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A fast solver for systems of axisymmetric ring vortices

Strickland, James H.

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.

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A balloon-borne integrating nephelometer

Brown, Gary S.

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.

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Explosive inventory program

Lewis, L.A.; Taylor, R.S.

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.

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Mass definition, mass measurement and recommendations

Braudaway, D.W.

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.

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Fractures and stresses in Bone Spring sandstones

Northrop, D.A.

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.

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Evaluation of commercially available lighting design software

Mcconnell, D.G.

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.

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Use of performance assessment in assessing compliance with the containment requirements in 40 CFR Part 191

Bonano, Evaristo J.

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.

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NIRVANA GOSIP (Government Open Systems Interconnect Profile) requirements

Wood, B.J.

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.

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Response time satisfaction in a real-time knowledge-based system

Frank, D.

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.

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Manufacturing technology: A Sandia Technology Bulletin, Volume 1, No. 1

Maydew, R.C.; Leonard, J.A.; Hey, N.S.

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.

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Detection and frequency tracking of chirping signals

Elliott, G.R.; Stearns, S.D.

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.

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Development and test case application of a waste minimization project evaluation method

Kjeldgaard, Edwin A.

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.

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NIRVANA network requirements

Wood, B.J.

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.

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Test Plan: WIPP bin-scale CH TRU waste tests

Molecke, Martin A.

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.

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Ground shock from multiple earth penetrator bursts: Effects for hexagonal weapon arrays

Kmetyk, Lubomyra N.

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.

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Argon gas analysis to predict water leakage into the W88

Gillen, Kenneth T.

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.

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The Robotic Edge Finishing Laboratory

Loucks, Clifford S.

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.

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Attenuation studies of booster-rocket propellants and their simulants

Weirick, L.J.

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.

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WhiteStar user's guide

Ezell, T.F.

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.

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Finite element error estimation and adaptivity based on projected stresses

Jung, Joseph J.

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.

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Characteristics and development report for the MC3714 thermal battery

Scharrer, Gregory L.

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.

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Analysis of Textor disruption thermal data

Russo, A.J.; Watkins, J.G.; Finken, K.H.; Dippel, K.H.; Moyer, R.A.; Gray, D.

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.

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Mechanical property mapping of the ductile cast iron MOSAIK KfK cask

Salzbrenner, R.; Crenshaw, T.B.

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.

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Using power series expansions of moduli to interpolate between release curves from dynamic tests: Technique and application

Furnish, Michael D.

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.

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Results 95851–95875 of 96,771
Results 95851–95875 of 96,771