Material and processing issues for the monolithic integration of microelectronics with surface-micromachined polysilicon sensors and actuators (open access)

Material and processing issues for the monolithic integration of microelectronics with surface-micromachined polysilicon sensors and actuators

The monolithic integration of micromechanical devices with their controlling electronics offers potential increases in performance as well as decreases in cost for these devices. Analog Devices has demonstrated the commercial viability of this integration by interleaving the micromechanical fabrication steps of an accelerometer with the microelectronic fabrication steps of its controlling electronics. Sandia`s Microelectronics Development Laboratory has integrated the micromechanical and microelectronic processing sequences in a segregated fashion. In this CMOS-first, micromechanics-last approach, conventional aluminum metallization is replaced by tungsten metallization to allow CMOS to withstand subsequent high-temperature processing during the micromechanical fabrication. This approach is a further development of an approach originally developed at UC Berkeley. Specifically, the issues of yield, repeatability, and uniformity of the tungsten/CMOS approach are addressed. Also, material issues related to the development of high-temperature diffusion barriers, adhesion layers, and low-stress films are discussed. Processing and material issues associated with alternative approaches to this integration such as micromechanics- first, CMOS-last or the interleaved process are also discussed.
Date: August 1, 1995
Creator: Smith, J.H.; Montague, S. & Sniegowski, J.J.
Object Type: Article
System: The UNT Digital Library
Multidimensional DDT modeling of energetic materials (open access)

Multidimensional DDT modeling of energetic materials

A nonequilibrium continuum mixture model has been incorporated into the CTH shock physics code to describe deflagration-to-detonation transition in granular energetic materials. This approach treats multiple thermodynamic and mechanics fields including the effects of relative material motion, rate-dependent compaction and interphase exchange of mass, momentum and energy. A finite volume description is formulated and internal state variables are solved using an operator-splitting method. Numerical simulations of low-velocity impact on a weakly-confined porous propellant bed are presented which display lateral wall release leading to curved compaction and reaction wave behavior.
Date: August 1, 1995
Creator: Baer, M. R.; Hertel, E. S. & Bell, R. L.
Object Type: Article
System: The UNT Digital Library
Automatic history matching of geothermal field performance (open access)

Automatic history matching of geothermal field performance

We have developed inverse modeling capabilities for the multiphase multicomponent numerical simulator TOUGH2 to facilitate automatic history matching, and parameter estimation based on data obtained during exploitation of Geothermal fields. The ITOUGH2 code allows one to estimate TOUGH2 input parameters based on any type of observation for which a corresponding TOUGH2 output can be calculated. Furthermore, a detailed residual and error analysis is performed, and the uncertainty of model predictions can be evaluated. This paper focuses on the solution of the inverse; problem, i.e. the determination of model-related parameters by automatically calibrating a conceptual model of the Geothermal system against data obtained during field operation. We first describe the modeling, approach used to simulate fluid and heat flow in fractured-porous media. The inverse problem is then formulated, followed by a brief discussion of the optimization algorithm. A sample problem is given to demonstrate the application of the method to Geothermal reservoir data.
Date: August 1, 1995
Creator: Finsterle, S. & Pruess, K>
Object Type: Article
System: The UNT Digital Library
Global shielding analysis for the three-element core advanced neutron source reactor under normal operating conditions (open access)

Global shielding analysis for the three-element core advanced neutron source reactor under normal operating conditions

Two-dimensional discrete ordinates radiation transport calculations were performed for a model of the three-element core Advanced Neutron Source reactor design under normal operating conditions. The core consists of two concentric upper elements and a lower element radially centered in the annulus between the upper elements. The initial radiation transport calculations were performed with the DORT two-dimensional discrete ordinates radiation transport code using the 39-neutron-group/44-gamma-ray-group ANSL-V cross-section library, an S{sub 6} quadrature, and a P{sub 1} Legendre polynomial expansion of the cross sections to determine the fission neutron source distribution in the core fuel elements. These calculations were limited to neutron groups only. The final radiation transport calculations, also performed with DORT using the 39-neutron-group/44-gamma-ray-group ANSL-V cross-section library, an S{sub l0} quadrature, and a P{sub 3} Legendre polynomial expansion of the cross sections, produced neutron and gamma-ray fluxes over the full extent of the geometry model. Responses (or activities) at various locations in the model were then obtained by folding the appropriate response functions with the fluxes at those locations. Some comparisons were made with VENTURE-calculated (diffusion theory) 20-group neutron fluxes that were summed into four broad groups. Tne results were in reasonably good agreement when the effects of photoneutrons were …
Date: August 1, 1995
Creator: Slater, C. O. & Bucholz, J. A.
Object Type: Report
System: The UNT Digital Library
Synthesis, characterization, phase diagrams and superconducting and normal state magnetic properties of La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (0 {le} x {le} 0.08) and electrochemically oxidized La{sub 2{minus}x}Sr{sub x}CuO{sub 4+{delta}} (0 {le} x {le} 0.33, 0 {le} {delta} {le} 0.12) (open access)

Synthesis, characterization, phase diagrams and superconducting and normal state magnetic properties of La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (0 {le} x {le} 0.08) and electrochemically oxidized La{sub 2{minus}x}Sr{sub x}CuO{sub 4+{delta}} (0 {le} x {le} 0.33, 0 {le} {delta} {le} 0.12)

La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (0 {le} x {le} 0.15) can all be intercalated with oxygen by a novel electrochemical oxidation method. Bulk superconductivity is found with an onset {Tc} {approx} 40 K for the whole range 0.01 {le} x {le} 0.15; for x = 0.25 and 0.33, the electrochemical oxidation did not improve the superconducting properties. The magnetic susceptibility {chi}(T = 50--320 K) data for La{sub 2}CuO{sub 4.11} and La{sub 1.92}Sr{sub 0.08}CuO{sub 4.07} are nearly identical with those of conventionally prepared La{sub 1.85}Sr{sub 0.15}CuO{sub 4}, indicating that the hole doping level (p) in the CuO{sub 2} planes of the three compounds is nearly the same. Combined thermogravimetric analysis and iodometric titration experiments indicate that part of the intercalated oxygen has a formal valence close to {minus}1. The maximum doped-hole concentration in the CuO{sub 2} planes that can be achieved from combined Sr-doping and electrochemical oxygen doping for 0 {le} x {le} 0.15 is p {approx} 0.16 holes/formula unit. Oxygen can also intercalate into single crystal La{sub 2}CuO{sub 4} through a slow electrochemical oxidation process. The required low current and long time for the charging process reflects that the oxygen intercalation for a single crystal is limited by its small specific …
Date: August 1, 1993
Creator: Chou, F.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
1993 RCRA Part B permit renewal application, Savannah River Site: Volume 10, Consolidated Incineration Facility, Section C, Revision 1 (open access)

1993 RCRA Part B permit renewal application, Savannah River Site: Volume 10, Consolidated Incineration Facility, Section C, Revision 1

This section describes the chemical and physical nature of the RCRA regulated hazardous wastes to be handled, stored, and incinerated at the Consolidated Incineration Facility (CIF) at the Savannah River Site. It is in accordance with requirements of South Carolina Hazardous Waste Management Regulations R.61-79.264.13(a) and(b), and 270.14(b)(2). This application is for permit to store and teat these hazardous wastes as required for the operation of CIF. The permit is to cover the storage of hazardous waste in containers and of waste in six hazardous waste storage tanks. Treatment processes include incineration, solidification of ash, and neutralization of scrubber blowdown.
Date: August 1, 1993
Creator: Molen, G.
Object Type: Report
System: The UNT Digital Library
Procyon: 18-MJ, 2-{mu}s pulsed power system (open access)

Procyon: 18-MJ, 2-{mu}s pulsed power system

The Procyon high explosive pulsed power (HEPP) system was designed to drive plasma z-pinch experiments that produce Megajoule soft x-ray pulses when the plasma stagnates on axis. In the proceedings of the Ninth IEEE Pulsed Power Conference, we published results from system development tests. At this time, we have fielded seven tests in which the focus was on either vacuum switching or load physics. Four of the tests concentrated on the performance of a Plasma Flow Switch (PFS) which employed a 1/r mass distribution in the PFS barrel. Of the four tests, two had dummy loads and one had an implosion load. In addition, one of the tests broke down near the vacuum dielectric interface, and the result demonstrated what Procyon could deliver to an 18 nH load. We will summarize PFS results and the 18 nH test which is pertinent to upcoming solid/liquid liner experiments. On our other three tests, we eliminated the PFS switching and powered the z-pinch directly with the HEPP system. From the best of these direct drive tests we obtained 1.5 MJ of radiation in a 250 ns pulse, our best radiation pulse to date. We will also summarize direct drive test results. More details …
Date: August 1, 1995
Creator: Goforth, J.H.; Anderson, B.G. & Anderson, W.E.
Object Type: Article
System: The UNT Digital Library
Vapor pressures and heats of vaporization of primary coal tars. Quarterly technical progress report, 1 January 1995--31 March 1995 (open access)

Vapor pressures and heats of vaporization of primary coal tars. Quarterly technical progress report, 1 January 1995--31 March 1995

The vapor pressure correlations that exist at present for coal tars are very crude and they are not considered reliable to even an order of magnitude when applied to tars. Sophisticated general correlative approaches are slowly being developed, based upon group contribution methods, or based upon some key functional features of the molecules. These are as yet difficult to apply to coal tars. The detailed group contribution methods, in which fairly precise structural information is needed, do not lend themselves well for application to very complex, poorly characterized coal tars. The methods based upon more global types of characterizations have not yet dealt much with the question of oxygenated functional groups. In short, only very limited correlations exist, and these are not considered reliable to even an order of magnitude when applied to tars. The present project seeks to address this important gap in the near term by direct measurement of vapor pressures of coal tar fractions, by application of well-established techniques and modifications thereof. The principal objectives of the program are to: (1) obtain data on the vapor pressures and heats of vaporization of tars from a range of ranks of coal, (2) develop correlations based on a minimum …
Date: August 1, 1995
Creator: Suuberg, E.M.; Oja, V. & Lilly, W.D.
Object Type: Report
System: The UNT Digital Library
Why in situ, real-time characterization of thin film growth processes? (open access)

Why in situ, real-time characterization of thin film growth processes?

Since thin-film growth occurs at the surface, the analytical methods should be highly surface-specific. although subsurface diffusion and chemical processes also affect film properties. Sampling depth and ambient-gas is compatibility are key factors which must be considered when choosing in situ probes of thin-film growth phenomena. In most cases, the sampling depth depends on the mean range of the exit species (ion, photon, or electron) in the sample. The techniques that are discussed in this issue of the MRS Bulletin (1) have been chosen because they may be used for in situ, real-time analysis of film-growth phenomena in vacuum and in the presence of ambient gases resulting either from the deposition process or as a requirement for the production of the desired chemical phase. A second criterion for inclusion is that the instrumentation be sufficiently compact and inexpensive to permit use as a dedicated tool in a thin-film deposition system.
Date: August 1, 1995
Creator: Auciello, O. & Krauss, A. R.
Object Type: Report
System: The UNT Digital Library
Advanced Blade Manufacturing Project - Final Report (open access)

Advanced Blade Manufacturing Project - Final Report

The original scope of the project was to research improvements to the processes and materials used in the manufacture of wood-epoxy blades, conduct tests to qualify any new material or processes for use in blade design and subsequently build and test six blades using the improved processes and materials. In particular, ABM was interested in reducing blade cost and improving quality. In addition, ABM needed to find a replacement material for the mature Douglas fir used in the manufacturing process. The use of mature Douglas fir is commercially unacceptable because of its limited supply and environmental concerns associated with the use of mature timber. Unfortunately, the bankruptcy of FloWind in June 1997 and a dramatic reduction in AWT sales made it impossible for ABM to complete the full scope of work. However, sufficient research and testing were completed to identify several promising changes in the blade manufacturing process and develop a preliminary design incorporating these changes.
Date: August 1, 1999
Creator: POORE, ROBERT Z.
Object Type: Report
System: The UNT Digital Library
DSI3D-RCS test case manual (open access)

DSI3D-RCS test case manual

The DSI3D-RCS code is designed to numerically evaluate radar cross sections on complex objects by solving Maxwell`s curl equations in the time-domain and in three space dimensions. The code has been designed to run on the new parallel processing computers as well as on conventional serial computers. The DSI3D-RCS code has been used to solve the following problems: (1) wedge cylinder--thin flat metal plate; (2) wedge cylinder with plate extension--thin flat metal plate; (3) plate with half cylinder extension--thin flat metal plate; (4) rectangular plate (business card)--thin flat metal plate; (5) wedge cylinder with gap--thin flat metal plate; (6) NASA Almond; (7) wavelength circular cavity. In order to generate each of the angle sweeps, it was necessary to run DSI3D once for each data point on the graphs. This is because these are backscatter calculations, and the incident pulse comes from a different direction as the angle {phi} is changed.
Date: August 1, 1995
Creator: Madsen, N.; Steich, D.; Cook, G. & Eme, B.
Object Type: Report
System: The UNT Digital Library
Impact evaluation of a major residential efficiency program: The importance of market transformation (open access)

Impact evaluation of a major residential efficiency program: The importance of market transformation

In the Pacific Northwest, about 40% of new electrically heated homes are HUD-code manufactured homes (commonly called {open_quotes}mobile homes{close_quotes}). The U.S. Department of Housing and Urban Development (HUD) sets national energy-efficiency construction standards for manufactured homes that preempt them from local building codes. Until October 1994, a relatively low efficiency requirement established in 1976 by HUD was in place for manufactured homes. The Bonneville Power Administration (Bonneville) is required to acquire cost-effective energy efficiency to meet the electricity needs of the Pacific Northwest. Because electrically heated manufactured homes are so common and are relatively inefficient, Bonneville, utilities, state energy offices, and others have conducted a series of programs since 1982 to upgrade their efficiency (1). Because of the preemptive national code, these programs have all been voluntary for manufactured homes. Bonneville and the regional utilities and manufacturers created the Manufactured Housing Acquisition Program (MAP) in April 1992 after conducting projects for ten years to determine the cost of manufactured home energy-efficiency upgrades, predict and measure energy consumption, and establish a regional partnership. The program was phased in over several months; since October 1992, all electrically heated manufactured homes produced in the region have been built to MAP specifications.
Date: August 1, 1995
Creator: Lee, A. D.; Taylor, Z. T. & Sandahl, L. J.
Object Type: Article
System: The UNT Digital Library
Information/records management-defensible budgets for the 21st century (open access)

Information/records management-defensible budgets for the 21st century

This paper provides to the Nuclear Information and Records Management Association (NIRMA) members the skills, knowledge, and information needed to develop performance-based cost estimating. It includes a detailed basis of estimates to represent a work breakdown structure that is technically complete, fully documented, defensible to various external reviews, and validatable.
Date: August 1, 1995
Creator: DiLiberto, A.J. & Whittet, L.A.
Object Type: Article
System: The UNT Digital Library
Micromachined silicon seismic transducers (open access)

Micromachined silicon seismic transducers

Batch-fabricated silicon seismic transducers could revolutionize the discipline of CTBT monitoring by providing inexpensive, easily depolyable sensor arrays. Although our goal is to fabricate seismic sensors that provide the same performance level as the current state-of-the-art ``macro`` systems, if necessary one could deploy a larger number of these small sensors at closer proximity to the location being monitored in order to compensate for lower performance. We have chosen a modified pendulum design and are manufacturing prototypes in two different silicon micromachining fabrication technologies. The first set of prototypes, fabricated in our advanced surface- micromachining technology, are currently being packaged for testing in servo circuits -- we anticipate that these devices, which have masses in the 1--10 {mu}g range, will resolve sub-mG signals. Concurrently, we are developing a novel ``mold`` micromachining technology that promises to make proof masses in the 1--10 mg range possible -- our calculations indicate that devices made in this new technology will resolve down to at least sub-{mu}G signals, and may even approach to 10{sup {minus}10} G/{radical}Hz acceleration levels found in the low-earth-noise model.
Date: August 1, 1995
Creator: Barron, C. C.; Fleming, J. G.; Sniegowski, J. J.; Armour, D. L. & Fleming, R. P.
Object Type: Article
System: The UNT Digital Library
A cost-effective adverse-weather precision guidance system (open access)

A cost-effective adverse-weather precision guidance system

This SAND report documents the results of an LDRD project undertaken to study the accuracy of terrain-aided navigation coupled with highly accurate topographic maps. A revolutionary new mapping technology, interferometric synthetic aperture radar (IFSAR), has the ability to make terrain maps of extremely high accuracy and spatial resolution, more than an order of magnitude better than currently available DMA map products. Using a laser altimeter and the Sandia Labs Twin Otter Radar Testbed, fix accuracies of less than 3 meters CEP were obtained over urban and natural terrain regions.
Date: August 1, 1995
Creator: Fellerhoff, R. & Burgett, S.
Object Type: Report
System: The UNT Digital Library
In-situ property measurements on laser-drawn strands of SL 5170 epoxy and SL 5149 acrylate (open access)

In-situ property measurements on laser-drawn strands of SL 5170 epoxy and SL 5149 acrylate

Material behavior plays a significant role in the mechanics leading to internal stresses and, potentially, to distortion (curling) of parts as they are built by stereolithography processes that utilize photocuring resins. A study is underway to generate material properties that can be used to develop phenomenological material models of epoxy and acrylate resins. Strand tests are performed in situ in a 3D System`s SLA-250 machine; strands are drawn by either single or multiple exposures of the resin to a laser beam. Linear shrinkage, cross-sectional areas, cure shrinkage forces and stress-strain data are presented. Also, the curl in cantilever beam specimens, built with different draw patterns, are compared.
Date: August 1, 1995
Creator: Guess, T.R. & Chambers, R.S.
Object Type: Article
System: The UNT Digital Library
Magnetic confinement experiment. I: Tokamaks (open access)

Magnetic confinement experiment. I: Tokamaks

Reports were presented at this conference of important advances in all the key areas of experimental tokamak physics: Core Plasma Physics, Divertor and Edge Physics, Heating and Current Drive, and Tokamak Concept Optimization. In the area of Core Plasma Physics, the biggest news was certainly the production of 9.2 MW of fusion power in the Tokamak Fusion Test Reactor, and the observation of unexpectedly favorable performance in DT plasmas. There were also very important advances in the performance of ELM-free H- (and VH-) mode plasmas and in quasi-steady-state ELM`y operation in JT-60U, JET, and DIII-D. In all three devices ELM-free H-modes achieved nT{tau}`s {approximately} 2.5x greater than ELM`ing H-modes, but had not been sustained in quasi-steady-state. Important progress has been made on the understanding of the physical mechanism of the H-mode in DIII-D, and on the operating range in density for the H-mode in Compass and other devices.
Date: August 1, 1995
Creator: Goldston, R.J.
Object Type: Report
System: The UNT Digital Library
Westinghouse Reactor Protection System Unavailability, 1984-1995 (open access)

Westinghouse Reactor Protection System Unavailability, 1984-1995

An analysis was performed of the safety-related performance of the reactor protection system (RPS) at U.S. Westinghouse commercial reactors during the period 1984 through 1995. RPS operational data were collected from the Nuclear Plant Reliability Data System and Licensee Event Reports. A risk-based analysis was performed on the data to estimate the observed unavailability of the RPS, based on a fault tree model of the system. Results were compared with existing unavailability estimates from Individual Plant Examinations and other reports.
Date: August 1, 1999
Creator: Gentillon, C. D.; Marksberry, D.; Rasmuson, D.; Calley, M. B.; Eide, S. A. & Wierman, T.
Object Type: Article
System: The UNT Digital Library
The derivation of material properties from measurements of radiation induced stress-time histories (open access)

The derivation of material properties from measurements of radiation induced stress-time histories

Material response experiments using the SATURN soft x-ray source in conjunction with hydrocode modelling have been used to determine equation-of-state parameters for aluminum. In these experiments, stresswaves in irradiated targets have been measured using both quartz and PVDF piezoelectric stress gauges for a wide range of incident fluences. The induced stress profiles are sensitive functions of. (1) the deposition profiles in the target material, (2) the temporal history of the radiation source, and (3) the target material-properties. Analysis of the experimental data has shown that observed changes in the shape of the induced stresswave as fluence is varied can be directly correlated to phase transitions. The unique combination of x-ray energy and irradiation time allow phenomena important for determining equation-of-state parameters to be studied separately. By temporally separating the development of thermomechanically induced stress from stress induced by material vaporization a very sensitive measurement of vaporization energy is possible.
Date: August 1, 1995
Creator: Davies, F. W.; Reeder, D. L.; Johnson, D. E. & Lee, L. M.
Object Type: Article
System: The UNT Digital Library
Design and performance of a soft X-ray interferometer for ultra-high resolution Fourier transform spectroscopy (open access)

Design and performance of a soft X-ray interferometer for ultra-high resolution Fourier transform spectroscopy

A Fourier Transform Soft X-ray spectrometer (FT-SX) has been designed and is under construction for the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory as a branch of beamline 9.3.2. The spectrometer is a novel soft x-ray interferometer designed for ultra-high resolution (theoretical resolving power E/{delta}E{approx}10{sup 6}) spectroscopy in the photon energy region of 60-120 eV. This instrument is expected to provide experimental results which sensitively test models of correlated electron processes in atomic molecular physics. The design criteria and consequent technical challenges posed by the short wavelengths of x-rays and desired resolving power are discussed. The fundamental and practical aspects of soft x-ray interferometry are also explored.
Date: August 1, 1995
Creator: Moler, E. J.; Hussain, Z.; Duarte, R. M. & Howells, M. R.
Object Type: Article
System: The UNT Digital Library
The Si(100)-Sb 2{times}1 and Ge(100) 2{times}1 surfaces: A multi-technique study (open access)

The Si(100)-Sb 2{times}1 and Ge(100) 2{times}1 surfaces: A multi-technique study

The electronic and geometric structures of the clean and Sb terminated Si(100)2{times}1 and Ge(100)-2{times}1 surfaces have been investigated using a multi-technique approach. Low energy electron diffraction (LEED), scanning tunneling microscopy (STM), surface extended X-ray absorption fine structure (SEXAFS) spectroscopy and angle-integrated core-level photoemission electron spectroscopy (PES) were employed to measure the surface symmetry, defect structure, relevant bond lengths, atomic coordination and electronic structure. By employing a multi-technique approach, it is possible to correlate changes in the geometric structure to specific features of the core-level lineshape of the substrate. This allows for the assignment of components of the core-level lineshape to be assigned to specific surface and near-surface atoms.
Date: August 1, 1993
Creator: Richter, M.
Object Type: Report
System: The UNT Digital Library
Large-Scale Eigenvalue Calculations for Stability Analysis of Steady Flows on Massively Parallel Computers (open access)

Large-Scale Eigenvalue Calculations for Stability Analysis of Steady Flows on Massively Parallel Computers

We present an approach for determining the linear stability of steady states of PDEs on massively parallel computers. Linearizing the transient behavior around a steady state leads to a generalized eigenvalue problem. The eigenvalues with largest real part are calculated using Arnoldi's iteration driven by a novel implementation of the Cayley transformation to recast the problem as an ordinary eigenvalue problem. The Cayley transformation requires the solution of a linear system at each Arnoldi iteration, which must be done iteratively for the algorithm to scale with problem size. A representative model problem of 3D incompressible flow and heat transfer in a rotating disk reactor is used to analyze the effect of algorithmic parameters on the performance of the eigenvalue algorithm. Successful calculations of leading eigenvalues for matrix systems of order up to 4 million were performed, identifying the critical Grashof number for a Hopf bifurcation.
Date: August 1, 1999
Creator: Lehoucq, Richard B. & Salinger, Andrew G.
Object Type: Report
System: The UNT Digital Library
RELAP5/MOD3 code manual: User`s guide and input requirements. Volume 2 (open access)

RELAP5/MOD3 code manual: User`s guide and input requirements. Volume 2

The RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant system and the core for loss-of-coolant accidents, and operational transients, such as anticipated transient without scram, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling approach is used that permits simulating a variety of thermal hydraulic systems. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater systems. Volume II contains detailed instructions for code application and input data preparation.
Date: August 1, 1995
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The DART dispersion analysis research tool: A mechanistic model for predicting fission-product-induced swelling of aluminum dispersion fuels. User`s guide for mainframe, workstation, and personal computer applications (open access)

The DART dispersion analysis research tool: A mechanistic model for predicting fission-product-induced swelling of aluminum dispersion fuels. User`s guide for mainframe, workstation, and personal computer applications

This report describes the primary physical models that form the basis of the DART mechanistic computer model for calculating fission-product-induced swelling of aluminum dispersion fuels; the calculated results are compared with test data. In addition, DART calculates irradiation-induced changes in the thermal conductivity of the dispersion fuel, as well as fuel restructuring due to aluminum fuel reaction, amorphization, and recrystallization. Input instructions for execution on mainframe, workstation, and personal computers are provided, as is a description of DART output. The theory of fission gas behavior and its effect on fuel swelling is discussed. The behavior of these fission products in both crystalline and amorphous fuel and in the presence of irradiation-induced recrystallization and crystalline-to-amorphous-phase change phenomena is presented, as are models for these irradiation-induced processes.
Date: August 1, 1995
Creator: Rest, J.
Object Type: Report
System: The UNT Digital Library