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Space-charge-dominated beam dynamics simulations using the massively parallel processors (MPPs) of the Cray T3D

Description: Computer simulations using the multi-particle code PARMELA with a three-dimensional point-by-point space charge algorithm have turned out to be very helpful in supporting injector commissioning and operations at Thomas Jefferson National Accelerator Facility (Jefferson Lab, formerly called CEBAF). However, this algorithm, which defines a typical N{sup 2} problem in CPU time scaling, is very time-consuming when N, the number of macro-particles, is large. Therefore, it is attractive to use massiv… more
Date: October 1, 1996
Creator: Liu, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Clean energy from municipal solid waste. Technical progress report number 3

Description: Development of the computer models for slurry carbonization have begun and were based upon the collected data (mass balances, yield, temperatures, and pressures) from the previous pilot plant campaigns. All computer models are being developed with Aspen`s SpeedUp{trademark} software. The primary flow sheet with major alternatives has been developed and the majority of equipment descriptions and models, cost algorithms, and baseline parameters have been input to SpeedUp. The remaining modeling p… more
Date: January 5, 1996
Creator: Klosky, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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FIDAP Capabilities for Solving Problems With Stiff Chemistry

Description: In support of the Motorola CRADA, the capabilities of the computational fluid dynamics code FIDAP (Fluid Dynamics International) for simulating problems involving fluid flow, heat transport, and chemical reactions have been assessed and enhanced as needed for semiconductor-processing applications (e.g. chemical vapor deposition). A novel method of treating surface chemical species that uses only pre-existing FIDAP commands is described and illustrated with test problems. A full-Jacobian treatme… more
Date: September 1, 1996
Creator: Torczynski, J. R. & Baer, T. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

ORFIN: An electric utility financial and production simulator

Description: With the coming changes in the electrical industry, there is a broad need to understand the impacts of restructuring on customers, existing utilities, and other stakeholders. Retail wheeling; performance-based regulation; unbundling of generation, transmission, and distribution; and the impact of stranded commitments are all key issues in the discussions of the future of the industry. To quantify these issues, financial and production cost models are required. The authors have created a smaller… more
Date: March 1, 1996
Creator: Hadley, Stanton W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Numerical simulations of Hurricane Bertha using a mesoscale atmospheric model

Description: The Regional Atmospheric Model System (RAMS) has been used to simulate Hurricane Bertha as it moved toward and onto shore during the period July 10--12, 1996. Using large-scale atmospheric data from 00 UTC, 11 July (Wednesday evening) to initialize the model, a 36-hour simulation was created for a domain centered over the Atlantic Ocean east of the Florida coast near Jacksonville. The simulated onshore impact time of the hurricane was much earlier than observed (due to the use of results from t… more
Date: August 1, 1996
Creator: Buckley, Robert L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Supernova-Relevant Hydrodynamic Instability Experiment on the Nova Laser

Description: Supernova 1987A focused attention on the critical role of hydrodynamic instabilities in the evolution of supernovae. On quite a separate front, the detrimental effect of hydrodynamic instabilities in inertial confinement fusion (ICF) has long been known. Tools from both areas are being tested on a common project. At Lawrence Livermore National Laboratory (LLNL), the Nova Laser is being used in scaled laboratory experiments of hydrodynamic mixing under supernova-relevant conditions. Numerical si… more
Date: February 12, 1996
Creator: Kane, J.; Arnett, D.; Remington, B. A.; Glendinning, S. G.; Castor, J.; Rubenchik, A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Simulations of Laser Imprint for Nova Experiments and for Ignition Capsules. Revision 1

Description: In direct drive ICF, nonuniformities in laser illumination seed ripples at the ablation front in a process called ``imprint``. These nonuniformities grow during the capsule implosion and, if initially large enough, can penetrate the capsule shell, impede ignition, or degrade burn. Imprint has been simulated for recent experiments performed on the Nova laser at LLNL examining a variety of beam smoothing conditions. Most used laser intensities similar to the early part of an ignition capsule puls… more
Date: December 1, 1996
Creator: Weber, S. V.; Glendinning, S. G.; Kalantar, D. H.; Key, M. H.; Remington, B. A.; Rothenberg, J. L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Progress Report for 1995-1996

Description: We have been involved in several projects during the present contract period. These include completion of our work on the RD94 test runs performed at the Alternating Gradient Synchrotron (AGS) at Brookhaven; the PhD. thesis project of Ziyang Zhang which was completed during the year, was based on this work. We have continued our Monte Carlo simulation work. This includes studies of trigger rates in the muon identifier of the PHENIX experiment for RHIC. In addition to this we have continued our … more
Date: June 1, 1996
Creator: He, Xiaochun; Lee, William; Petitt, G.A. & Zhang, Ziyang
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Lightweight computational steering of very large scale molecular dynamics simulations

Description: We present a computational steering approach for controlling, analyzing, and visualizing very large scale molecular dynamics simulations involving tens to hundreds of millions of atoms. Our approach relies on extensible scripting languages and an easy to use tool for building extensions and modules. The system is extremely easy to modify, works with existing C code, is memory efficient, and can be used from inexpensive workstations and networks. We demonstrate how we have used this system to ma… more
Date: September 1, 1996
Creator: Beazley, David M. & Lomdahl, Peter S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Some recent developments in treatment planning software and methodology for BNCT

Description: Over the past several years the Idaho National Engineering Laboratory (INEL) has led the development of a unique, internationally-recognized set of software modules (BNCT-rtpe) for computational dosimetry and treatment planning for Boron Neutron Capture Therapy (BNCT). The computational capability represented by this software is essential to the proper administration of all forms of radiotherapy for cancer. Such software addresses the need to perform pretreatment computation and optimization of… more
Date: December 1996
Creator: Nigg, D. W.; Wheeler, F. J. & Wessol, D. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Optimizing Advanced Power System Designs Under Uncertainty

Description: This paper describes recent developments in ongoing research to develop and demonstrate advanced computer-based methods for dealing with uncertainties that are critical to the design of advanced coal-based power systems. Recent developments include new deterministic and stochastic methods for simulation, optimization, and synthesis of advanced process designs. Results are presented illustrating the use of these new modeling tools for the design and analysis of several advanced systems of curren… more
Date: December 31, 1996
Creator: Rubin, E.S.; Diwekar & Frey, H.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Vibration Virtual Environment for Test Optimization (VETO)

Description: A new test simulation tool is being developed to support vibration test design and to evaluate the overall testability of a component or system. This environment, the Vibration Virtual Environment for Test Optimization (VETO), is utilized to optimally place vibration control and response transducers and to investigate the selection of test parameters needed in the design and performance of a vibration experiment. The engineer can investigate the effects of different control parameters prior to … more
Date: October 1, 1996
Creator: Klenke, S. E.; Lauffer, J. P.; Gregory, D. L. & Togami, T. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Prediction and characterization of complex systems

Description: Complex systems are difficult to characterize and to simulate. By considering a series of explicit systems, through experiments and analysis, this project has shown that dynamical systems can be used to model complex systems. A complex dynamical system requires an exponential amount of computer work to simulate accurately. Direct methods are not practical and it is only by an hierarchical approach that one can gain control over the exponential behavior. This allows the development of efficient … more
Date: October 1, 1996
Creator: Mainieri, R.; Baer, M. & Brand, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Lower extremity finite element model for crash simulation

Description: A lower extremity model has been developed to study occupant injury mechanisms of the major bones and ligamentous soft tissues resulting from vehicle collisions. The model is based on anatomically correct digitized bone surfaces of the pelvis, femur, patella and the tibia. Many muscles, tendons and ligaments were incrementally added to the basic bone model. We have simulated two types of occupant loading that occur in a crash environment using a non-linear large deformation finite element code.… more
Date: March 1, 1996
Creator: Schauer, D. A. & Perfect, S. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Validation of DWPF MOG dynamics model -- Phase 1

Description: The report documents the results of a study to validate the DWPF melter off-gas system dynamics model using the data collected during the Waste Qualification Runs in 1995. The study consisted of: (1) calibration of the model using one set of melter idling data, (2) validation of the calibrated model using three sets of steady feeding and one set of transient data, and (3) application of the validated model to simulate the melter overfeeding incident which took place on 7/5.95. All the controlle… more
Date: September 23, 1996
Creator: Choi, A.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

RDD-100 model development for TWRS

Description: The purpose of this document is to describe the work performed to develop an executable model of the TWRS technical baseline using the RDD-100 Dynamic Verification Facility. The benefit of developing a DVF model that simulates the conceptual TWRS baseline system is that is provides a verification of the system performance and the traceability needed between the system requirements and the proposed architectures that will satisfy the requirements and perform the identified functions. The initial… more
Date: October 1, 1996
Creator: Gneiting, B. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Computational brittle fracture using smooth particle hydrodynamics

Description: We are developing statistically based, brittle-fracture models and are implementing them into hydrocodes that can be used for designing systems with components of ceramics, glass, and/or other brittle materials. Because of the advantages it has simulating fracture, we are working primarily with the smooth particle hydrodynamics code SPBM. We describe a new brittle fracture model that we have implemented into SPBM. To illustrate the code`s current capability, we have simulated a number of experi… more
Date: October 1, 1996
Creator: Mandell, D. A.; Wingate, C. A. & Schwalbe, L. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

An acid-gas removal system for upgrading subquality natural gas

Description: The objective of this project is to develop systems to reduce the cost of treating subquality natural gas. Based on over 1,000 laboratory experiments on vapor-liquid equilibria and mass transfer and simulation studies, the use of N-Formyl Morpholine as a solvent together with structured packings has the following advantages: high capacity for H{sub 2}S and CO{sub 2} removal; little or no refrigeration required; less loss of hydrocarbons (CH{sub 4}, C{sub 2}-C{sub 6}); and dehydration potential.… more
Date: September 1, 1996
Creator: Palla, N.; Lee, A.L.; Leppin, D.; Shoemaker, H.D.; Hooper, H.M.; Emmrich, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Selecting computer models and input parameters for analysis of environmental impacts

Description: Computer models are powerful tools for analyzing complex impacts on air quality, groundwater quality, human health, and ecological resources. This paper examines some of the challenges involved in using computer models for environmental impacts analysis. The paper presents approaches for helping technical specialists and managers work together and assure that the modeling process is effective.
Date: September 1, 1996
Creator: Meier, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Structural stability vs. thermal performance: old dilemma, new solutions

Description: In many building envelopes, actual thermal performance falls quite a bit short of nominal design parameters given in standards. Very often only windows, doors, and a small part of the wall area meet standards requirements. In the other parts of the building envelope, unaccounted thermal bridges reduce the effective thermal resistance of the insulation material. Such unaccounted heat losses compromise the thermal performance of the whole building envelope. For the proper analysis of the thermal … more
Date: October 1, 1996
Creator: Kosny, J. & Christian, J.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Long-term simulation of turbulence-induced loads using the SNLWIND-3D, FAST, YawDyn, and ADAMS numerical codes

Description: Notable progress was made in simulating the dynamic response of operating wind turbines during the past several years. In concert with these activities, the ability to adequately simulate the characteristics of the turbulent inflow, which is directly or indirectly responsible for much of the observed response, has also improved significantly. Recent investigations have shown that without such inflow simulations, it is often difficult to predict fatigue-load distributions that agree with observa… more
Date: October 1, 1996
Creator: Kelley, N. D.; Wright, A. D.; Buhl Jr., M. L. & Tangler, J. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Modeling of eddy current probe response for steam generator tubes

Description: Sample calculations were performed with a three-dimensional (3-D) finite-element model analysis that describe the response of an eddy current (EC) probe to steam generator (SG) tubing artifacts. Such calculations could be very helpful in understanding and interpreting of EC probe response to complex tube/defect geometries associated with the inservice inspection (ISI) of steam generator (SG) tubing. The governing field equations are in terms of coupled magnetic vector and electric scalar potent… more
Date: December 1, 1996
Creator: Bakhtiari, S. & Kupperman, D.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling water retention of sludge simulants and actual saltcake tank wastes

Description: The Ferrocyanide Tanks Safety Program managed by Westinghouse hanford Company has been concerned with the potential combustion hazard of dry tank wastes containing ferrocyanide chemical in combination with nitrate salts. Pervious studies have shown that tank waste containing greater than 20 percent of weight as water could not be accidentally ignited. Moreover, a sustained combustion could not be propagated in such a wet waste even if it contained enough ferrocyanide to burn. Because moisture c… more
Date: July 1, 1996
Creator: Simmons, C.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Evolution of surface roughness during CVD growth

Description: Monte Carlo simulations of physical and chemical vapor deposition are used to study roughening kinetics of films that grow by nucleation and coalescence of clusters. The effects of interlayer transport, preferential dissociation of molecular precursors and energetic differences between the clusters and the substrate are examined.
Date: December 31, 1996
Creator: Chason, E.; Mayer, T.M. & Adams, D.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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