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RODCON: a finite difference heat conduction computer code in cylindrical coordinates

Description: RODCON, a finite difference computer code, was developed to calculate the internal temperature distribution of the fuel rod simulator (FRS) for the Core Flow Test Loop (CFTL). RODCON solves the implicit, time-dependent forward-differencing heat transfer equation in 2-dimensional (Rtheta) cylindrical coordinates at an axial plane with user specified radial material zones and surface conditions at the FRS periphery. Symmetry of the boundary conditions of coolant bulk temperatures and film coeffic… more
Date: September 16, 1980
Creator: Conklin, J. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Prediction of the migration of several radionuclides in ocean sediment with the computer code IONMIG: a preliminary report

Description: A computer code, IONMIG, which is used to calculate the far-field transport of radionuclides through ocean sediment by diffusion and convection is described. The code uses a two-dimensional, axisymmetric, explicit finite difference formulation. Preliminary results for several species (Cs, Pu, I, Tc) are given.
Date: May 1, 1980
Creator: Russo, A.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Three-dimensional thermal analysis of a baseline spent fuel repository

Description: A three-dimensional thermal analysis has been performed using finite difference techniques to determine the near-field response of a baseline spent fuel repository in a deep geologic salt medium. A baseline design incorporates previous thermal modeling experience and OWI recommendations for areal thermal loading in specifying the waste form properties, package details, and emplacement configuration. The base case in this thermal analysis considers one 10-year old PWR spent fuel assembly emplace… more
Date: June 5, 1980
Creator: Altenbach, T.J. & Lowry, W.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ion-temperature-gradient instability in toroidal plasmas

Description: The stability of the ion-temperature-gradient mode in a toroidal plasma is investigated. Using the ballooning-mode formalism, an ordinary difference-differential equation is derived which includes full kinetic effects. The equation is, then, examined in various limits where it reduces to an ordinary differential equation. Analytic and computational studies show that, for eta/sub i/ identical with d lnT/sub i//d lnn > 1, toroidal effects further destabilize the mode and, hence, the corresponding… more
Date: March 1, 1980
Creator: Guzdar, P.N.; Chen, L.; Tang, W.M. & Rutherford, P.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Specifications for the development of a fully three-dimensional numerical groundwater model for regional mass transport of radionuclides from a deep waste repository

Description: Specifications are given which are necessary to develop a three-dimensional numerical model capable of simulating regional mass transport of radionuclides from a deep waste repository. The model to be developed will include all of the significant mass transport processes including flow, chemical, and thermal advection, mechanical dispersion, molecular diffusion, ion exchange reactions, and radioactive decay. The model specifications also include that density and viscosity fluid properties be fu… more
Date: April 1, 1980
Creator: Prickett, T.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Conversion and improvement of the Rutherford Laboratory's magnetostatic computer code GFUN3D to the NMFECC CDC 7600

Description: The implementation of a version of the Rutherford Laboratory's magnetostatic computer code GFUN3D on the CDC 7600 at the National Magnetic Fusion Energy Computer Center is reported. A new iteration technique that greatly increases the probability of convergence and reduces computation time by about 30% for calculations with nonlinear, ferromagnetic materials is included. The use of GFUN3D on the NMFE network is discussed, and suggestions for future work are presented. Appendix A consists of rev… more
Date: June 1, 1980
Creator: Tucker, T.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Overview of image reconstruction

Description: Image reconstruction (or computerized tomography, etc.) is any process whereby a function, f, on R/sup n/ is estimated from empirical data pertaining to its integrals, ..integral..f(x) dx, for some collection of hyperplanes of dimension k < n. The paper begins with background information on how image reconstruction problems have arisen in practice, and describes some of the application areas of past or current interest; these include radioastronomy, optics, radiology and nuclear medicine, elect… more
Date: April 1, 1980
Creator: Marr, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Implementing sparse matrix techniques in the ERATO code

Description: The ERATO code computes the stability of an equilibrium with respect to the linear MHD equation. The ERATO code is divided into 5 programs (ERATO1 through ERATO5). This report documents some minor changes made in ERATO3 and a major reorganization of ERATO4. The changes were made to reduce drastically the amount of secondary storage needed by the codes and at the same time improve the efficiency of ERATO4. The ultimate goal is to allow the successful completion of runs with finer meshes than are… more
Date: April 1, 1980
Creator: Scott, D.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrogen mixing in a closed containment compartment based on a 1-D model with convective effects. Final report

Description: A transient one-dimensional finite-difference model was developed to determine the hydrogen concentration variation with position in a closed containment compartment due to radiolysis following a LOCA. The model includes mixing due to molecular and eddy diffusion and natural convection. For representative compartments, the maximum hydrogen concentration difference between the bottom and top of the compartment never exceeds 0.25 volume percent when all three mixing mechanisms are considered for … more
Date: January 1, 1980
Creator: Willcutt, G. J. E., Jr.; Gido, R. G. & Koestel, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Acceleration of the inner iteration of the DOT-IV transport code using a new source correction scheme

Description: A detailed description of the steady-state Boltzmann transport equation is given. Then the discrete ordinates method of solving the transport equation is described. The conventional rebalance method, the source correction scheme of rebalance, and a new source correction scheme involving a correction equation with a modified flow term are derived. Difference equations for each version of the source correction scheme are presented. The different versions of the source correction scheme and the co… more
Date: July 1, 1980
Creator: Aull, J.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transport and dispersion of pollutants in surface impoundments: a finite difference model

Description: A surface impoundment model by finite-difference (SIMFD) has been developed. SIMFD computes the flow rate, velocity field, and the concentration distribution of pollutants in surface impoundments with any number of islands located within the region of interest. Theoretical derivations and numerical algorithm are described in detail. Instructions for the application of SIMFD and listings of the FORTRAN IV source program are provided. Two sample problems are given to illustrate the application an… more
Date: July 1, 1980
Creator: Yeh, G.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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FLUOMEG: a planar finite difference mesh generator for fluid flow problems with parallel boundaries. [In FORTRAN IV]

Description: A two- or three-dimensional finite difference mesh generator capable of discretizing subrectangular flow regions (planar coordinates) with arbitrarily shaped bottom contours (vertical dimension) was developed. This economical, interactive computer code, written in FORTRAN IV and employing DISSPLA software together with graphics terminal, generates first a planar rectangular grid of variable element density according to the geometry and local kinematic flow patterns of a given fluid flow problem… more
Date: May 1, 1980
Creator: Kleinstreuer, C. & Patterson, M.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computer program to fit a hyperellipse to a set of phase-space points in as many as six dimensions. [HELIPS, and COFAC to determine derivatives of determinants, in FORTRAN]

Description: A computer program that will fit a hyperellipse to a set of phase-space points in as many as 6 dimensions was written and tested. The weight assigned to the phase-space points can be varied as a function of their distance from the centroid of the distribution. Varying the weight enables determination of whether there is a difference in ellipse orientation between inner and outer particles. This program should be useful in studying the effects of longitudinal and transverse phase-space couplings. more
Date: March 1, 1980
Creator: Wadlinger, E.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Finite element analysis of arc welding

Description: Analytical models of the gas tungsten-arc welding process into finite element computer programs provides a valuable tool for determining the welding thermal cycle, weld bead shape, and penetration characteristics, as well as for evaluating the stresses and distortions generated as a result of the temperature transients. The analysis procedures are applicable to planar or axisymmetric welds with arbitrary cross-sectional geometries, under quasistationary conditions. The method used for determini… more
Date: January 1980
Creator: Friedman, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Monte Carlo simulations of lattice gauge theories

Description: Monte Carlo simulations done for four-dimensional lattice gauge systems are described, where the gauge group is one of the following: U(1); SU(2); Z/sub N/, i.e., the subgroup of U(1) consisting of the elements e 2..pi..in/N with integer n and N; the eight-element group of quaternions, Q; the 24- and 48-element subgroups of SU(2), denoted by T and O, which reduce to the rotation groups of the tetrahedron and the octahedron when their centers Z/sub 2/, are factored out. All of these groups can b… more
Date: February 1, 1980
Creator: Rebbi, C
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

SHAFT79 user's manual

Description: SHAFT79 (Simultaneous Heat And Fluid Transport) is an integrated finite difference program for computing two-phase non-isothermal flow in porous media. The principal application for which SHAFT79 is designed is in geothermal reservoir simulation. SHAFT79 solves the same equations as an earlier version, called SHAFT78, but uses much more efficient mathematical and numerical methods. The present SHAFT79 user's manual gives a brief account of equations and numerical methods and then describes in d… more
Date: March 1, 1980
Creator: Pruess, K. & Schroeder, R.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Passive stabilization in a linear MHD stability code

Description: Utilizing a Galerkin procedure to calculate the vacuum contribution to the ideal MHD Lagrangian, the implementation of realistic boundary conditions are described in a linear stability code. The procedure permits calculation of the effect of arbitrary conducting structure on ideal MHD instabilities, as opposed to the prior use of an encircling shell. The passive stabilization of conducting coils on the tokamak vertical instability is calculated within the PEST code and gives excellent agreement… more
Date: March 1, 1980
Creator: Todd, A.M.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Software systems research. Annual report, November 16, 1979-November 15, 1980. [Dept. of Computer Sciences, Univ. of Illinois, Urbana]

Description: Progress made during the last year in the following areas is briefly summarized: ODEs with highly oscillatory solutions, ODEs with discontinuities, multirate methods for ODEs, efficient low-accuracy methods for ODEs, iterative methods and sparse techniques for implicit ODE methods, method of lines with variable space mesh, methods for parallel and/or network architectures, software and hardware tools, and other results. This report is administrative in nature, and is not meant to present detail… more
Date: January 1, 1980
Creator: Gear, C.W. & Watanabe, D.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Block relaxation strategies

Description: It is desired to solve the linear system Ax = b, where the matrix A is n x n block tridiagonal with block size m. This system is to be solved by block line relaxation when the largest block problem with block size m that can be cheaply solved directly is l x l. Iteration steps, strategies, and results are summarized. It is concluded that the convergence rate of some block relaxation strategies is much faster than that of the strategies generally used. (RWR)
Date: January 1, 1980
Creator: Faber, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Review of updated Sandia wavecodes for penetration work. [Use of NORML, OBLIK, and TAUTQ]

Description: For the special needs of the Sandia penetrator program, the codes TAUTQ, NORML, and OBLIK were written as modifications of the wavecodes WONDY and TOODY. This report presents a brief outline of the new codes, together with a set of instructions for running them. 1 figure.
Date: February 1, 1980
Creator: Norwood, F. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quadratically convergent MCSCF theory for large-configuration sets

Description: A multi-configuration self-consistent field method for large configuration-sets is presented. It consists in identifying a primary subset containing the predominant configurations and a secondary one containing the rest. The formalism achieves near-quadratic convergence as well as a significant simplification of the orbital-transformation problem by the introduction of Fock equations and Fock matrices.
Date: January 1, 1980
Creator: Das, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Estimation of in-situ thermal conductivities from temperature gradient measurements

Description: A mathematical model has been developed to study the effect of variable thermal conductivity of the formations, and the wellbore characteristics, on the fluid temperature behavior inside the wellbore during injection or production and after shut-in. During the injection or production period the wellbore fluid temperature is controlled mainly by the fluid flow rate and the heat lost from the fluid to the formation. During the shut-in period, the fluid temperature is strongly affected by differen… more
Date: December 1, 1980
Creator: Hoang, V.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Performance predictions of silica-gel desiccant dehumidifiers. Technical report No. 3

Description: The analysis of a cross-cooled desiccant dehumidifier using silica gel in the form of sheets is described. This unit is the principal component of solar powered desiccant air conditioning system. The mathematical model has first been formulated describing the dynamics of the dehumidifier. The model leads to a system of nonlinear coupled heat and mass transfer equations for the sorption processes and linear heat transfer equations for the purging processes. The model accounts for the gas film re… more
Date: January 1, 1980
Creator: Mathiprakasam, B. & Lavan, Z.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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