This paper will address the purpose, scope, and approach of the Department of Energy Tiger Team Assessments. It will use the Tiger Team Assessment experience of Sandia National Laboratories at Albuquerque, New Mexico, as illustration.
The photocurrent response, photo-induced changes in hysteresis behavior, and electrooptic (birefringence) effects of sol-gel derived PZT film have been characterized as part of an effort to evaluate ferroelectric films for image storage and processing applications.
One of the common waste streams generated throughout the nuclear weapon complex is ``hardware`` originating from the nuclear weapons program. The activities associated with this hardware at Sandia National Laboratories (SNL) include design and development, environmental testing, reliability and stockpile surveillance testing, and military liaison training. SNL-designed electronic assemblies include radars, arming/fusing/firing systems, power sources, and use-control and safety systems. Waste stream characterization using process knowledge is difficult due to the age of some components and lack of design information oriented towards hazardous constituent identification. Chemical analysis methods such as the Toxicity Characteristic Leaching Procedure (TCLP) are complicated by the inhomogeneous character of these components and the fact that many assemblies have aluminum or stainless steel cases, with the electronics encapsulated in a foam or epoxy matrix. In addition, some components may contain explosives, radioactive materials, toxic substances (PCBs, asbestos), and other regulated or personnel hazards which must be identified prior to handling and disposal. In spite of the above difficulties, we have succeeded in characterizing a limited number of weapon components using a combination of process knowledge and chemical analysis. For these components, we have shown that if the material is regulated as RCRA hazardous waste, it is because the waste exhibits one or more hazardous characteristics; primarily reactivity and/or toxicity (Pb, Cd).
A brief discussion of the following topics is given in this report: Liquid Metal Divertors; Lithium Droplet Beam Divertor; Preferential Pumping of Helium; Reduced Erosion with Cu-Li, W-Li, etc.; Reduction of Erosion by Thermionic Emission; Reduced Erosion in Boronized Graphites; Proposal for Materials Experiments in TRIAM; Carbon-SiC for Plasma Facing Components; Helium Pumping with Palladium; Large Area Pump Limiter; Techniques for Enhanced Heat Removal; New Outlook on Gaseous Divertors; Gaseous Divertor Simulations; Impurity Seeding to Control ITER Particle and Heat Loads; Gaseous Divertor Experiments; Electrical Biasing to Control SOL Particle Fluxes; Biased Limiter in TEXTOR and Biased Divertor in PBX-M; Particle and Heat Flux Control Using Ponderomotive Forces; Helium Exhaust Using ICRF; Ergodic Magnetic Limiter Experiments in JFT-2M; and Helium Exhaust Using Fishbones.
The effects of argon addition to the vacuum arc remelting (VAR) process were studied in both laboratory and industrial experiments while remelting Alloy 718. The results demonstrate that argon can be added to an industrial VAR furnace to relatively high partial pressures without decreasing the melt rate, drip-short frequency, or constricting the arc plasma to a local region of the electrode surface. Laboratory experiments illustrate that this result is dependent on electrode chemistry, possibly related to magnesium content.
Melt pool shape in VAR is controlled by fluid flow, which is governed by the balance between two opposing flow fields. At low melt currents, flow is dominated by thermal buoyancy. In these instances, metal is swept radially outward on the pool surface, resulting in relatively shallow melt pools but increased heat transfer to the crucible at the melt pool surface. At high melt currents, flow is primarily driven by magento-hydrodynamic forces. In these cases, the surface flow is radially inward and downward, resulting in a constricted arc, the pool depth and relative heat transfer to the crucible are intermediate, even though the melt rate is significantly lower than either diffuse arc condition. Constricted arc conditions also result in erratic heat transfer behavior and non-uniformities in pool shape.
This report describes the Training and Qualification Program at the Simulation Technology Laboratory (STL). The main facility at STL is Hermes III, a twenty megavolt accelerator which is used to test military hardware for vulnerability to gamma-rays. The facility is operated and maintained by a staff of twenty engineers and technicians. This program is designed to ensure that these personnel are adequately trained and qualified to perform their jobs in a safe and efficient manner. Copies of actual documents used in the program are included in appendices. This program meets all the requirements for training and qualification in the DOE Orders on Conduct of Operations and Quality Assurance, and may be useful to other organizations desiring to come into compliance with these orders.
Division 2473 has characterized the performance of three types of focusing lenses used for CO{sub 2} laser beam welding. Specifically, we evaluated the plano-convex, positive meniscus, and aspheric lenses with focal lengths ranging from 1.25 to 5.0 inches. The measured responses were the resultant weld depth and width of bead-on-plate welds made using a range of focus positions. The welding parameters were 185 to 700 watts continuous wave beam power and 30 inches per minute travel speed. The results of this study quantified the weld profile dimensions as a function of lens type and focal length, beam power, depth of focus, and verified the coincidence of maximum weld depth and width.
The WC-1 and WC-3 experiments were conducted using a dry, 1:10 linear scale model of the Zion reactor cavity to obtain baseline data for comparison to future experiments that will have water in the cavity. WC-1 and WC-3 were performed with similar initial conditions except for the exit hole between the melt generator and the scaled model of the reactor cavity. For both experiments the molten core debris was simulated by a thermitically generated melt formed from 50 kg of iron oxide/aluminum/chromium powders. After the thermite was ignited in WC-1, the melt was forcibly ejected by 374 moles of slightly superheated steam at an initial driving pressure of 4.6 MPa through an exit hole with an actual diameter of 4.14 cm into the scaled model of the reactor cavity. In WC-3, the molten thermite was ejected by 300 moles of slightly superheated steam at an initial driving pressure of 3.8 MPa through an exit hole with an actual diameter of 10.1 cm into the scaled model of the reactor cavity. Because of the larger exit hole diameter, WC-3 had a shorter blowdown time than WC-1, 0.8`s compared to 3.0`s. WC-3 also had a higher debris velocity than WC-1, 54 m/s compared to 17.5 m/s. Posttest sieve analysis of debris recovered from the Surtsey vessel gave identical results in WC-1 and WC-3 for the sieve mass median particle diameter, i.e. 1.45 mm. The total mass ejected into the Surtsey vessel in WC-3 was 45.0 kg compared to 47.9 kg in WC-1. The peak pressure increase in Surtsey due to the high-pressure melt ejection (HPME) was 0.275 MPa in WC-3 and 0.272 in WC-1. Steam/metal reactions produced 181 moles of of hydrogen in WC-3 and 145 moles of hydrogen in WC-1.
Transport models used for performance assessment of the Waste Isolation Pilot Plant (WIPP) in the event of human intrusion into the repository currently rely on the K{sub d} linear sorption isotherm model to predict rates of radionuclide migration. The vast majority of K{sub d} data was measured in static (batch) experiment on powdered substrate; most data specific to the Culebra dolomite were gathered in this way for five radioelements of concern using up to four different water compositions. This report summarizes the available data, examines inconsistencies between these data and the assumptions of the K{sub d} model, and discusses potential difficulties in using existing sorption data for predictive modeling of radionuclide retardation through adsorption modeling are presented as an alternative to the K{sub d} model.
ITS is a powerful and user-friendly software package permitting state-of-the-art Monte Carlo solution of linear time-independent coupled electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Our goal has been to simultaneously maximize operational simplicity and physical accuracy. Through a machine-portable utility that emulates the basic features of the CDC UPDATE processor, the user selects on of eight codes for running on a machine of one of at least four major vendors. The ease with which this utility is applied combines with an input scheme based on order-independent descriptive keywords that makes maximum use of defaults and internal error checking to provide experimentalists and theorists alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Physical rigor is maximized by employing the best available cross sections and sampling distributions, and the most complete physical model for describing the production and transport of the electron/photon cascade from 1.0 GeV down to 1.0 keV. Feasibility of construction permits the more sophisticated user to tailor the codes to specific applications and to extend the capabilities of the codes to more complex applications through simple update procedures. Version 3.0, the latest version of ITS, contains major improvements to the physical model, additional variance reduction via both internal restructuring and new user options, and expanded input/output capabilities.
A new algorithm for the treatment of sliding interfaces between solids with or without friction in an Eulerian wavecode is described. The algorithm has been implemented in the two-dimensional version of the CTH code. The code was used to simulate penetration and perforation of aluminum plates by rigid, conical-nosed tungsten projectiles. Comparison with experimental data is provided.
The first phase of a program to study the resistance of exclusion region barriers to ductile failure when subjected to accident-type, quasi-static extreme mechanical loads has been completed. This first phase consisted to qualification of the analytical tools used to study these types of structural deformations and the development of appropriate criteria to predict ductile failure. A series of tests were performed on hydroformed half-cylinder barrier mock-ups. The qualification activity was considered a success based upon the comparison of the deformations and loads measured during the testing to the response of these structures computed by the finite element modeling. This successful completion of the first phase allows the second phase program to proceed. 12 refs.
We have measured, by {sup 1}H and {sup 13}C nuclear magnetic resonance (NMR), the percent deuteration, the tacticity and the purity of several polymers and one solvent used in the preparation of microcellular foams. The percent deuteration was measured for polystyrene, polyacrylonitrile and polyethylene. The tacticities of polystyrene and polyacrylonitrile were determined. The purity and degradation products of polyacrylonitrile and maleic anhydride were examined. This report documents the experimental procedures and results of these measurements.
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 1991 and provides information pertinent to the operation of the DOE/AL system-wide Standards and Calibration Program.
The effects of cavern spacing and operating pressure on surface subsidence and cavern storage losses were evaluated using the finite- element method. The base case for the two sensitivity studies was a typical SPR cavern. The predicted responses of the base case and those from the pressurization study compared quite closely to measured surface subsidence and oil pressurization rates. This provided credibility for the analyses and constitutive models used. Subsidence and cavern storage losses were found to be strongly influenced by cavern spacing and pressurization. The relationship between subsidence volume and losses in storage volume varied as cavern spacing and operating pressure deviated from the base case. However, for a typical SPR cavern subsidence volume is proportional to storage loss and when expressed in ft., subsidence is equal to the percentage of storage loss.
The goal of the wet cavity (WC) test series was to investigate the effect of water in a reactor cavity on direct containment heating (DCH). The WC-1 experiment was performed with a dry cavity to obtain baseline data for comparison to the WC-2 experiment. WC-2 was conducted with water 3 cm deep (11.76 kg) in a 1:10 linear scale model of the Zion reactor cavity. The initial conditions for the experiments were similar. For both experiments the molten core debris was simulated by a thermitically generated melt formed from 50 kg of iron oxide/aluminum/chromium powders. After the charge was ignited, the debris was melted by the chemical reaction and was forcibly ejected through a nominal 3.5 cm hole into the scaled reactor cavity by superheated steam at an initial driving pressure of 4.58 MPa. The peak pressure increase in the containment due to the high-pressure melt ejection (HPME) was 0.272 MPa in WC-1 and 0.286 MPa in WC-2. The total amount of hydrogen generated in the experiments was 145 moles of H{sub 2} in WC-1 and 179 moles of H{sub 2} in WC-2. The total mass of debris ejected into the containment was identical for both experiments. These results suggest that water in the cavity slightly enhanced DCH.
Laboratory simulation of the approach of a radar fuze towards a target is an important factor in our ability to accurately measure the radar`s performance. This simulation is achieved, in part, by dynamically delaying and attenuating the radar`s transmitted pulse and sending the result back to the radar`s receiver. Historically, the device used to perform the dynamic delay has been a limiting factor in the evaluation of a radar`s performance and characteristics. A new device has been proposed that appears to have more capability than previous dynamic delay devices. This device is the digital RF memory. This report presents the results of an analysis of a digital RF memory used in a signal-delay application. 2 refs.
This report describes research and development related to Mo-based catalysts supported on hydrous metal oxide in exchangers for use in direct coal liquefaction processes. A group of NiMo catalysts were prepared on different hydrous titanium oxide (HTO) supports to serve as baseline materials for use in determining the effects of altering process parameters on the physical and catalytic properties of NiMoHTO catalysts. The baseline group included catalysts which had hydrogenation activities up to 40% higher than the best commercial NiMo/Al{sub 2}O{sub 3} catalysts used in coal liquefaction pilot plant studies on a weight of catalyst basis while containing 25% less active metal. The results of high resolution electron microscopy (HREM) studies addressing the effects of processing parameters on microstructure are also presented. NiMoHTO catalysts were included in a group of some 30 commercial and experimental catalysts tested at Amoco Oil Co. to determine applicability for upgrading coal resids. The performance of NiMoHTO catalysts in these tests was better than or comparable to the best commercial catalysts available for this application. The initial work with thin-film NiMoHTO catalysts supported on commercial silica gel spheres is presented. Second generation thin-film catalysts containing about 1% Mo have hydrogenation activities of about 75% of those of extruded commercial NiMo/Al{sub 2}O{sub 3} catalysts containing 10--13% Mo and up to 50% of the hydrodesulfurization activity of the commercial catalysts. The use of thin-film HTO technology, which allows for preparation of NiMoHTO catalysts on virtually any substrate lowers catalyst cost by reducing the amount of Ti required and provides engineering forms of HMO materials without development work needed to convert bulk HTO materials into usable engineering forms. Work done with NiMo catalysts supported on hydrous zirconium oxide (HZO) is also presented.
The third experiment of the Integral Effects Test (IET-3) series was conducted to investigate the effects of high pressure melt ejection (HPME) on direct containment heating (DCH). A 1:10 linear scale model of the Zion reactor pressure vessel (RPV), cavity, instrument tunnel, and subcompartment structures were constructed in the Surtsey Test Facility at Sandia National Laboratories (SNL). The RPV was modeled with a melt generator that consisted of a steel pressure barrier, a cast MgO crucible, and a thin steel inner liner. The melt generator/crucible had a semi-hemispherical bottom head containing a graphite limitor plate with a 3.5 cm exit hole to simulate the ablated hole in the RPV bottom head that would be formed by tube ejection in a severe nuclear power plant (NPP) accident. The reactor cavity model contained 3.48 kg of water with a depth of 0.9 cm that correspond to condensate levels in the Zion plant. A steam driven iron oxide/aluminum/chromium thermite was used to simulate HPME. IET-3 replicated the first experiment in the IET series (IET-1) except the Surtsey vessel contained 0.09 MPa air and 0.1 MPa nitrogen. No steam explosions occurred in the cavity in IET-3 experiment. The cavity pressure measurements showed that rapid vaporization of water occurred in the cavity at about the same time as the steam explosion in IET-1. However, the oxygen in the Surtsey vessel in IET-3 resulted in a vigorous hydrogen burn, which caused a significant increase in the peak pressure, 246 kPa compared to 98 kPa in the IET-1 test. The total debris mass ejected into the Surtsey vessel in IET-3 was 34.3 kg, and gas grab sample analysis indicated that 223 moles of hydrogen were produced by steam/metal reactions. About 186 moles of hydrogen burned and 37 moles remained unreacted.
This document presents planned actions, and their associated costs, for addressing the findings in the Environmental, Safety and Health Tiger Team Assessment of the Sandia National Laboratories, Albuquerque, May 1991, hereafter called the Assessment. This Final Action Plan should be read in conjunction with the Assessment to ensure full understanding of the findings addressed herein. The Assessment presented 353 findings in four general categories: (1)Environmental (82 findings); (2) Safety and Health (243 findings); (3) Management and Organization (18 findings); and (4) Self-Assessment (10 findings). Additionally, 436 noncompliance items with Occupational Safety and Health Administration (OSHA) standards were addressed during and immediately after the Tiger Team visit.
This paper addresses problems of synchronization and coordination in the context of faulty shared memory. We present algorithms for the consensus problem, and for reliable shared memory objects, from collections of read/write registers, 2-processor binary test-and-set objects, and read-modify-write registers, some of which may be faulty.
A computer program has been developed to reduce and analyze data from a standardized piezoelectric polymer (PVDF) shock-wave stress rate gauge. The program is menu driven with versatile graphic capabilities, input/output file options, hard copy options, and unique data processing capabilities. This program was designed to analyze digital current-mode'' data recorded from a Bauer PVDF stress-rate gauge and reduce it to a stress-versus-time record. The program was also designed to combine two simulanteously recorded data channels.
The purpose of the molten-salt pump and valve loop test is to demonstrate the performance, reliability, and service life of full-scale hot- and cold-salt pumps and valves for use in commercial central receiver solar power plants. This test was in operation at Sandia National Laboratories National Solar Thermal Test Facility from January 1988 to September 1990. The test hardware consists of two pumped loops; the hot-salt loop'' to simulate the piping and components on the hot (565{degrees}C) side of the receiver and the cold-salt loop'' to simulate piping and components on the receiver's cold (285{degrees}C) side. Each loop contains a pump and five valves sized to be representative of a conceptual 60-MW{sub e} commercial solar power plant design. The hot-salt loop accumulated over 6700 hours of operation and the cold-salt loop over 2500 hours during the test period. This project has demonstrated the performance and reliability required for commercial-scale molten-salt pumps and valves.