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Kinetic analysis of dynamic PET data

Description: Our goal is to quantify regional physiological processes such as blood flow and metabolism by means of tracer kinetic modeling and positron emission tomography (PET). Compartmental models are one way of characterizing the behavior of tracers in physiological systems. This paper describes a general method of estimating compartmental model rate constants from measurements of the concentration of tracers in blood and tissue, taken at multiple time intervals. A computer program which applies the me… more
Date: December 1, 1983
Creator: Knittel, B.
Partner: UNT Libraries Government Documents Department
open access

TRAC analysis and support of Oconee-1 PTS studies. [Pressurized thermal shock following overcooling transients]

Description: This paper describes the overall pressurized thermal shock (PTS) program at Los Alamos with emphasis on TRAC-PF1 calculations of severe overcooling transients for the Oconee-1 pressurized water reactor (PWR). A summary of results for several calculations are presented for the Oconee-1 PWR along with detailed discussions of two of the most severe overcooling transients predicted (main steam-line break and turbine-bypass valve (TBV) failures). The calculations performed were plant specific in tha… more
Date: January 1, 1983
Creator: Ireland, J.R.
Partner: UNT Libraries Government Documents Department
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Nonlinear bending and collapse analysis of a poked cylinder and other point-loaded cylinders

Description: This paper analyzes the geometrically nonlinear bending and collapse behavior of an elastic, simply supported cylindrical shell subjected to an inward-directed point load applied at midlength. The large displacement analysis results for this thin (R/t = 638) poked cylinder were obtained from the STAGSC-1 finite element computer program. STAGSC-1 results are also presented for two other point-loaded shell problems: a pinched cylinder (R/t = 100), and a venetian blind (R/t = 250).
Date: June 1, 1983
Creator: Sobel, L.H.
Partner: UNT Libraries Government Documents Department
open access

BNL severe-accident sequence experiments and analysis program. [PWR; BWR]

Description: In the analysis of degraded core accidents, the two major sources of pressure loading on light water reactor containments are: steam generation from core debris-water thermal interactions; and molten core-concrete interactions. Experiments are in progress at BNL in support of analytical model development related to aspects of the above containment loading mechanisms. The work supports development and evaluation of the CORCON (Muir, 1981) and MARCH (Wooton, 1980) computer codes. Progress in the … more
Date: January 1, 1983
Creator: Greene, G.A.; Ginsberg, T. & Tutu, N.K.
Partner: UNT Libraries Government Documents Department
open access

Radiation-damage calculations with NJOY

Description: Atomic displacement, gas production, transmutation, and nuclear heating can all be calculated with the NJOY nuclear data processing system using evaluated data in ENDF/B format. Using NJOY helps assure consistency between damage cross sections and those used for transport, and NJOY provides convenient interface formats for linking data to application codes. Unique features of the damage calculation include a simple momentum balance treatment for radiative capture and a new model for (n, particl… more
Date: January 1, 1983
Creator: MacFarlane, R.E.; Muir, D.W. & Mann, F.W.
Partner: UNT Libraries Government Documents Department
open access

Peach Bottom turbine-trip Test 3 analysis with RELAP5 code

Description: The Peach Bottom turbine trip tests provide excellent benchmark problems for transient analysis of a boiling water reactor (BWR). Analyses of the three turbine trip tests with the RELAP3B/BNL-TWIGL, RETRAN and other codes have been documented. The non-equilibrium, two fluid thermal-hydraulic code-RELAP5/MOD1 was recently used to analyze the test at low power, Test 1. This paper presents the analysis of the more severe transient, Test 3, with the RELAP5 code and provides a comparison of the calc… more
Date: January 1, 1983
Creator: Lu, M.S.
Partner: UNT Libraries Government Documents Department
open access

Tune shifts due to systematic errors in bend magnets

Description: The presence of systematic error multipoles in bend magnets, persistent currents at low magnet excitation, and saturation effects at high magnet excitation may all lead to tune shifts which could prove detrimental to the operation of the SSC. It is the purpose of this note to report estimates of the magnitude of these tune shifts and the corrector strengths required to circumvent them.
Date: December 1, 1983
Creator: Douglas, D.
Partner: UNT Libraries Government Documents Department
open access

Computer analysis of sodium cold trap design and performance. [LMFBR]

Description: Normal steam-side corrosion of steam-generator tubes in Liquid Metal Fast Breeder Reactors (LMFBRs) results in liberation of hydrogen, and most of this hydrogen diffuses through the tubes into the heat-transfer sodium and must be removed by the purification system. Cold traps are normally used to purify sodium, and they operate by cooling the sodium to temperatures near the melting point, where soluble impurities including hydrogen and oxygen precipitate as NaH and Na/sub 2/O, respectively. A c… more
Date: November 1, 1983
Creator: McPheeters, C.C. & Raue, D.J.
Partner: UNT Libraries Government Documents Department
open access

Digital filtering in a disease detection system

Description: A low-pass, nonrecursive digital filter has been designed to process data in an automated enzyme immunoassay system. The software implemented filter has been installed in the Intel 80/10 system controller. A low-speed sample rate of three samples per second allowed the filter algorithm to be programmed in the high-level FORTRAN language with a resultant execution speed of 0.6 seconds per day array. Fourier techniques are used to derive a zero phase shift filter algorithm from a frequency domain… more
Date: January 1, 1983
Creator: Brown, R. R.
Partner: UNT Libraries Government Documents Department
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TRAC analyses for CCTF and SCTF tests and UPTF design/operation

Description: The 2D/3D Program is a multinational (Germany, Japan, and the United States) experimental and analytical nuclear reactor safety research program. The Los Alamos analysis effort is functioning as a vital part of the 2D/3D program. The CCTF and SCTF analyses have demonstrated that TRAC-PF1 can correctly predict multidimensional, nonequilibrium behavior in large-scale facilities prototypical of actual PWR's. Through these and future TRAC analyses the experimental findings can be related from facil… more
Date: January 1, 1983
Creator: Williams, K.A.
Partner: UNT Libraries Government Documents Department
open access

Severe fuel-damage scoping test performance. [PWR]

Description: As a result of the Three Mile Island Unit-2 (TMI-2) accident, the Nuclear Regulatory Commission has initiated a severe fuel damage test program to evaluate fuel rod and core response during severe accidents similar to TMI-2. The first test of Phase I of this series has been successfully completed in the Power Burst Facility at the Idaho National Engineering Laboratory. Following the first test, calculations were performed using the TRAC-BD1 computer code with actual experimental boundary condit… more
Date: January 1, 1983
Creator: Gruen, G.E. & Buescher, B.J.
Partner: UNT Libraries Government Documents Department
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TRAC independent assessment for PWR analysis

Description: LANL is developing the Transient Reactor Analysis Code (TRAC) for application to PWRs. Goal was to analyze large-break loss-of-coolant accidents (LOCAs), and the TRAC-P1A and TRAC-PD2 codes primarily addressed the large-break LOCA. The TRAC-PF1 code contained modifications which enhanced the computational speed of the code and improved its application to small-break LOCAs. The TRAC-PF1/MOD1 code added improved steam-generator modeling, a turbine component, and a control system together with mod… more
Date: January 1, 1983
Creator: Knight, T. D.
Partner: UNT Libraries Government Documents Department
open access

TRAC calculations of overcooling transients in PWRs for pressurized thermal-shock analysis

Description: This paper briefly describes the overall pressurized thermal shock (PTS) program at Los Alamos with emphasis on TRAC-PF1 calculations of severe overcooling transients in pressurized water reactors (PWRs). Overcooling transients for both the Oconee-1 and Calvert Cliffs-1 nuclear plants have been performed. A summary of results for several calculations are presented for the Oconee-1 PWR along with detailed discussions of two of the most severe overcooling transients predicted (main steam-line bre… more
Date: January 1, 1983
Creator: Ireland, J. R. & Boyack, B. E.
Partner: UNT Libraries Government Documents Department
open access

Three-dimensional thermal-hydraulic calculations using SOLA-PTS

Description: The transient, three-dimensional SOLA-PTS code has been used to study the thermal-hydraulic mixing of HPI and ambient fluids in the cold leg and downcomer with application to the pressurized thermal-shock problem. Comparisons of calculated results with 1/5th-scale experimental data are presented and shown to be in good agreement. Also shown are results obtained at full scale for a Combustion Engineering plant (Calvert Cliffs-1) following an assumed main-streamline-break accident.
Date: January 1, 1983
Creator: Daly, B. J. & Torrey, M. D.
Partner: UNT Libraries Government Documents Department
open access

TRAC-PF1: pressurized-thermal shock calculations for several small-break loss-of-coolant accident transients in the Oconee-1 nuclear power plant

Description: This paper presents the thermal-hydraulic response of the Oconee-1 plant to several small-break loss-of-coolant accidents and a description of the TRAC-PF1 plant model of Oconee-1 used in support of the Nuclear Regulatory Commission directed pressurized thermal shock study. The small-break transients investigated included a stuck-open power-operated-relief-valve, a 2-in.-diam surge line break, and a 4-in.-diam surge line break. The results of the TRAC-PF1 calculations indicated that none of the… more
Date: January 1, 1983
Creator: Burkett, M. W. & Bassett, B.
Partner: UNT Libraries Government Documents Department
open access

TRAC-PF1 analysis of LOFT steam-generator feedwater transient test L9-1. [PWR]

Description: The Transient Reactor Analysis Code (TRAC-PF1) calculations were compared to test data from Loss-of-Fluid Test (LOFT) L9-1, which was a loss-of-feedwater transient. This paper includes descriptions of the test and the TRAC input and compares the TRAC-calculated results with the test data. We conclude that the code predicted the experiment well, given the uncertainties in the boundary conditions. The analysis indicates the need to model all the flow paths and heat structures, and to improve the … more
Date: January 1, 1983
Creator: Meier, J.K.
Partner: UNT Libraries Government Documents Department
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TRAC analysis of the Crystal River Unit-3 Plant transient of February 26, 1980

Description: This paper describes the application of the TRAC-PD2 and TRAC-PF1 codes to analyze the Crystal River transient. The PD2 and PF1 analyses used the three-dimensional and one-dimensional vessel models, respectively. Both calculations predicted the plant depressurization caused by the open PORV and the subsequent repressurization caused by closing the PORV and continuing high-pressure injection flow. Also, natural circulation was calculated in loop B following reestablishment of feedwater to the lo… more
Date: January 1, 1983
Creator: Coddington, P. & Willcutt, G.J.E. Jr.
Partner: UNT Libraries Government Documents Department
open access

Processing time using Datatrieve-11, clunks, and FORTRAN

Description: Although Datatrieve-11 processes dates with 100-ns resolution using clunks, it has no provision for processing time. This paper describes a set of Datatrieve-11 procedures and FORTRAN-callable subroutines for handling time, as well as dates, expressed in clunks. Although the FORTRAN-callable subroutines use RMS modules, these modules can be extracted from the appropriate RMS library, allowing FORTRAN programs to be linked to an FCS library instead of to RMS.
Date: January 1, 1983
Creator: Horning, R. R. & Goode, W. E.
Partner: UNT Libraries Government Documents Department
open access

Decontamination analysis of the NUWAX-83 accident site using DECON

Description: This report presents an analysis of the site restoration options for the NUWAX-83 site, at which an exercise was conducted involving a simulated nuclear weapons accident. This analysis was performed using a computer program deveoped by Pacific Northwest Laboratory. The computer program, called DECON, was designed to assist personnel engaged in the planning of decontamination activities. The many features of DECON that are used in this report demonstrate its potential usefulness as a site restor… more
Date: November 1, 1983
Creator: Tawil, J.J.
Partner: UNT Libraries Government Documents Department
open access

Neutral transport in the ALT-I limiter

Description: The behavior of neutral atoms and molecules in the TEXTOR pump limiter ALT-I has been investigated with the aid of the 2-D Monte Carlo neutral transport code DEGAS. The code incorporates the full set of relevant collision processes (atomic and molecular), and it has a standard wall model which includes fast-neutral reflection and molecular desorption. The limiter was modeled with a 2-D geometry, which included corrections for 3-D effects. Among the quantities predicted by the code which are dir… more
Date: October 1, 1983
Creator: Boley, C. D.; Heifetz, D. B.; Post, D. E. & Malinowski, M. E.
Partner: UNT Libraries Government Documents Department
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Vectorizing and machine-spanning techniques

Description: Techniques for vectorizing complex logic are shown using a decoupled sliding-surface calculation that is part of a two-dimensional Lagrangian simulation model. The same source coding can be run on many vector, parallel, and multiprocessor computers with very little or no alteration. The vectorizing techniques have been used for a wide range of problems.
Date: September 22, 1983
Creator: Giroux, E D
Partner: UNT Libraries Government Documents Department
open access

Radiation transport in numerical astrophysics

Description: In this article, we discuss some of the numerical techniques developed by Jim Wilson and co-workers for the calculation of time-dependent radiation flow. Difference equations for multifrequency transport are given for both a discrete-angle representation of radiation transport and a Fick's law-like representation. These methods have the important property that they correctly describe both the streaming and diffusion limits of transport theory in problems where the mean free path divided by char… more
Date: February 1, 1983
Creator: Lund, C.M.
Partner: UNT Libraries Government Documents Department
open access

Mode conversion and electron heating near the upper hybrid resonance frequency

Description: Mode conversion near the upper hybrid resonance frequency and electron heating are studied using a one-dimensional electromagnetic relativistic particle code. It is found that for a sufficiently small pump field E/sub 0/, E/sub 0//sup 2//4..pi..nT/sub e/ less than or equal to 0.01, electron heating is localized in a region near the electron cyclotron layer where the pump frequency is equal to the local electron gyrofrequency. For stronger pump fields, electron heating takes place more or less u… more
Date: November 1, 1983
Creator: Smith, B. L.; Okuda, H. & Abe, H.
Partner: UNT Libraries Government Documents Department
open access

Development of a benchmark data base for use in PWR dosimetry analysis

Description: A newly conceived code system, LEPRICON, is being developed by the Oak Ridge National Laboratory through a contract with the Electric Power Research Institute to provide updated estimates and uncertainties in fast-neutron fluences at points of weakness in the pressure vessels of operating PWR's from information derived from surveillance dosimetry. The uniqueness of the LEPRICON methodology compared with existing methods lies in its capacity to establish the uncertainties of both the calculated … more
Date: January 1, 1983
Creator: Maerker, R.E.; Broadhead, B.L.; Williams, M.L. & Wagschal, J.J.
Partner: UNT Libraries Government Documents Department
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