological materials. For each material an empirical generalization of the available release curves may be constructed to allow easy application of the experimental data to problems in much the same way as a linear shock velocity -- particle velocity fit allows easy application of Hugoniot data. This generalization is made in two steps. The first is to compute the Eulerian axial modulus at the Hugoniot pressure and its first three pressure derivatives along the release for each test. This corresponds to a partial Taylor series of the axial modulus, which integrates to give a very close match to the original release. An alternative formulation, which takes volume as the independent variable, fails because that Taylor series does not converge with the rapidity needed for these calculations. The second step is to plot each of these quantities against the Hugoniot pressure for the suite of tests, and fit these data. A release from an arbitrary pressure within the general range of the experimental data may be computed by using the interpolated modulus and its interpolated derivatives. This generalization, which allows volume to be computed as a function of pressure, reproduces the experimental curves fairly well. We present the results of applying this technique to release data for Mini Jade 2 grout, and briefly compare these results with those from several Nevada Test Site tuffs, saturated and dry Indiana Limestone, and aluminum. Finally, we use the generalized Mini Jade 2 data to solve a sample problem, that of estimating the error produced by making the release = Hugoniot'' assumption in the analysis of ground motion gauges in an underground test. 12 refs., 14 figs., 5 tabs.
Exposure of polymers to air during aging (radiation, thermal, UV) often results in inhomogeneously oxidized samples, a complication which impacts attempts both to understand the oxidation process and to extrapolate accelerated exposures to long-term conditions. The most important such complication involves diffusion-limited oxidation which can occur if the rate of oxygen consumption in a material is greater than the rate at which oxygen can be resupplied by diffusion processes from the surrounding air atmosphere. Thus, in order to confidently extrapolate accelerated simulations to long-term, air-aging conditions, one must be able to monitor and quantitatively understand diffusion-limited oxidation effects. Experimental techniques for monitoring diffusion-limited oxidation profiles have recently been reviewed. By comparing experimental profiles with theoretically derived profiles, the theories can be verified and then confidently used to predict the importance of diffusion effects prior to the initiation of aging tests. This paper summarizes what we believe is the first quantitative experimental confirmation of diffusion-limited oxidation theories.
The tests described in this report were conducted to obtain information on the effects target characteristics have on portal type metal detector response. A second purpose of the tests was to determine the effect of detector type and settings on the detection of the targets. Although in some cases comparison performance of different types and makes of metal detectors is found herein, that is not the primary purpose of the report. Further, because of the many variables that affect metal detector performance, the information presented can be used only in a general way. The results of these tests can show general trends in metal detection, but do little for making accurate predictions as to metal detector response to a target with a complex shape such as a handgun. The shape of an object and its specific metal content (both type and treatment) can have a significant influence on detection. Thus it should not be surprising that levels of detection for a small 100g stainless steel handgun are considerably different than for detection of the 100g stainless steel right circular cylinder that was used in these tests. 7 figs., 1 tab.
A steam blowdown test was performed at the Surtsey Direct Heating Test Facility to test the steam supply system and burst diaphragm arrangement that will be used in subsequent Surtsey Direct Containment Heating (DCH) experiments. Following successful completion of the steam blowdown test, the HIPS-10S (High-Pressure Melt Streaming) experiment was conducted to demonstrate that the technology to perform steam-driven, high-pressure melt ejection (HPME) experiments has been successfully developed. In addition, the HIPS-10S experiment was used to assess techniques and instrumentation design to create the proper timing of events in HPME experiments. This document discusses the results of this test.
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High pressure Hugoniot and release equation of state data are provided for samples from three Nevada Test Site rock units. These are the MC-2 and MC-3 members of the P-Tunnel (Paintbrush) Tuff and the N-Tunnel (Tunnel Bed) Tuff. The technique used provides continuous release trajectories from the Hugoniot pressure down to approximately half of the Hugoniot pressure. Hugoniot and release results for the MC-2 and MC-3 members are very similar, while the Hugoniot of the N-Tunnel Tuff is somewhat stiffer, consistent with the higher density of this tuff as tested. The materials were tested at less than full saturation; correcting for this tends to narrow the difference in the properties of the two rock types sufficiently that the data do not provide a basis for predicting significantly different groundshock properties of the three units, leaving unexplained the anomalously high groundshock attenuation observed in the Mission Cyber event (performed in the MC-2 unit of the Paintbrush tuff). 26 refs., 61 figs., 9 tabs.
During rapid solidification, nonequilibrium interface kinetics alter the predictions of the Mullins-Sekerka theory for the stability of a planar interface against cellular breakdown. The velocity-dependence of the partition coefficient and of the Sn concentration at the onset of cellular breakdown have been measured during pulsed laser melting of Si--Sn alloys. The Mullins-Sekerka theory is modified by inserting a velocity-dependent partition coefficient and a velocity-dependent slope of the kinetic liquids,'' both of which are extracted from the Continuous Growth Model for interface kinetics. These nonequilibrium interface kinetic effects increase the predicted critical concentration for cellular breakdown by two orders of magnitude for Sn in Si, and account fairly well for the experimental results. 34 refs., 3 figs.
Several models of runaway electron generation during a disruption are described and applied to the problem of determining the radiation loss and energy limit of runaway electrons. In particular the prediction of orbits and energy limits for proposed ITER design are discussed. It was found that resonance between the electron gyrofrequency and the fundamental ripple frequency can lead to large synchrotron radiation losses and create an upper bound on runaway energy. Interactions with the second harmonic of the ripple field are very sensitive to ripple amplitude and may lead to a further reduction in runaway energy. In ITER this effect can limit the runaway energy to values of 270 MeV. A lump circuit model of the plasma can be used to determine the coupled interactions of the runaway currents with the plasma and control circuit currents. Depending on what is assumed about the perpendicular energy of the runaway electrons. Maximum values of runaway energy predicted for ITER are in the range of 35 to 120 MeV. 4 refs., 15 figs.
A bilateral teleoperation system consists of a local master manipulator and a remotely located slave manuipulator. Generalized velocity commands are sent forward from the master to the slave, and generalized force/torque information is reflected'' back from the slave to the master. Often there is a transmission delay incurred when communicating between the two subsystems which causes instability in the bilateral teleoperator. Recently, a solution for this instability problem was found, based on mimicking the behavior of a lossless transmission line. Although this solution provides steady-state force and velocity tracking, it does not provide steady-state force and position tracking, as is desired for bilateral teleoperation. In this paper a modification is given to the basic control law which overcomes this difficulty. 13 refs., 6 figs., 1 tab.
This document serves as the proceedings for the annual project review meeting held by Sandia's Photovoltaic Cell Research Division and Photovoltaic Technology Division. It contains information supplied by each organization making a presentation at the meeting, which was held August 7 through 9, 1990 at the Sheraton Hotel in Albuquerque, New Mexico. Sessions were held to discuss national photovoltaic programs, one-sun crystalline silicon cell research, concentrator silicon cell research, concentrator 3-5 cell research, and concentrating collector development.
The Center for Compound Semiconductor-Technology (CCST)at Sandia National Laboratories encompasses the full range of required activities--theoretical and experimental solid-state physics, materials science, crystal growth, device design, and fabrication--to develop the next generation of electronic and optoelectronic devices. Semiconductor electronics are vital to the communications and computer industries and to the nation's defense. Compound semiconductors offer very high-speed electronics and integrated optical and electronic capabilities not available with silicon, and will underlie future electronic, optoelectronic, and photonic technologies. The purpose of the CCST is to perform collaborative research generic to electronic and optoelectronic technologies in compound semiconductors. The CCST also includes related research in high-temperature superconducting electronics and hybrid superconductor-semiconductor devices. Facilities in the CCST include extensive molecular-beam epitaxy and metal-organic chemical vapor deposition crystal growth capabilities, a 400-keV ion implanter, and a new 3700 net square foot, class 1000/100 clean room with state-of-the-art processing equipment. Addition of an electron-beam lithography system to permit fabrication of devices with feature sizes below 100 nm is planned for the near future.
The near-field, explosive dispersal of a liquid into air has been explored using a combination of analytical and numerical models. The near-field flow regime is transient, existing only as long as the explosive forces produced by the detonation of the burster charge dominate or are approximately equal in magnitude to the aerodynamic drag forces on the liquid. The near-field model provides reasonable initial conditions for the far-field model, which is described in a separate report. The near-field model consists of the CTH hydrodynamics code and a film instability model. In particular, the CTH hydrodynamics code is used to provide initial temperature, pressure, and velocity fields, and bulk material distribution for the far-field model. The film instability model is a linear stability model for a radially expanding fluid film, and is used to provide a lower bound on the breakup time and an upper and lower bound on the initial average drop diameter for the liquid following breakup. Predictions of the liquid breakup time and the initial arithmetic average drop diameter from the model compare favorably with the sparse experimental data. 26 refs., 20 figs., 8 tabs.
This report highlights Sandia National Laboratories' work in the following areas: photometrics and optical development; still and time-lapse photography; real-time motion photography; high-speed photography; image-motion photography; schlieren photography; ultra-high-speed photography; electronic imaging; shuttered video and high-speed video; infrared imaging radiometry; exoatmospheric photography and videography; microdensitometry and image analysis; and optical system design and development.
This report describes reference concepts for a hydrogen-oxygen combustion, turboalternator power system that supplies power during battle engagement to a space-based, ballistic missile defense platform. All of the concepts are open''; that is, they exhaust hydrogen or a mixture of hydrogen and water vapor into space. We considered the situation where hydrogen is presumed to be free to the power system because it is also needed to cool the platform's weapon and the situation where hydrogen is not free and its mass must be added to that of the power system. We also considered the situation where water vapor is an acceptable exhaust and the situation where it is not. The combination of these two sets of situations required four different power generation systems, and this report describes each, suggests parameter values, and estimates masses for each of the four. These reference concepts are expected to serve as a baseline'' to which other types of power systems can be compared, and they are expected to help guide technology development efforts in that they suggest parameter value ranges that will lead to optimum system designs. 7 refs., 18 figs., 5 tabs.
This report covers the development of improved assembly processes for the Quartz Digital Accelerometer cantilever. In this report we discuss improved single-assembly tooling, the development of tooling and processes for precision application of polyimide adhesive, the development of the wafer scale assembly procedure, and the application of eutectic bonding to cantilever assembly. 2 refs., 17 figs.
A computer code, PREGO, has been developed to perform calculations for three related problems: reflection of an acoustic wave against a layered viscoelastic medium: (water/medium); transmission of an acoustic wave through such a medium (water/medium/water); and radiation of an acoustic wave through such a medium: (medium/water). This code draws an experience gained in writing and using a predecessor code, IMPEDE, which was devised to calculate the steady state reflection of an acoustic wave impinging on a layered substrate of elastic or viscoelastic materials. That code employed a finite element formulation to discretize the complex-valued, second order ordinary differential equations for monochromatic steady state acoustics. The principles of numerical analysis that underlie PREGO are different and less subject to discretization error than those used in IMPEDE. The formulation used in PREGO is similar to that of higher dimensional boundary integral formulations in that it uses closed form expressions for the complex velocity fields in each layer, given in terms of the velocities at the boundary of that layer. The solutions for each layer are coupled together by requiring that stresses and velocities be continuous across interfaces. 5 refs., 4 figs.
A performance assessment methodology has been developed for use by the US Nuclear Regulatory Commission in evaluating license applications for low-level waste disposal facilities. This report provides a summary of background reports on the development of the methodology and an overview of the models and codes selected for the methodology. The overview includes discussions of the philosophy and structure of the methodology and a sequential procedure for applying the methodology. Discussions are provided of models and associated assumptions that are appropriate for each phase of the methodology, the goals of each phase, data required to implement the models, significant sources of uncertainty associated with each phase, and the computer codes used to implement the appropriate models. In addition, a sample demonstration of the methodology is presented for a simple conceptual model. 64 refs., 12 figs., 15 tabs.
Glass-to-metal seals are an integral part of many electronic components. When seals are formed at elevated temperatures and cooled to room temperature, residual stresses are generated by the unequal thermal contractions of the constituent materials. The combination of high stress and low fracture resistance of glass makes it extremely difficult to design and build hermetic glass-to-metal seals. Rigorous and robust stress analyses must incorporate the complex and coupled changes in volumetric strain and stress relaxation which occur as glass passes through the liquid/solid temperature regime. The phenomenological behavior of glass can be modeled viscoelastically. The theory and numerical discretization of the viscoelastic equations is presented for use in finite element programs. Vectorizable integration schemes are derived for both the traditional hereditary integrals of viscoelasticity and the equivalent rate forms of the equations. The general behavior of glass is discussed and related to the viscoelastic model. Solutions to discretized viscoelastic equations are applied to an example problem and compared to results obtained from experimental data. The viscoelastic model of glass provides a new capability to analyze and design actual manufacturing processes by predicting, a priori, the effects of temperature history on the residual stress state.
Kerberos is a network user authentication system that was recently developed at the Massachusetts Institute of Technology (MIT). It has been adopted by Sandia National Laboratories, Albuquerque, for use in the Secure Supercomputing Network (SSN) which is currently under development. FTP and TELNET are two of the most important network applications for the SSN, which is to use the TCP/IP protocol suite. FTP provides capabilities for bulk file transfer between nodes and TELNET provides a remote interactive login capability across the network. This design describes how authentication is currently performed in FTP and TELNET using clear text passwords and proposes a method for modifying them to use Kerberos authentication.
When the boundary integral equation method is applied to exterior acoustics problems, singularities occur in the resulting algebraic equations at various frequencies associated with the eigenvalues of an interior problem. These frequencies are referred to as forbidden,'' and various methods have been devised to overcome the computational difficulties presented at these frequencies. The work presented here is an extension to the CHIEF method in that higher derivatives, in addition to the function itself, are constrained to be zero at selected points in the interior domain. Whereas the relative success of either method depends on the quantity and selection of interior points, the SuperCHIEF method requires fewer interior points and is less sensitive to point selection, resulting in improved robustness without significant increase in computational complexity. 3 refs., 14 refs.
Massively parallel computers and computer networks are beginning to appear as an integral part of the scientific computing workplace. This report documents the goals and the corresponding development plan of the massively parallel project of Departments 1530 and 1420. The main goal of the project is to provide a clear understanding of the issues and difficulties involved in bringing the current production hydrocode CTH to the state of being portable to a number of currently available parallel computing architectures. In the process of this research, various working versions of the code will be produced. 6 refs., 6 figs.
This report examines effects of aging on cables, connections, and containment electrical penetration assemblies (EPAs). Aging is defined as the cumulative effects that occur to a component with the passage of time. If unchecked, these effects can lead to a loss of function and a potential impairment of plant safety. This study includes a review of component usage in nuclear power plants; a review of some commonly used components and their materials of construction; a review of the stressors that the components might be exposed to in both normal and accident environments; a compilation and evaluation of industry failure data; a discussion of component failure modes and causes; and a brief description of current industry testing and maintenance practices. 51 refs., 12 figs., 12 tabs.
CEPXS/ONELD is a discrete ordinates code package for one-dimensional coupled electron-photon transport over the energy range of 100 MeV to 1.0 keV. In this Results Guide, CEPXS/ONELD predictions are compared to the predictions of Monte Carlo codes and to experiment. These comparisons are made for a variety of quantities, including energy deposition, charge deposition and electron current spatial profiles as well as electron and photon spectra. Sensitivity studies are presented that show how the numerical approximations of CEPXS/ONELD can affect the accuracy of predictions. Guidelines for the efficient and accurate use of the code package are given. All examples involve one-dimensional planar geometry and non-adjoint transport. 35 refs.
Charge exchange results in the transfer of momentum from an ion to a neutral atom, thus it is equivalent to a slowing down mechanism for ions. This might be helpful in IFR propagation of relativistic electron beams. The effect of charge exchange on the ion hose instability and channel expansion after beam passage is investigated in this report. For parameters of interest to current experiments, it is found that the effect on growth of the ion hose instability is insignificant, but there is significant reduction in the energy of the expanding ions after passage of the electron beam. 5 refs., 5 figs.
The nickel/hydrogen battery was developed in the 1970s as an energy storage subsystem for commercial communication satellites. The advantages offered by nickel/hydrogen batteries, including long life, low maintenance and high reliability, make it very attractive for terrestrial applications such as stand-alone photovoltaic systems. The major drawback to the wider use of the nickel/hydrogen battery is its high initial cost. Sandia National Laboratories has directed cost-shared contracts at Comsat Laboratories and Johnson Controls, Inc. to reduce the cost, and a battery consisting of prismatic cells in a common pressure vessel has evolved. Contract deliverables include cells and batteries that are evaluated at Sandia. This report summarizes the results over the past two years of both cycle and solar testing. 6 refs., 12 figs., 5 tabs.
This report will present the development history, characterization data and the qualification activities for the SA3646. This device is manufactured by SEEQ Technology Inc., with part number LM28C256-250/B and is a 256K Electricity Erasable Programmable Read Only Memory (EEPROM). 14 refs., 25 figs.
This report documents the development and testing of the 375492, a Schottky barrier diode die, similar to the Hewlett-Packard 5082-0094. 18 figs., 4 tabs.
Eaton, D.S.; Hall, R.C.; Orman, J.L.; Klamerus, J.
This document contains the technical specifications and implementation details for the Product Evaluation Management Information System (PREMIS) Version 1.1.2. This document does not include the requirements analysis or design information and is not intended as a user's guide. The INGRES Applications-by-Forms (ABF) software development tool was used to specify and define the modules and screens which comprise the PREMIS application. Several external procedures are called by the ABF procedures; these have been written in VAX/VMS DCL (Digital Command Language) and SQL (Standard Query Language). These specifications together with the PREMIS information model and corresponding database definition constitute the PREMIS Version 1.1.2 technical specification and implementation description presented herein.
The feasibility of performing, numerous spent fuel cask operations using fully integrated robotic systems is under evaluation. Using existing technology, operational and descriptive software and hardware in the form of robotic end effectors are being designed in conjunction with interfacing cask components. A robotic radiation and contamination survey system has been developed and used on mock-up cask hardware to evaluate the impact of such fully automated operations on cask design features and productivity. Based on experience gained from the survey system, numerous health physics operations can be reliably performed with little human intervention using a fully automated system. Such operations can also significantly reduce time requirements for cask-receiving operations. 7 refs., 51 figs., 6 tabs.
A new technique, called tethered rocket, has been developed for testing in the penetration and/or impact modes. The technique involves tethering a rocket-motor assembly to an earth-fixed pivot so that the resulting semicircular arc delivers a payload to a precise impact point. Discussions are presented which describe the analytical and experimental activities of the tethered rocket technique. A series of analytical models has been integral to the success of the tethered rocket development. The analytic results were verified by testing. The tests demonstrated the viability of the technique for penetration and/or impact testing. Also included is a discussion of potential applications of the method. 18 refs., 53 figs., 17 tabs.
Cracking, craters, spotty damage (discoloration), and missing chunks of material have been observed on limiters and along the midplane of tokamak inner walls. This damage is assumed to be due to runaway electron discharges. These runaway electrons have been predicted to range in energy from a few MeV to several hundred MeV. The energy density from the runaway electron discharges ranges from 10 to 500 MJ/m{sup 2} over pulse lengths of 5 to 50 msec. The PTA code package is a unique application of PATRAN, the Integrated TIGER Series, and ABAQUS for modeling high energy electron impact on tokamak first wall and limiter materials. The PTA code package provides a three-dimensional, time dependent, computational code package which predicts energy deposition, temperature rise, and damage on relevant fusion materials from runaway electrons. In this benchmark study, three experiments were modeled to validate the PTA code package. The first and third experiment simulated runaway electrons scattering through a plasma facing surface (graphite) into an internal structure (copper), and the second experiment tested the thermal and structural response from high energy electron impact on different fusion relevant materials. The PTA calculations compared favorably with the experimental results. In particular, the PTA models identified gap conductance, thermal contact, x-ray generation in materials, and the placement of high stopping power materials as key factors in the design of plasma facing components that are resistant to runaway electron damage. 13 refs., 40 figs., 3 tabs.
We have determined experimentally the Shielding Effectiveness (SE) at microwave frequencies of various types of single- and double-braided cables and connectors typical of systems that have been hardened to electromagnetic fields. This report describes a laboratory-sized reverberation chamber and the techniques used to measure the SE of several interconnecting components. Graphical results are presented in the report, along with smoothed overlay plots for each category of measurements. The overlay plots indicate the general trends in the raw data and highlight the differences between tested components. 7 refs., 22 figs.
This report describes a statistical model for field amplitudes within a mode-stirred chamber. The parameters of the probability density function for field amplitudes are estimated by means of maximum likelihood. The accuracy of these parameters is specified as a function of the amount of data used. An experimental investigation of the possibility of using an existing electromagnetic shield room as a mode-stirred chamber is described. The physical alterations of the chamber and the instrumentation are summarized. Descriptions of the tests results are reported. The tests were conducted to determine: the unloaded and loaded Q of the chamber, descriptive statistics of the electromagnetic fields, correlation distances of the fields in frequency, tuner angle, and spatial position, and the possibility of using frequency stirring as an alternative to mechanical stirring. 10 refs., 20 figs., 10 tabs.
High-quality recording of an oscilloscope waveform is usually made on photographic film. Achieving high quality, especially in a possible radiation environment and with fast sweep speeds, requires a thorough understanding of all aspects of the imaging and recording processes. This paper represents a compilation of techniques and procedures to achieve optimum oscilloscope imagery under adverse conditions and in an environment where unwanted radiation is a possibility. 10 figs., 1 tab.
Structural system identification methods are analytical techniques for reconciling test data with analytical models. However, for system identification to become a practical tool for engineering analysis, the estimation techniques/codes must communicate with finite element software packages without intensive analyst intervention and supervision. This paper presents a technique used to integrate commercial software packages for finite element modeling (MSC/NASTRAN), mathematical programming techniques (ADS), and linear system analysis (PRO-MATLAB). The parameter estimation techniques and the software for controlling the overall system were programmed in PRO-MATLAB. Two examples of application of this software using measured data are presented. The examples consist of a truss structure in which the model form is well defined, and an electronics package whose model form is ill-defined since it is difficult to model with finite elements. A comparison of the resulting updated models with the experimental data showed significant improvement. 22 refs.
A Level II/III probabilistic risk assessment (PRA) has been performed for N Reactor, a Department of Energy (DOE) production reactor located on the Hanford reservation in Washington. The accident progression analysis documented in this report determines how core damage accidents identified in the Level I PRA progress from fuel damage to confinement response and potential releases the environment. The objectives of the study are to generate accident progression data for the Level II/III PRA source term model and to identify changes that could improve plant response under accident conditions. The scope of the analysis is comprehensive, excluding only sabotage and operator errors of commission. State-of-the-art methodology is employed based largely on the methods developed by Sandia for the US Nuclear Regulatory Commission in support of the NUREG-1150 study. The accident progression model allows complex interactions and dependencies between systems to be explicitly considered. Latin Hypecube sampling was used to assess the phenomenological and systemic uncertainties associated with the primary and confinement system responses to the core damage accident. The results of the analysis show that the N Reactor confinement concept provides significant radiological protection for most of the accident progression pathways studied.
A new gridless electrostatic field solver which utilities Fourier decomposition in the azimuthal coordinate has been developed and tested. The scaling with the number of simulation particles is N log N. This algorithm has been implemented in the BUCKSHOT code, which originally used a direct summation algorithm with N{sup 2} scaling. The Fourier decomposition in the new algorithm is done about the center of mass of each species, thus nonlinear ion hose physics is included in the m = O mode. Higher order modes describe non-axisymmetric profile changes. The breakeven point between the new solver and the direct summation algorithm is about N = 64 particles per species when up to m = 2 Fourier modes are kept. For a typical ion hose simulation with 256 particles per species the new solver is faster by a factor of about 2.7. 8 refs., 11 figs.
In order to generate a lithium vapor on the anode surface within PBFA II, an electrically insulating, lithium-coated substrate is required. One approach for providing this lithium source is the ceramic-option anode. This anode consists of two halves, equatorially split, each containing an insulating ceramic insert onto which a lithium-bearing film is sputtered. A lithium vapor is generated by ohmically pulse heating this film to 1500 K. The half-anode structure required to produce this vapor consists of a ceramic insulator, steel housing, and disk conductors. This report describes the design and fabrication of these separate components and the procedures required to join them to form the half-anode assembly. In addition, appendices are included which contain detailed drawings and specifications for these operations. 5 refs., 10 figs.
This report describes standard design criteria for and intrabuilding and interbuilding telecommunications wiring system to provide voice and open data services to facilities at Sandia National Laboratories, Albuquerque.
The US Department of Energy's (DOE) Waste Isolation Pilot Plant (WIPP) must comply with EPA regulation 40 CFR Part 191, Subpart B, which sets environmental standards for radioactive waste disposal. The regulation, Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (hereafter referred to as the Standard), was vacated in 1987 by a Federal Court of Appeals and is underground revision. By agreement with the Sate of New Mexico, the WIPP project is evaluating compliance with the Standard as promulgated, in 1985 until a new regulation is available. This report summarizes the early-1990 status of Sandia National Laboratories' (SNL) understanding of the Project's ability to achieve compliance. The report reviews the qualitative and quantitative requirements for compliance, and identifies unknowns complicating performance assessment. It discusses in relatively nontechnical terms the approaches to resolving those unknowns, and concludes that SNL has reasonable confidence that compliance is achievable with the Standard as first promulgated. 46 refs., 7 figs.
The authors describe the progress that has led to the triggering of high-power photoconductive semiconductor switches (PCSSs) with laser diodes. An 850 W optical pulse from a laser diode array has been used to trigger a 1.5 cm long switch that delivered 8.5 MW to a 38.3 Ω load. Using 166 W arrays, a 2.5 mm long switch has been triggered, delivering 1.2 MW with 600 ps risetimes at pulse repetition frequencies of 1 kHz. These 2.5 mm long switches were tested for pulse lifetime and survived 105 pulses at 1.0 MW levels. In single pulse operation up to 600 A has been switched with laser diode arrays. The goal is to switch up to 5 kA in a single shot mode and up to 100 MW repetitively at up to 10 kHz. It is pointed out that these goals are feasible since the switches can be used in parallel or in series.
This report provides system designers with basic human factors information and guidelines to help in the selection of manual data input devices. The selection of such devices is important with respect to the environment in which the device with be used, speed of data entry required, error potential, and the user friendliness of the candidate devices. The report reviews several of the most commonly used data input devices and provides a description of each, experimental evaluations, and observations and recommendations based on review of the data. In addition, the appendix presents an input device matrix that gives general guidance concerning input devices and the physical and mission environment in which they might be used. Additional assistance should be requested from Sandia National Laboratories (SNL) Human Factors Personnel. 23 refs., 13 figs.
Concerns about energy spreads due to degradation of 1.1-MV, 34-ns duration accelerating cavity repeating pulse shapes have resulted in improving the 24-switch trigger system for the ET-2 cavity, and identifying critical factors in the cavity design that affect the pulse shape. The authors summarize the improvements (completed and proposed) for the existing ET-2 cavity and the status of the design analysis and modeling of accelerating cavities. A relativistic electron beam (REB) injector for the RLA is being installed which will provide a higher amplitude
As a crosslinking polymer cures, dramatic changes in molecular architecture occur. These structural changes in turn affect the viscoelastic behavior of the material. At a critical extent of reaction (the gel point), the polymer undergoes a transition from a viscous liquid to an elastic solid. We have monitored the evolution of structure and viscoelasticity in the most common epoxy encapsulant used at Sandia, diethanolamine-cured Epon 828. The structure evolves according to percolation theory, and the viscoelasticity evolves according to our dynamic scaling theory for branched polymers. 9 refs., 12 figs.
Calculations are performed to predict the distribution of the (5p){sup 5}(5d)--(5p){sup 5}(6p)emission cross section in Xe in a strong magnetic field. For isotopes with no nuclear magnetic moment, the question is the calculation of Lande g factors. This is done with wavefunctions obtained by diagonalizing the electrostatic interaction in jj coupling, leading to reasonable accurate Lande g factors. For levels described by quantum numbers J and M, the Zeeman interaction is always diagonal in M, and with a 6 kG magnetic field the Zeeman interaction is effectively diagonal in J (the non-diagonal matrix elements are negligible), so the resulting cross section calculations are simple. For the isotopes with non-zero magnetic moments, one must determine the dipole and quadrupole hyperfine splitting coefficients. To do this and to improve the overall fit of the calculated and measured energy levels, it was necessary to include configuration interaction between terms of the (5p){sup 5}(5d) and (5p){sup 5}(6s) configurations. Comparisons are made between these calculated hyperfine parameters and experiment. Hyperfine splittings are tabulated as are the cross sections and energy shifts due to hyperfine interaction in each transition. When hyperfine interaction is included and levels are characterized by the quantum numbers F and M{sub F}, the Zeeman interaction is diagonal in M{sub F} but different F. All these effects were included in the calculations leading to a particularly rich spectrum for Xe(131) with I = 3/2. For example, the (5p){sup 5}(5d){sub J} = 4{minus}(5p){sup 5}(6p){sub J} = 3 transition is split into approximately 336 components. 21 refs., 3 figs., 12 tabs.
This annual report summarizes progress which has been made in Fiscal Year 1989 on this program of geotechnology for tight gas reservoirs. Most of the studies are an outgrowth of the results and experience from the Multiwell Experiment -- an unprecedented investigation of western gas reservoirs typical of the Mesaverde Formation. Results are presented in the following study areas: (1) tectonism, subsidence and fracturing of these reservoirs, (2) mechanism for the formation of regional fractures in flat-lying basins, (3) the case against natural hydraulic fracturing, (4) characterization and implications of dickite-mineralized fractures, (5) significance of coring-induced fractures, (6) determination of an effective stress law for permeability in tight sandstones, and (7) stress azimuths for two well sites in the Piceance Basin. In addition, technology transfer aspects and impact of the Multiwell Experiment are summarized. 27 refs., 28 figs., 1 tab.
This study was performed under FUTURE LOOK, a joint Defense Nuclear Agency/Department of Energy (DNA/DOE) sponsored study. The intent of FUTURE LOOK is to identify and develop means of providing requisite security and survivability to the Non-Strategic Nuclear Forces (NSNF) in the Twenty-First Century. Our current thinking about the future world in Europe is summarized. In this report we develop four scenarios/stockpile cases to cover the spectrum of potential happenings in Europe; we also develop general security and survivability implications and recommendations for each case. The four cases are: (1) a substantially reduced (factor of 2--10) European stockpile; (2) a near-zero stockpile, with no Army weapons remaining in Europe; (3) current stockpile in Europe remains; and (4) current stockpile numbers remain, but aggressive modernization is allowed. We plan to use the information in this report to assist in developing detailed security and survivability options as part of our follow-on to FUTURE LOOK studies. 8 refs., 6 tabs.
The purpose of this computer program is to serve as a tool in the daily operation of the R D storage function. This menu-driven, interactive program was written in DBase III+ for use on an IBM PC-XT computer to efficiently store items in a minimum space, inventory, locate, report, withdraw and record the activities in a history file. A drive path is utilized in numbering each storage location to minimize the distance and time required to store and retrieve an item. An empty-space listing is available for a limited inventory.
The United States Department of energy, after considering a number of alternative disposal methods for radioactive wastes in the United States, Proposed that these wastes should be disposed of in deep geologic repositories. This alternative is currently being developed at the Waste Isolation Pilot Plant (WIPP), for transuranic waste, and investigated at Yucca Mountain, for spent power-reactor fuel and vitrified high-level waste, the latter resulting principally from defense activities. In addition, a research program on subseabed disposal was active from 1973 until 1987 but is currently suspended. The two deep-geologic disposal projects are discussed in detail and the subseabed-disposal research project is briefly summarized. 28 refs., 39 figs., 4 tabs.
Thermal and mechanical models for intact and jointed rock mass behavior are being developed, verified, and validated at Sandia National Laboratories for the Yucca Mountain Project. Benchmarking is an essential part of this effort and is the primary tool for verifying engineering software used to solve thermomechanical problems. This report presents the results of the second phase of the first thermomechanical benchmark exercise. In the first phase of this exercise, three finite element codes for nonlinear heat conduction and one coupled thermoelastic boundary element code (HEFF) were used to solve the thermal portion of the benchmark problem. The boundary element code HEFF was used in this exercise because it calculates a solution to the coupled thermal/elastic problem using an approximate analytical method and, thus, provides a means of comparing the finite element solutions with a solution obtained by an independent method. The results from the thermal analysis were then used as input to the second phase of the analysis, which consisted of solving the structural portion of the benchmark problem using a linear elastic rock mass model. Five different structural codes, JAC, SPECTROM-31, VISCOT, and HEFF, were used by the participants in this portion of the study. The problem solved by each code was a two-dimensional idealization of a series of drifts with the approximate dimensions of the proposed design for vertical emplacement of nuclear waste at Yucca Mountain. 6 refs., 74 figs., 4 tabs.
Dual focus laser velocimetry (L2F), photographic techniques, and pressure measurements were used to investigate particle and flame characteristics of a high velocity oxygen/fuel (HVOF) flame spray gun known as CDS''. Velocities of alumina, tungsten carbide, and Triballoy particles within the HVOF effluent stream have been measured using L2F techniques. Photographs of the exiting gases were used to determine the local Mach numbers within the gas stream. Measurements of Mach angles in the photographs were used to determine the actual gas velocity in the free jet of the device. Pressure measurements were made on the HVOF device which enabled calculations of the gas content, R, and the specific heat ratio, {kappa}. These calculations combined with estimates of gas temperature are used to calculate gas velocities at Mach 1 (nozzle exit). The HVOF device was used to produce dense WC/12 wt. % Co and Triballoy T-400 coatings. For the two gas flow conditions examined, higher hardness values and densities were observed for coatings deposited at the higher gas flow rates.
This report documents the characterization and development of the 381558 (2N6193JTXV), a medium power PNP silicon transistor designed for switching and wide band amplifier applications. The 2N6193JTXV is manufactured by Motorola. 50 figs., 6 tabs.
This report documents the characterization and development of the 381568 (2N5339JTXV), a medium power NPN silicon transistor designed for switching and wide band amplifier applications. The 2N5339JTXV is manufactured by Motorola. 50 figs., 6 tabs.
This report describes the major hardware and software components of the HERMES III Control and Monitor System at the Simulation Technology Laboratory (STL) at Sandia National Laboratories. The HERMES III Control and Monitor System is a computer controlled system that controls and monitors the charging, arming, and firing of the HERMES III accelerator. This documentation is intended to be a general introduction to the system for engineers and technicians involved in the maintenance and modification of the system. It may also be useful to persons interested in designing and constructing a similar control system. This report collects many of the documents produced throughout the project and directs the reader toward other documents written for this project.
This report describes the components and installation of the Oxygen Deficiency Monitor System (ODMS) at the Simulation Technology Laboratory (STL) at Sandia National Laboratories. The ODMS presently monitors the oxygen concentration of the ambient air in the lower levels of the laboratory where air circulation may be insufficient to disperse gases that may settle and accumulate creating an oxygen-deficient environment. The intent of this report is to provide a general introduction to the system for personnel involved in the maintenance and modifications of the system and may be useful to people interested in installing a similar system. This will report describe the hardware components, installation considerations, operation, and maintenance of the system. 6 refs., 5 figs.
The literature is reviewed on the amount and the characteristics of particulate material (crud), that is deposited on Light Water Reactor (LWR) fuel rods and assemblies. Currently available data on crud composition, specific activity, spallation mechanisms, potential environmental release, and particle size distributions is considered. In addition, literature that pertains to the possible impact of crud on repository operations is surveyed. This report consists of rather extensive excerpts from the published literature on crud that may have a bearing on repository risk assessment. Commentary on the possible effects of crud on repository operations and the applicability of available crud information to repository risk analyses is included. In addition, estimates are made of the quantity of crud that might be available for release during the different phases of repository operations. Using these estimates, the total effective dose equivalent is determined at several distances from a release point.
This 1989 report contains monitoring data from routine radiological and nonradiological environmental surveillance activities. Summaries of significant environmental compliance programs in progress such as National Environmental Policy Act documentation, environmental permits, environmental restoration, and various waste management programs for Sandia National Laboratories in Albuquerque (SNL, Albuquerque) are included. The maximum offsite dose impact was calculated to be 8.8 {times} 10{sup {minus}4} mrem. The total Albuquerque population received a collective dose of 0.097 person-rem during 1989 from SNL, Albuquerque, operations. As in the previous year, SNL, Albuquerque, operations in 1989 had no adverse impact on the general public or on the environment. 46 refs., 20 figs., 31 tabs.
This report summarizes the environmental surveillance activities conducted by Environmental Protection Agency (EPA) and Reynolds Electrical and Engineering Company (REECo) for the Tonopah Test Range (TTR) operated by Sandia National Laboratories (SNL). Other environmental compliance programs such as National Environmental Policy Act of 1969 (NEPA), environmental permits, environmental restoration, and waste management programs are also included. The maximum offsite dose impact from 1989 operations was 8.7 {times} 10{sup {minus}4} mrem as a result of an unusual occurrence. The population received a collective dose of 1.2 {times} 10{sup {minus}5} person-rem from this incidence, while the same populations received 4.94 person-rem from natural background radiation. The 1989 SNL, TTR operations had no adverse impact on the general public or the environment. 18 refs., 2 figs., 14 tabs.
Drillholes H-11b1, H-11b2, and H-11b3 were drilled from August to December 1983 for site characterization and hydrologic studies of the Culebra Dolomite Member of the Upper Permian Rustler Formation at the Waste Isolation Pilot Plant (WIPP) site in southeastern New Mexico. In October 1984, the three wells were subjected to a series of pumping tests designed to develop the wells, provide information on hydraulic communication between the wells, provide hydraulic properties information, and to obtain water samples for quality of water measurements. Based on these tests, it was determined that this location would provide an excellent pad to conduct a convergent-flow non-sorbing tracer test in the Culebra dolomite. In 1988, a fourth hole (H-11b4) was drilled at this complex to provide a tracer-injection hole for the H-11 convergent-flow tracer test and to provide an additional point at which the hydraulic response of the Culebra H-11 multipad pumping test could be monitored. A suite of geophysical logs was run on the drillholes and was used to identify different lithologies and aided in interpretation of the hydraulic tests. 4 refs., 6 figs., 6 tabs.
A computer model for simulating the explosive dispersal of a fuel agent in the far-field regime is described and is applied to a wide variety of initial conditions to judge their effect upon the resulting fuel/air cloud. This work was directed toward modeling the dispersal process associated with Fuel-Air-Explosives devices. The far-field dispersal regime is taken to be that time after the initial burster charge detonation in which the shock forces no longer dominate the flow field and initial canister and fuel mass breakup has occurred. The model was applied to a low vapor pressure fuel, a high vapor pressure fuel and a solid fuel. A strong dependence of the final cloud characteristics upon the initial droplet size distribution was demonstrated. The predicted fuel-air clouds were highly non-uniform in concentration. 18 refs., 86 figs., 4 tabs.
The Vindicator ETW-250 taut wire system combines a physical taut wire barrier with an intrusion detection sensor network. The sensor wires deter and/or slow physical entry into protected areas. The sensors themselves generate an alarm if the sensor wires are pulled, spread, cut, or climbed on. This physical motion is converted into an electrical waveform that is analyzed by the processor. The processor then determines if this motion is within the pre-programmed parameters. If it is not, an alarm is generated through a relay back to the monitoring station. Small changes, such as those caused by temperature, are rejected. Installation and testing are described.
Containment and Surveillance (C/S) equipment, which is used in international safeguards applications, is normally expected to operate unattended within a facility in a host country for extended periods of time. To ensure that this equipment consistently provides high-quality data, the equipment used to ensure the data's integrity must be highly reliable and tamper-resistant. Although designed specifically for use by the International Atomic Energy Agency to comply with the Non-Proliferation Treaty, the equipment has potential applications for both bilateral and multilateral verification schemes for other treaties. This report describes C/S equipment that has been developed by Sandia National Laboratories, and discusses its potential applications. This equipment includes surveillance equipment, seals, monitoring equipment, and authentication equipment. 16 refs., 20 figs.
Waste Isolation Pilot Plant (WIPP) sealing program results are embodied in the initial seal system strategy and reference design. The design provides a common basis for calculations and analyses so that results can be compared directly. The sealing strategy combines both long- and short-term seal components. Crushed salt is the principal long-term barrier to fluid flow. Short-term seal components are used until creep consolidation is sufficient. Concretes developed specifically for WIPP seals and a swelling clay material that exhibits low permeability to WIPP groundwater and brine have been chosen for the short-term components. A body of evidence exists showing the stability of these materials for the length of time they are required to function. Reference designs are described and drawings are shown for each of the principal multi-component seals. Confidence in the sealing strategy and the reference designs resulted from a combination of laboratory tests, numerical modeling, and in situ demonstrations. The sealing strategy, materials, and designs for the WIPP repository are consistent with the concepts and designs proposed previously for other national and international waste management programs. Past accomplishments and planned activities in the sealing program will produce a detailed conceptual design for the seal system and a seal system performance model. 48 refs., 11 figs., 6 tabs.
In the course of communication circuit design at Sandia National Laboratories, a set of communication symbols was created to aid, and hopefully standardize, the design process. These symbols, which allow the designer to build a circuit using black boxes, simplify circuit design and documentation. They also provide a standard set to help minimize interpretation problems among circuit designers. The symbols can be used to represent various devices in a circuit, such as modems, computers, terminals, encryption devices, converters, etc. When using these symbols to design communication circuits, the contours of each symbol show which devices interface together. Mismatch device contours indicate the need for another element (such as a null modem) between the two devices. In addition, the propagation of clock, data, and control signals through the circuit can be represented. Clocking modes on synchronous components (modems, multiplexers, etc.) and signal line crossovers can also be determined from the drawings during the design process. 30 figs.
A series of test has evaluated the current-carrying characteristics of several proposed detonator strong safety link (DSSL) drive cables to conduct current into an electrically simulated radiation case enclosure. The drive cables tested included a dielectric cable made up of either one or two braided Kevlar threads in a polysulfone sleeve, an existing DSSL conductive drive cable similar to a bicycle shift cable, with and without an external ground-strap diversion feature, and the flex circuit hook assembly used for DSSL instrumentation purposes. Each of the test samples was connected to a 200-kV, 30-kA Marx generator and terminated inside an electrically simulated radiation case enclosure. Two lengths of drive cables (4 and 13 in.) within the simulated radiation case were tested for each type. The results indicate that the conductive drive cables without an external short-circuit diversion feature conducted about 5 to 9 times as much current into the simulated radiation case as either the dielectric drive cables or the conductive drive cables with an external short-circuit feature. Surprisingly, the flex circuit hook assemblies, both the short and long cables, conducted nearly 100% of the available current into the simulated radiation case enclosure. The next series of experiments will repeat the tests at the SNL Lightning Facility in order to scale the results up to the maximum lightning threat levels of 200 kA. 18 figs., 1 tab.
Proceedings of SPIE - The International Society for Optical Engineering
Zeigler, John M.
Little work has been performed to characterize the exposure sensitivity, contrast, and tone of candidate resists for photon energies between 100-300 eV, the range in which projection soft x-ray lithography will be developed. We report here the characterization of near-edge x-ray absorption fine structure (NEXAFS) spectra, exposure sensitivity, contrast, and post-exposure processing of selected polysilane resists at photon energies close to the Si L2,3 absorption edge (100 eV). We find absorption resonance features in the NEXAFS spectra which we assign to excitation into Si-Si and Si-C σ∗ orbitals. Using monochromatized XUV exposures on the Si-Si σ∗ resonance at 105 eV, followed by solvent dissolution development, we have measured the exposure sensitivity curves of these resists. We find sensitivities in the range of 600-3000 mJ/cm2 and contrasts in the range from 0.5-1.4, depending on the polysilane side chain. We have also performed exposure sensitivity measurements at 92 eV, below the edge. Sensitivity decreases slightly compared to 105 eV exposures and the saturation depth and contrast both increase, as expected. We find also that exposing resist films to oxygen after XUV exposure, but before development, increases the sensitivity markedly.
The solderability of 60Sn40Pb solder on Kovar was examined as a function of surface-cleaning procedure, flux, and solder-bath temperature. Organic-acid fluxes were more effective at lowering the contact angle than was a mildly activated, rosin-based (RMA) flux on chemically etched Kovar. The contact angles were as low as 29{degree} {plus minus} 5{degree} as compared to 61{degree} {plus minus} 11{degree}, respectively. Varying the solder temperature through the range of 215{degree}C to 288{degree}C caused an insignificant change in the contact angle for the RMA flux and a decrease of the contact angle for a candidate water-based, organic-acid flux. The dilution strength of the flux and the elapsed cleaning time significantly influenced the solder-flux interfacial tension, {sub {gamma}LF}. T-peel strengths of Kovar-60Sn40Pb-OFHC copper joints had a low correlation with the contact angle derived from the solderability experiments. The results of the solderability tests and the T-peel mechanical tests, and subsequence microanalysis of the as-soldered and T-peel samples revealed that the best results for the RMA flux were achieved by using an electropolishing procedure and a solder temperature of 240{degree}C to 260{degree}C. A relatively low contact angle of 31{degree} {plus minus} 2{degree} was observed, with no evidence of cracking or thick-film intermetallic formation at the Kovar-solder interface. T-peel strengths were nominally 9.4{degree} {plus minus} 0.5 {times} 10{sup 6} dyn/cm. 21 refs., 36 figs., 11 tabs.
Parachute system performance issues such a turnover and wake recontact may be strongly influenced by velocities induced by the wake of the delivering aircraft, especially if the aircraft is maneuvering at the time of parachute deployment. The effect of the aircraft on the parachute system is a function of the aircraft size, weight, and flight path. In order to provide experimental data for validation of a computer code to predict aircraft wake velocities, a test was conducted in the NASA 14 {times} 22 ft wind tunnel using a 5.78% model of the B-1B strategic bomber. The model was strut mounted through the top of its fuselage by a mechanism which was capable of pitching the model at moderate rates. In this series of tests, the aircraft was pitched at 10{degree}/sec from a cruise angle of attack of 5.3{degree} to an angle of attack of 11{degree} in order to simulate a 2.2g pullup. Data were also taken for the subsequent pitch down sequence back to the cruise angle of attack. Instantaneous streamwise and vertical velocities were measured in the wake at a number of points using a hot wire anemometer. These data have been reduced to the form of downwash coefficients which are a function of the aircraft angle of attack time-history. Unsteady effects are accounted for by use of a wake convection lag-time correlation. 12 refs., 59 figs., 4 tabs.
This report presents the concept of formalizing the elicitation and use of expert judgment in the performance assessment of high-level radioactive waste (HLW) repositories in deep geologic formations. The report begins with a discussion of characteristics (advantages and disadvantages) of formalizing expert judgment examples of previous uses of expert judgment in radioactive waste programs, criteria that can assist in deciding when to formalize expert judgment, and the relationship of formal use of expert judgment to data collection and modeling. The current state of the art with respect to the elicitation, use, and communication of formal expert judgment is presented. The report concludes with a discussion on potential applications of formal expert judgment in performance assessment of HLW repositories. 93 refs.
As part of a Department of Energy/Commission of European Communities (DOE/CEC) cooperative program, Sandia National Laboratories was asked to develop a portable ultrasonic seal pattern reading system. The system consists of a data acquisition box (DAB), a mechanical reading head, and a portable IBM-compatible PC linked to the DAB by a serial RS-232C communication link. This manual focuses on the DAB subsystem. 8 refs., 13 figs., 8 tabs.
MCPRAM (Monte Carlo PReprocessor for AMEER), a computer program that uses Monte Carlo techniques to create an input file for the AMEER trajectory code, has been developed for the Sandia National Laboratories VAX and Cray computers. Users can select the number of trajectories to compute, which AMEER variables to investigate, and the type of probability distribution for each variable. Any legal AMEER input variable can be investigated anywhere in the input run stream with either a normal, uniform, or Rayleigh distribution. Users also have the option to use covariance matrices for the investigation of certain correlated variables such as booster pre-reentry errors and wind, axial force, and atmospheric models. In conjunction with MCPRAM, AMEER was modified to include the variables introduced by the covariance matrices and to include provisions for six types of fuze models. The new fuze models and the new AMEER variables are described in this report.
The purpose of this report is to summarize for the record the objectives, planning, progress, and documentation of excavating Brine Inflow Room Q and implementing an initial set of Room Q tests. The Room Q tests were designed primarily to test the scale-up accuracy of the current brine inflow model by providing data on brine flow from the host rock salt to a large-scale excavation in the Waste Isolation Pilot Plant (WIPP). Data from these tests will also be used to reduce uncertainties in flow parameters and evaluate proposed mechanistic models. Room Q was excavated with a tunnel boring machine. The initial tests were implemented to measure brine flow parameters and room closure. Pore pressure, permeability, and brine inflow were measured with 15 tools emplaced in boreholes above, below, and on the north side of the room at a station 75 feet into the host rock from the entrance to the room. These measurements were made before, during, and after Room Q was bored to obtain data on the responses in the host rock to the boring process. Closure measurements were started almost immediately after excavation progressed past each measurement station. The designs, timing, sequence, procedures, and as-built records for these tests were documented in Sandia National Laboratories WIPP Quality Assurance files and Westinghouse WIPP Engineering records. 21 refs., 5 figs., 5 tabs.
CTH is a software system under development at Sandia National Laboratories (SNL) to model multidimensional, multi-material, large deformation, strong shock wave physics. One-dimensional rectilinear, cylindrical, and spherical meshes; two-dimensional rectangular, and cylindrical meshes; and three-dimensional rectangular meshes are currently available. A two-step Eulerian solution scheme is used with these meshes. The first step is a Lagrangian step in which the cells distort to follow the material motion. The second step is a remesh step where the distorted cells are mapped back to the original Eulerian mesh. CTH has several thermodynamic models that are used for simulating strong shock, large deformation events. Both tabular and analytic equations of state are available. CTH can model material strength, high explosive detonation, fracture, and motion of fragments smaller than a computational cell. The material strength model is elastic perfectly plastic with thermal softening. A programmed burn model is available for computing the thermodynamic properties of explosive detonation. The Jones-Wilkins-Lee equation of state is available for modelling high explosive reaction products. Fracture can be initiated based on pressure or principle stress. A special model is available for moving fragments smaller than a computational cell with the correct statistical velocity. 7 refs.
Conference Record of the IEEE Photovoltaic Specialists Conference
Chiang, C.J.
A description is given of Sandia's CONCEPT-90 module, which represents a novel type of point-focus photovoltaic concentrator module designed for improved safety, reliability, and performance, and for ease of component fabrication and module assembly. These improvements will combine to decrease the cost of electricity produced by this type of concentrator module. Unique features of the CONCEPT-90 module include encapsulated cell assemblies, simple flat components, and integral use of plastics. The first prototype of this module has been made using back-contact silicon concentrator cells and refractive secondary optical elements. The first prototype module is described, and results from outdoor tests are presented.
The Software Utilities Package for the Engineering Sciences (SUPES) is a collection of subprograms which perform frequently used non- numerical services for the engineering applications programmer. The three functional categories of SUPES are: (1) input command parsing, (2) dynamic memory management, and (3) system dependent utilities. The subprograms in categories one and two are written in standard FORTRAN-77, while the subprograms in category three are written to provide a standardized FORTRAN interface to several system dependent features. 2 refs.
Magnet configurations are found that limit the 6-MeV electrons threatening satellite electronics to <1% of the incident flux. Successful configurations of permanent magnets and electromagnets require magnetic energies of {approximately}8 to 12 kJ to protect each liter of electronics volume. The fundamental strength of materials leads to a required minimum mass of {approximately}48 to 64 kg/liter to support the magnetic pressure. With the electronics requiring {approximately}5 liters, several hundred kilograms are needed for this support. Except for protecting small apertures, magnetic shielding provides little, if any, advantage over that obtained by coating with an equivalent mass using traditional methods. 7 refs., 9 figs., 1 tab.
Until recently, hydrologic characterization in closed sections of boreholes at the Waste Isolation Pilot Plant (WIPP) has relied on measurements of pressure and temperature to establish the permeability of the host geological formations. There were no provisions for monitoring tool compliance and salt creep resulting from borehole closure. The new permeability test tool used to characterize the WIPP underground facility has been equipped with a series of sensors to measure the movement of the tool with respect to the borehole and borehole wall movement. A FORTRAN program can interpret the output data from each test and calculate the change in borehole radius, test zone length, and test zone volume. These values provide a correlation of fluid compressibility and tool compliance with the permeability results derived from the test data. 4 figs., 3 tabs.
The evaluations and selected interim test results from eight different models of small (approximately 10 A) charge controllers are described. They are being subjected to a comprehensive test program including thorough electrical characterizations at selected temperatures, photovoltaic inputs, and load levels. After electrical characterizations, the charge controllers are divided into concurrent evaluation paths. One path consists of side-by-side operational system tests in which the charge controllers are installed in identical stand-alone PV systems. The other path consists of continuous environmental and electrical cycling in which the controllers are subjected to programmed electrical inputs, temperatures, and relative humidities. Recharacterizations of all controllers are performed on a periodic basis to detect changes in electrical performance. In addition, selected custom tests are performed on identical models to determine response to transients, installation issues, and system capabilities. The data presented include measured electrical characteristics of the controllers, temperature effects, operational performance, and interface measurements at the array, battery, and load.
The capabilities of a versatile Nd:YAG pulsed-laser system developed at Sandia National Laboratories for solar cell processing applications is described. The results of statistically based, multifactor experiments used to characterize the influence of laser-system process variables on patterns produced in silicon wafers and silicon-oxide layers are presented, and an initial assessment of laser-grooved solar cell processing conditions is given.
AlGaAs/GaAs solar cells are typically characterized as having relatively high interface recombination velocities at the heteroface. Some of the factors influencing the design of solar cell window layers are examined, and the effect of substituting InAlAs/GaAs superlattice alloys and InAlAs bulk alloys in place of AlGaAs is considered. Potential advantages are reduced surface recombination at the heterojunction, reduced thermionic emission into the window layer, thinner window layers, and reduced absorption in the window layer. Theoretical models predict a lower effective surface recombination velocity and a smaller acceptor activation energy for superlattice alloys. Experimental absorption data show that superlattice alloys have a lower absorption coefficient at short wavelengths near the UV roll off.
Drayer, D.D.; Sonnier, C.S.; Mangan, D.L.; Walford, F.
Facilities are now coming under Agency safeguards which have large amounts of nuclear material and/or nuclear material which is very difficult to access for reverification. Containment and Surveillance (C/S) technologies may be used to assist in resolution of this problem. This study examines the concept of redundant and independent C/S Systems, and discusses how these systems could be used to lower the need for remeasurement of materials which are difficult to access, or materials included in very large inventories. This paper dose not address increasing levels of C/S measures to protect different types of materials. However, the paper does discuss how redundant and independent C/S Systems will improve the reliability of safeguards information. Equipment which may be used in such systems, and examples of potential systems, are presented. Decisions on how much C/S equipment is enough for a given facility, or type of material, must be made by the inspectorate. 6 refs., 4 figs.
A Level III probabilistic risk assessment (PRA) has been performed for N Reactor, a Department of Energy (DOE) production reactor located on the Hanford reservation in Washington. The objectives of the PRA are to assess the risks to the public and the Hanford site workers posed by the operation of N Reactor, to compare those risks to proposed DOE safety goals, and to identify changes to the plant that could reduce the risk. The scope of the PRA is comprehensive, excluding only sabotage and operation errors of commission. State-of-the-art methodology is employed based largely on the methods developed by Sandia for the US Nuclear Regulatory Commission in support of the NUREG-1150 study of five commercial nuclear power plants. The structure of the probabilistic models allowed complex interactions and dependencies between systems to be explicitly considered. Latin Hypercube sampling techniques were used to develop uncertainty distributions for the risks associated with postulated core damage events initiated by fire, seismic, and internal events as well as the overall combined risk. The combined risk results show that N Reactor meets the primary DOE safety goals and compared favorably to the plants considered in the NUREG-1150 analysis. 36 figs., 81 tabs.
This report discusses the performance of commercial amorphous silicon modules used in photovoltaic power systems from 1985 through 1989. Topics discussed include initial degradation, reliability, durability, and effects of temperature and solar irradiance on peak power and energy production. 6 refs., 18 figs.
This report is the outcome of a study of the technical and procedural requirements which would need to be met if the Agency and facility operators were to agree that under certain circumstances the operator could remove or apply on Agency seal in the absence of an inspector. In the FRG and USA Support Programmes respectively an electronic seal (VACOSS) and a CCTV system (MIVS) have been developed. Through a joint project, an interface has been demonstrated which enables the seal data to be superimposed upon the surveillance data. This interface is briefly described in the appendix. A proposed application for this integrated system is to allow facility operators to carry-out some of the seal procedures normally performed by an inspector, thereby reducing the need for inspector presence at certain crucial times.
Thermal battery functional test data are stored in an HP3000 minicomputer operated by the Power Sources Department. A program was written to read data from a battery data base, compute simple statistics (mean, minimum, maximum, standard deviation, and K-factor), print out the results, and store the data in a file for subsequent plotting. A separate program was written to plot the data. The programs were written in the Pascal programming language. 1 tab.
This document describes the Nuclear Weapons Complex (NWC) detached'' CIM file header. The file header concept is defined and its form and content are specified. Guidelines for the use of file headers by the CIM community in the NWC are also included. This document is the result of the combined efforts of the Lead Laboratory and the NWC File Header Subgroup. It has evolved through a process of cooperation and compromise and represents a consensus view of the NWC.
At Sandia National Laboratories data engineering is the application of both the art and science aspects of engineering principles to the acquisition and storage of product-related test and traceability data and to the transformation of this data into useful information through data retrieval and analysis processes. This report describes the application of data engineering to the data systems that have been developed in support of production agency built or procured product. The production agencies that are addresses in this report include Mason Hanger, Amarillo, TX; GEND, Largo, FL, Allied Signal, KCD, Kansas City, MO; and Mount, Miamisburg, OH. Also discussed is the Weapon Evaluation Test Laboratory (7264)/Amarillo. The scope of the data engineering program for each production agency (or test facility) is presented along with the interfaces and constraints. The present contractors' data system is described and system limitations and future plans are discussed. 7 refs., 38 figs.
BUCKL is an inexpensive x-ray deposition computer code which considers one-dimensional transport and accounts for two-dimensional effects in a buckling approximation. This manual contains input instructions and sample input.
A variety of geomechanical analyses are presented that support the WIPP project. The scale of the analyses ranged through laboratory experiments, small-scale in-situ tests, large-scale in-situ tests, underground rooms, shafts and shaft keys, and multi-room panels. The structural behavior of underground rooms, shafts, and experiments was investigated using the finite element method. Both two and three dimensional analyses simulated the time-dependent behavior of the salt host rock. Two different constitutive models were used to represent the creeping motion of the salt. The investigations aided in experimental planning, code validation, and assessing excavation responses for safety and performance assessment. This report compiles ten different structural analyses which assess the performance of excavations and experiments located at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM. Chapter 2 discusses the constitutive models used to represent the salt behavior. Each of Chapters 3 through 12 presents an analysis. Chapter 13 concludes the report. 36 refs., 48 figs., 17 tabs.
An interactive computerized and automated system to provide environmental control for atmospheric corrosion experiments has been added to the FACT, as well as computerized data acquisition for sample weighing. The FACT allows control of corrosive gas concentrations to simulate industrial atmospheric conditions and requires constant manual adjustment to provide a stable test environment. Because constant manual adjustment is impractical, we have automated this facility to achieve the desired stability. This system incorporates an IBM PC AT using Keithley's Series 500 hardware and Quick500 software development environment to calibrate gas analyzers, and to monitor exposure time, test chamber temperature, and gas concentrations. A second PC has been connected to a Mettler M3 microbalance through an IEEE-488 interface communicating under Lotus Measure. Weighings with a sensitivity of 1 {times} 10{sup {minus}6} gram are transferred directly into a Lotus 123 spreadsheet where the data can then be easily manipulated and plotted. Under computer control, the FACT can now run unattended for more than a week and maintain much better control over gas concentrations (200 {plus minus} 5 ppb and 10 {plus minus} 0.5 ppb for NO{sub 2} and H{sub 2}O and H{sub 2}S, respectively) than was possible with manual control (100 {plus minus} 25 ppb for either gas), after initial stabilization. 9 figs.
The Linear Explosive Shaped Charge Analysis (LESCA) code is used to analytically model and optimize the design of a linear shaped charge (LSC). A variety of LSCs are initially modeled with the LESCA code, and the predicted jet penetration versus standoff data are compared to experimental data. The LSCs varied in explosive loading size form 600 to 10,500 grains per foot. The LSC liner material for this study was cooper. The variables optimized in this study included the LSC apex angle, liner thickness, explosive width, and explosive width, and explosive height. 8 ref., 24 figs.
The PCP PHEMTO-CHEM 100 ion mobility spectrometer (IMS) exhibits a number of characteristics that affect its performance for the quanititative and qualitative analysis of explosives in solution and in the gas phase. These characteristics, as well as modifications to the system that will either eliminate, or reduce, the extent of some problems associated with these characteristics, are described. Also described are other aspects of the operation and performance of this system. 9 refs., 10 figs., 1 tab.
This report discusses the purpose and requirements that were established for the data logger at the 34-m diameter, research- oriented vertical axis wind turbine, the Test Bed, which Sandia National Laboratories built at Bushland, Texas. The data logger is a minicomputer-based system that collects data from 35 channels, displays the collected data, and records them on a hard disc. Both the hardware and software that make up the data logger are also described, and the operator's instructions and the operating system commands and procedure files are appended. The data logger is used to obtain long-term data to characterize the wind at the site of the turbine, record the performance data of the control system, obtain a continuous record of events at the test sire, consolidate displays for the test engineer, and provide a display of current information for visitors to the site. 7 refs., 3 figs., 4 tabs.
Analytical equations for barrel-tamped explosively accelerated flyer plates are used to generate graphical solutions to flyer problems. Given the problem geometrical dimensions, explosive weight, detonation velocity, explosive exponent, barrel-tamping weight, and flyer weight, the graphical representation of the calculated data allows for a fast approximation of the final or maximum flyer plate velocity. Graphically obtained flyer velocities are compared to experimentally published data. The graphical solution for flyer velocity is particularly useful when a computer is not available. The graphical representation of the various barrel-tamped flyer parameters results in a parametric study which illustrates the effect on final flyer velocity in varying parameters. The graphical analysis scheme can be used with any explosive, tamper and flyer materials. 15 refs., 12 figs., 4 tabs.
This report presents the results of numerical modeling of the electron beam generation, transport, and conditioning in the Sandia accelerators RADLAC, IBEX, and RLA for the year 1989. The codes used were the particle code MAGIC, the trajectory code TRAJ, and some preliminary work with the 3-D code Quicksilver. The results are mostly in the areas of injector design, beam propagation in IFR channels and B{sub {Theta}} cells, and emittance measurements. The energy range of these electron beams is from 1 MeV to 20 MeV. 16 refs., 42 figs.
Finite-difference time-domain (FDTD) codes can, in principle, be used to determine the electromagnetic response of complex scatterers. However, the extent to which structural details can be accommodated is limited by computer resources and one's ability to specify necessary parameters. By embedding into the FDTD code alternative numerical methods that solve the aspects of the problem which are not practical, or possible, for the FDTD code to handle, power and flexibility can be added. This report investigates three such hybrid schemes. Topics include: (1) embedding a transient multiconductor/circuit-analysis code so that coupling down to the component level can be directly computed; (2) the effectiveness of using a multiconductor transmission-line code to analyze shielded multiwire cables in FDTD calculations; and (3) the effectiveness of using two-- and three-- dimensional aperture transfer functions to model narrow apertures in FDTD formulations. These topics were selected because of their immediate need in system assessments. Experimental measurements and/or alternative solution methods are used to verify the hybrid approaches. 56 figs.
In past five years, Department 1510 has developed a state-of-the-art Aerosol Dynamics Laboratory (ADL). This report documents the current instrumentation and capabilities that exist in this laboratory. The ADL was developed from a variety of sources, with a primary contribution from Department 1510's Independent Research and Development program in aerosol dynamics. Current capabilities of the ADL include: (1) generation of calibration-quality monodisperse particles with diameters between 0.005 to 100 {mu}m, (2) real-time measurement of particle size distributions for particle diameters between 0.01 and 100 {mu}m, (3) in situ, real-time measurement of particle size distributions for particle diameters between 0.3 and 100 {mu}m, and (4) real-time measurement of particle charge distributions for particle diameters between 0.01 and 1.0 {mu}m. 14 refs., 5 figs.
Analyses related to the Supplemental Environmental Impact Statement and preliminary performance assessment studies have suggested that alteration of the method of waste emplacement in the Waste Isolation Pilot Plant (WIPP) may be necessary in order to satisfy waste storage regulations. Good engineering practice also dictates consideration of changes which are useful for better containment of waste. This report presents a preliminary evaluation of various engineered modifications that might be considered. The report is based on work that has been ongoing at Sandia National Laboratories since FY88, before formation of the present Engineering Alternative Task Force by the Department of Energy WIPP Project Office. The engineered modifications under consideration are described and characterized in the first part of the report according to: the objective that would be addressed by their application; their level of complexity; and some of the presently understood limitations and uncertainties of their use. Results of studies conducted to date to examine the feasibility of some of the modification concepts are presented, with emphasis on the effects of waste supercompaction.'' 21 refs., 14 figs., 5 tabs.
When the Morton Salt Mine in Weeks Island, Louisiana was converted into a strategic Petroleum Reserve oil reservoir, massive concrete bulkheads were installed to seal the access shafts against oil or water leakage. Recent inspection of these bulkheads has raised questions about their ability to perform satisfactorily in the event of a catastrophic water leak into the mine. Calculations are reported here which examine the response of the five bulkheads to a worst-case scenario of flooding by brine from the surface into the oil reservoir below the bulkheads. These calculations show that, under conservative analysis assumptions, factors of safety under such a load for the bulkheads sealing the service shaft and the two raisebores are close to 1. The Markel incline and production shaft bulkheads exhibit safety factors in excess of 2 and 3, respectively. 10 refs., 24 figs., 3 tabs.
GREPOS is a mesh utility program that repositions or modifies the configuration of a two-dimensional or three-dimensional mesh. GREPOS can be used to change the orientation and size of a two-dimensional or three-dimensional mesh; change the material block, nodeset, and sideset IDs; or explode'' the mesh to facilitate viewing of the various parts of the model. GREPOS also updates the EXODUS Quality Assurance (QA) and information records to help track the codes and files used to generate the mesh. GREPOS reads and writes two-dimensional and three-dimensional mesh databases in the GENESIS database format; therefore, it is compatible with the preprocessing, postprocessing, and analysis codes used by the Engineering Analysis Department at Department at Sandia National Laboratories (SNL).
A seismic signal processing procedure is designed so that its performance is optimized for a specific seismic array looking for explosions at a specific teleseismic location. In this report we first describe the processing procedure, which essentially estimates beamformer signal power as a function of time in a specified frequency band. Then we calibrate the procedure for the Norwegian Regional Seismic array (NRSA) in terms of equivalent body magnitude'' (emb) level versus signal power using US Department of Interior/Geological Survey (USGS) epicenter data from documented explosions at the USSR Semipalatinsk test area in Eastern Kazakh. Finally, we test the performance of the procedure on actual NRSA data and estimate that explosions above approximately mb 4.0 at Semipalatinsk correspond with an event rate in the emb signal on the order of one to ten events per hour. We conclude that, to detect and analyze events around the clock at levels below mb 4.0, an automatic event locator must be used to process the output of the procedure described here. 8 refs., 19 figs., 1 tab.
Rush, E.E.; Chavez, J.M.; Matthews, C.W.; Bator, P.
This interim report provides results of the molten salt pump and valve loop testing, lessons learned, and recommendations based on the test results to date. The molten salt pump and valve test loop is intended to demonstrate the effectiveness of full-scale hot and cold salt pumps and valves. The pump and valve testing consists of two pumped loops, one to simulate the hot side of the receiver (565{degree}C, referred to as the hot loop) and one for the cold side (285{degree}C, referred to as the cold loop). Each loop contains a pump and six representative valves scaled for a 60-MW{sub e} commercial solar power plant using molten salt heat transport fluid. The test loop is part of the Molten Salt Subsystem/Component Test Experiment (MSS/CTE), which is being conducted to reduce the technical risk of building and operating commercial solar central receiver plants. The project, managed by Sandia National Laboratories (SNL) with Babcock and Wilcox (B W) as the prime contractor, is cost shared by DOE and six contractors. The hot loop has operated over 2400 hours in the fully automatic sequence mode. The last 500 hours have been through continuous 24-hour, 7-day operation. The hot pump operation hours simulate over 2 years of pump cycles. The cold loop has operated 12 hours in the manual mode; this is because of problems caused in the manufacturing of the pump and motor. 9 refs., 6 figs., 1 tab.
Sandia National Laboratories operates the Primary Standards Laboratory (PSL) for the Department of Energy, Albuquerque Operations Office (DOE/AL). This report summarizes metrology activities that received emphasis in the second half of 1989 and provides information pertinent to the operation of the DOE/AL system-wide Standards and Calibration Program. 7 refs.
The technology that led to very large-scale integrated circuits on silicon chips also provides a basis for new microsensors that are small, inexpensive, low power, rugged, and reliable. Two examples of microsensors Sandia is developing that take advantage of this technology are the microelectronic chemical-sensor array and the radiation-sensing field-effect transistor (RADFET). Increasingly, the technology of chemical sensing needs new microsensor concepts. Applications in this area include environmental monitoring, criminal investigations, and state-of-health monitoring, both for equipment and living things. Chemical microsensors can satisfy sensing needs in the industrial, consumer, aerospace, and defense sectors. The microelectronic chemical-sensor array (Figure 1) may address some of these applications. We have fabricated six separate chemical gas-sensing areas on the microelectronic chemical-sensor array. By using different catalytic metals on the gate areas of the diodes, we can selectively sense several gases. 14 refs., 12 figs.
The characteristics of transportation cask surface contamination and the weeping'' phenomenon are reviewed. In addition, literature that pertains to the possible impact of surface contamination on repository operations is reviewed. This report consists of commentary on and rather extensive excerpts from the published literature on cask surface contamination that may have a bearing on repository risk assessment. In addition, estimates are made of the quantity of contamination that might be present on a cask. These estimates are used to calculate the direct exposure rates to personnel located at several distances from the cask. 15 refs., 15 tabs.
Sandia National Laboratories has conducted research and development in the area of enhanced or unconventional natural gas recovery since the mid-1970's. This report is a compilation, in chronological order, of the formal documentation that has resulted from that work. Since its inception, this R D has covered five general areas, which evolved in roughly the following order: instrumentation, mineback experimentation, propellant fracturing, multiwell experiment, and geoscience. The Department of Energy's U:nconvetnional Gas Program has been the predominant sponsor ofthe work represented in this bibliography. All entries of this bibliography are reports, papers, and abstracts which are available publicly -- either in published journals or as reports available through the National Technical Information Service, US Department of Commerce, 5285 Port Royal Road, Springfield, VA 22161. The Journal of Petroleum Technology and other Society of Petroleum Engineers publications contain many of the journal papers. Sandia National Laboratories reports are the majority of the published reports. Abstracts are included only if they were published.
Preliminary results for the parametric dependences of the 2.63 and 2.65 {mu}m lines of a high-pressure xenon laser are given. The power deposition is varied from 200 to 800 W/cm{sup 3} for gas mixtures of Ar(830 Torr)/Xe(4 Torr), Ar(750 Torr)/Xe(83 Torr) and Ar(621 Torr)/He(210 Torr)/Xe(4 Torr). The 2.65 {mu}m line dominates the 2.63 {mu}m line for all gas mixtures and the ratio of the 2.63 {mu}m line intensity to that for the 2.65 {mu}m line is suppressed by the higher concentration of xenon. 13 refs., 4 figs.
This manual describes the procedures for implementing IMPACT-BRC Version 2.0. IMPACTS-BRC is a generic, radiological assessment code intended to be used by the US Nuclear Regulatory Commission (NRC) to evaluate petitions to classify specific waste streams as below regulatory concern (BRC). The code is designed to demonstrate compliance to BRC standards by modeling and calculating annual radiological impacts to the maximal individual, critical groups, and the general population as the result of transportation treatment, disposal, and post-disposal activities involving low-level radioactive waste. Impacts are calculated for multiple nuclides and pathways depending on data input and treatment and disposal options specified by the code user. The treatment and disposal options include onsite incineration, offsite incineration at municipal and hazardous waste landfills. Included within the disposal options is the ability to calculate impacts from the sorting and/or recycling of metal containers and metal and glass materials. Nuclide-specific accounting is provided to facilitate identification of the critical nuclides and pathways contributing to the impacts. Default environmental and facility parameters are developed from reference treatment/disposal sites. The user has the option to replace default parameters with site-specific parameters to provide more realistic estimation of impacts. 8 refs., 10 figs., 44 tabs.
The split cavity oscillator is a resonant cavity device which can be used to highly modulate the current of a relativistic electron beam for the purpose of generating high power microwaves. It consists of a cylindrical cavity resonator which has been divided into two identical cavities by a conducting foil whose radius is less than the inner radius of the cylinder. The gap between the foil endpoint and cylinder walls forms an annular slot which couples the cavities electromagnetically. Using a particle-in-cell code, we have performed a numerical investigation of SCO structures driven by high current, magnetized, annular, relativistic electron beams. Results are presented which illustrate the dependence of current modulation efficiency and oscillation frequency on injected beam current density. In addition, simulation results are presented for a new, double-foil SCO which indicate significantly enhanced performance in comparison to the single-foil device. 10 refs., 10 figs., 2 tabs.
The purposes of this one day meeting were to identify and to consolidate the issues associated with the performance of dimensional measurement systems as indicated by the results of the DOD Quality Assurance Council, the National Science Foundation, the Rich Walker GIDEP Alert, the B89 Standards Committee's work, IMOG Measurement Technology Subgroup discussions, NIST, and the CAM-I DITS (Dimensional Inspection Technologies Standards) Project. The expected results were a clearer definition and understanding of the problems, establishment of objectives for problem resolution, an approach to resolve the problems, and the identification of potential funding requirements and sources. 10 figs.
The Hypersonic Arbitrary-Body Aerodynamics (HABA) computer program predicts static and dynamic aerodynamic derivatives at hypersonic speeds for any vehicle geometry. It is intended to be used during conceptual design studies where fast computational speed is required. It uses the same geometry and hypersonic aerodynamic methods as the Mark IV Supersonic/Hypersonic Arbitrary-Body Program (SHABP) developed under sponsorship of the Air Force Flight Dynamics Laboratory; however, the input and output formats have been improved to make it easier to use. This program is available as part of the Department 9140 CAE software.
To assist in the repair of the Modular Integrated Video System (MIVS) printed circuit boards, a maintenance or service manual is essential. This manual provides a simplified overview of each PC board and explains the functions of each component. Setup procedures and parts lists for each board are included to minimize the task of aligning the boards and identifying replacement parts.
The Plasma Opening Switch (POS) designed for use on PBFA-2 was operated on the Blackjack 5 generator at Maxwell Laboratories in early 1988. Various switch configurations were tested, with the overall goal of understanding the point at which the switch begins to open, and improving uniformity of opening. Improved load current rate-or-rise and current transfer into high impedance loads were also goals. A baseline-design POS appears to have produced results similar to those seen in an earlier test series of this hardware on Blackjack 5 in 1986. Addition of a second-stage opening switch yielded improvements in the areas mentioned above. Analysis of current signals indicates that switch opening in all geometries was characterized by significant power flow asymmetry downstream of the POS. This report is an analysis of data from this test series.
Part 1 of this review deals with the effects of ionizing radiation on glass in the absence of hydrogen and should be consulted for background information not repeated in Part 2. This part includes information on the behavior of hydrogen in glass and how it is affected by experimental variables such as temperature, pressure, and glass composition. The reaction of hydrogen with irradiated glass is treated next, and finally the effects of ionizing radiation on hydrogen-impregnated glass are summarized. 51 refs., 1 tab.
This MIVS instruction manual provides a detailed description of all the capabilities that this system can perform. It provides step by step instruction for setting up the system parameters and the procedure for initiating surveillance. This information complements the training received prior to field operation of this system. 6 figs., 13 tabs.
The effects of ionizing radiation (e.g., beams of electrons of {gamma}-radiation) on silica and borosilicate glasses are summarized in this review article. In Part 1, irradiation in the absence of hydrogen is considered. The combined effects of hydrogen and irradiation are treated in Part 2. Descriptions and, if available, mechanisms of changes in the glass properties are discussed. Several experimental variables which may affect the outcome of an irradiation procedure are also outlined. 47 refs.
An elastic/plastic material model has been developed for use with the suite of Sandia Engineering Analysis Department finite element codes. This model describes post-yield strain hardening by a power law equation involving the equivalent plastic strain and includes a yield plateau or Lueders strain region. This combination of power law hardening and Lueders strain accurately represents the mechanical behavior of a large number of commonly used engineering materials. The material model is vectorized to take advantage of current super-computer architecture. The model shows only a modest increase in CPU time over the linear hardening material model currently in the codes. Several example problems are presented to show the accuracy and flexibility of the elastic/plastic power law hardening model. 12 refs., 10 figs., 3 tabs.
In this document, masses of the STAR-C power system and an optimized out-of-core thermionic reactor (OTR) power system versus power level are investigated. The impacts of key system parameters on system performance are also addressed. The STAR-C is mass competitive below about 15 kWe, but at higher power levels the scalability is relatively poor. An optimized OR is the least massive space nuclear power system below 25 kWe, and scales well to 50 kWe. The system parameters that have a significant impact on the scalability of the STAR-C are core thermal flux, thermionic converter efficiency, and core length to diameter ratio. The emissivity of the core surface is shown to be a relatively unimportant parameter. For an optimized OR power system, the most significant system parameter is the maximum allowable fuel temperature. It is also shown that if advanced radiation-hardened electronics are used in the satellite payload, a very large mass savings is realized. 10 refs., 23 figs., 7 tabs.
ANEOS is an in-line software package which provides thermodynamic information for shock physics codes. Solids, liquids, vapors, plasmas and phase mixtures are considered in a thermodynamically consistent and complete manner. The package is flexible and easy to use. This users manual contains input instructions, examples, and descriptions of user output. 14 refs.
Techniques for propagating data and parameter uncertainties in high-level waste (HLW) repository performance assessment models are discussed. Uncertainty analysis techniques techniques ascribe quantitative measures of reliability to model predictions. Both 10 CFR 60 and 40 CFR 191 require consideration of uncertainties, including uncertainties in data and parameters, in the performance assessment of an HLW repository system. Four categories of uncertainty analysis methods are discussed: Monte Carlo simulation, replacement models (response surface techniques), differential techniques (direct, adjoint, and Green's function technique), and geostatistical techniques (stochastic modeling using Monte Carlo simulation and spectral analysis). Advantages, disadvantages and applications of each technique are presented. Propagation of uncertainties through multiple, linked models is also discussed. Application of these techniques to sensitivity analysis is also presented. Sensitivity analyses can be useful to uncertainty studies because the number of parameters included in the uncertainty analysis can be reduced by eliminating those parameters for which the uncertainty has a minimal effect on the performance variable(s).
For improved reliability and safety, nuclear power plants are designed with redundant safety systems, many of which also have redundant trains of equipment within the system. However, the very high reliability theoretically achievable through the use of redundancy is often compromised by single events that can individually render redundant components unavailable (common cause failure (CCF) events). As evidenced by the results of probabilistic risk assessments (PRAs) and by historical experience with nuclear power plant operations, CCF events are usually major contributors to the risk posed by nuclear power plant operation. Thus, it is important that PRAs recognize the potential for CCF events and realistically account for CCF contributions to system unavailability and plant risk. Much progress has been made over the years in the area of CCF analysis, including the development of both qualitative analysis methods. Until now, however, CCF methodologies have not explicitly and systematically accounted for the impact of plant-specific defenses, such as design features and operational and maintenance policies, in place to reduce the likelihood of failure occurrences at nuclear power plants. Recognizing the importance of this issue, the NRC has funded a research effort that has focused on developing the cause-defense methodology for CCF analysis and prevention. This report presents the results of this research. Specifically, this report discusses the development of (1) procedures for identifying the potential for CCF events at individual nuclear power plants and (2) cause-defense matrices for analysis of CCF events. Also, new concepts and more precise definitions are introduced to enhance CCF terminology and interpretation of historical event data. Contains 35 refs., 8 figs., 32 tabs.
The performance and availability of the five basic identity verifiers can now meet the requirements of most physical and information security needs. However, with the lack of any evaluation standards, the independent testing of verifiers requires care with due consideration for both parts of the verifier systems; the verifier hardware and software and the user with his biometric features which is the least consistent part of the system. The method of testing and data processing must be done with care and should be reported along with reduced results.
Integrated access control portals (booths) are fast becoming a familiar part of medium-to-high security systems. Facilities wishing to expand their operations or to tighten their security, while at the same time limit or reduce their security operating expenses, find the application of portals to be a cost-effective alternative to manned entry points. With the advent of microprocessors and commuter control, portals may now be designed to operate in an automated (and in some cases, stand-alone) mode, requiring human intervention only in the event of an alarm condition. Because human intervention is minimized, a single guard can monitor the operation of several portals and thereby control multiple entry points. This report presents a description of a typical portal and its functioning and provides the information necessary to formulate a set of portal requirements. 8 figs.