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Title: Independent assessment of TRAC-PD2 and RELAP5/MOD1 codes at BNL in FY 1981. [PWR]

Abstract

This report documents the independent assessment calculations performed with the TRAC-PD2 and RELAP/MOD1 codes at Brookhaven National Laboratory (BNL) during Fiscal Year 1981. A large variety of separate-effects experiments dealing with (1) steady-state and transient critical flow, (2) level swell, (3) flooding and entrainment, (4) steady-state flow boiling, (5) integral economizer once-through steam generator (IEOTSG) performance, (6) bottom reflood, and (7) two-dimensional phase separation of two-phase mixtures were simulated with TRAC-PD2. In addition, the early part of an overcooling transient which occurred at the Rancho Seco nuclear power plant on March 20, 1978 was also computed with an updated version of TRAC-PD2. Three separate-effects tests dealing with (1) transient critical flow, (2) steady-state flow boiling, and (3) IEOTSG performance were also simulated with RELAP5/MOD1 code. Comparisons between the code predictions and the test data are presented.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Lab., Upton, NY (USA)
OSTI Identifier:
6363663
Report Number(s):
NUREG/CR-3148; BNL-NUREG-51645
ON: DE83013653
DOE Contract Number:
AC02-76CH00016
Resource Type:
Technical Report
Resource Relation:
Other Information: Portions are illegible in microfiche products
Country of Publication:
United States
Language:
English
Subject:
22 GENERAL STUDIES OF NUCLEAR REACTORS; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; PWR TYPE REACTORS; REACTOR ACCIDENTS; HEAT TRANSFER; HYDRAULICS; COMPARATIVE EVALUATIONS; COMPUTER CALCULATIONS; CRITICAL FLOW; FLOW RATE; PRESSURE GRADIENTS; REACTOR SAFETY; TEMPERATURE GRADIENTS; VOID FRACTION; ACCIDENTS; ENERGY TRANSFER; FLUID FLOW; FLUID MECHANICS; MECHANICS; REACTORS; SAFETY; WATER COOLED REACTORS; WATER MODERATED REACTORS; 220900* - Nuclear Reactor Technology- Reactor Safety; 210200 - Power Reactors, Nonbreeding, Light-Water Moderated, Nonboiling Water Cooled

Citation Formats

Saha, P, Jo, J H, Neymotin, L, Rohatgi, U S, and Slovik, G. Independent assessment of TRAC-PD2 and RELAP5/MOD1 codes at BNL in FY 1981. [PWR]. United States: N. p., 1982. Web. doi:10.2172/6363663.
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Saha, P, Jo, J H, Neymotin, L, Rohatgi, U S, & Slovik, G. Independent assessment of TRAC-PD2 and RELAP5/MOD1 codes at BNL in FY 1981. [PWR]. United States. doi:10.2172/6363663.
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Saha, P, Jo, J H, Neymotin, L, Rohatgi, U S, and Slovik, G. Wed . "Independent assessment of TRAC-PD2 and RELAP5/MOD1 codes at BNL in FY 1981. [PWR]". United States. doi:10.2172/6363663. https://www.osti.gov/servlets/purl/6363663.
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@article{osti_6363663,
title = {Independent assessment of TRAC-PD2 and RELAP5/MOD1 codes at BNL in FY 1981. [PWR]},
author = {Saha, P and Jo, J H and Neymotin, L and Rohatgi, U S and Slovik, G},
abstractNote = {This report documents the independent assessment calculations performed with the TRAC-PD2 and RELAP/MOD1 codes at Brookhaven National Laboratory (BNL) during Fiscal Year 1981. A large variety of separate-effects experiments dealing with (1) steady-state and transient critical flow, (2) level swell, (3) flooding and entrainment, (4) steady-state flow boiling, (5) integral economizer once-through steam generator (IEOTSG) performance, (6) bottom reflood, and (7) two-dimensional phase separation of two-phase mixtures were simulated with TRAC-PD2. In addition, the early part of an overcooling transient which occurred at the Rancho Seco nuclear power plant on March 20, 1978 was also computed with an updated version of TRAC-PD2. Three separate-effects tests dealing with (1) transient critical flow, (2) steady-state flow boiling, and (3) IEOTSG performance were also simulated with RELAP5/MOD1 code. Comparisons between the code predictions and the test data are presented.},
doi = {10.2172/6363663},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Dec 01 00:00:00 EST 1982},
month = {Wed Dec 01 00:00:00 EST 1982}
}
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Technical Report:
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DOI:  10.2172/6363663
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    This report presents the results of independent code assessment conducted at BNL. The TRAC-PF1 (Version 7.0) and RELAP5/MOD1 (Cycle 14) codes were assessed using the critical flow tests, level swell test, countercurrent flow limitation (CCFL) tests, post-CHF test, steam generator thermal performance tests, and natural circulation tests. TRAC-BD1 (Version 12.0) was applied only to the CCFL and post-CHF tests. The TRAC-PWR series of codes, i.e., TRAC-P1A, TRAC-PD2, and TRAC-PF1, have been gradually improved. However, TRAC-PF1 appears to need improvement in almost all categories of tests/phenomena attempted to BNL. Of the two codes, TRAC-PF1 and RELAP5/MOD1, the latter needs more improvementmore » particularly in the areas of: CCFL, Level swell, CHF correlation and post-CHF heat transfer, and Numerical stability. For the CCFL and post-CHF tests, TRAC-BD1 provides the best overall results. However, the TRAC-BD1 interfacial shear package for the countercurrent annular flow regime needs further improvement for better prediction of CCFL phenomenon. 47 refs., 87 figs., 15 tabs.« less

  • ; ; ; ...
    Independent assessment of the advanced codes such as TRAC and RELAP5 has continued at BNL through the Fiscal Year 1982. The simulation tests can be grouped into the following five categories: critical flow, counter-current flow limiting (CCFL) or flooding, level swell, steam generator thermal performance, and natural circulation. TRAC-PF1 (Version 7.0) and RELAP5/MOD1 (Cycle 14) codes were assessed by simulating all of the above experiments, whereas the TRAC-BD1 (Version 12.0) code was applied only to the CCFL tests. Results and conclusions of the BNL code assessment activity of FY 1982 are summarized below.

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