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Title: Code requirements document: MODFLOW 2. 1: A program for predicting moderator flow patterns

Abstract

Sudden changes in the temperature of flowing liquids can result in transient buoyancy forces which strongly impact the flow hydrodynamics via flow stratification. These effects have been studied for the case of potential flow of stratified liquids to line sinks, but not for moderator flow in SRS reactors. Standard codes, such as TRAC and COMMIX, do not have the capability to capture the stratification effect, due to strong numerical diffusion which smears away the hot/cold fluid interface. A related problem with standard codes is the inability to track plumes injected into the liquid flow, again due to numerical diffusion. The combined effects of buoyant stratification and plume dispersion have been identified as being important in operation of the Supplementary Safety System which injects neutron-poison ink into SRS reactors to provide safe shutdown in the event of safety rod failure. The MODFLOW code discussed here provides transient moderator flow pattern information with stratification effects, and tracks the location of ink plumes in the reactor. The code, written in Fortran, is compiled for Macintosh II computers, and includes subroutines for interactive control and graphical output. Removing the graphics capabilities, the code can also be compiled on other computers. With graphics, in additionmore » to the capability to perform safety related computations, MODFLOW also provides an easy tool for becoming familiar with flow distributions in SRS reactors.« less

Authors:
 [1];  [2]
  1. Univ. of California, Berkeley (United States). Dept. of Nuclear Engineering
  2. Westinghouse Savannah River Co., Aiken, SC (United States)
Publication Date:
Research Org.:
Westinghouse Savannah River Co., Aiken, SC (United States)
Sponsoring Org.:
USDOE; USDOE, Washington, DC (United States)
OSTI Identifier:
7368609
Report Number(s):
WSRC-TR-92-140
ON: DE93017276
DOE Contract Number:  
AC09-89SR18035
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
22 GENERAL STUDIES OF NUCLEAR REACTORS; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; C REACTOR; HYDRAULICS; K REACTOR; L REACTOR; P REACTOR; R REACTOR; APPLE COMPUTERS; COMPUTER GRAPHICS; COMPUTER PROGRAM DOCUMENTATION; DIFFUSION; ENGINEERED SAFETY SYSTEMS; FLUID FLOW; FORTRAN; HYDRODYNAMICS; M CODES; MANUALS; MODERATORS; OPERATION; PERFORMANCE; PLUMES; REACTOR SAFETY; SAVANNAH RIVER PLANT; SPATIAL DISTRIBUTION; STRATIFICATION; TEMPERATURE DISTRIBUTION; COMPUTER CODES; COMPUTERS; DISTRIBUTION; DOCUMENT TYPES; ELECTRONIC CIRCUITS; FLUID MECHANICS; HEAVY WATER MODERATED REACTORS; MECHANICS; MICROELECTRONIC CIRCUITS; MICROPROCESSORS; NATIONAL ORGANIZATIONS; PRODUCTION REACTORS; PROGRAMMING LANGUAGES; REACTORS; SAFETY; SPECIAL PRODUCTION REACTORS; US AEC; US DOE; US ERDA; US ORGANIZATIONS; 220900* - Nuclear Reactor Technology- Reactor Safety; 220600 - Nuclear Reactor Technology- Research, Test & Experimental Reactors; 990200 - Mathematics & Computers

Citation Formats

Peterson, P F, and Paik, I K. Code requirements document: MODFLOW 2. 1: A program for predicting moderator flow patterns. United States: N. p., 1992. Web. doi:10.2172/7368609.
Peterson, P F, & Paik, I K. Code requirements document: MODFLOW 2. 1: A program for predicting moderator flow patterns. United States. https://doi.org/10.2172/7368609
Peterson, P F, and Paik, I K. 1992. "Code requirements document: MODFLOW 2. 1: A program for predicting moderator flow patterns". United States. https://doi.org/10.2172/7368609. https://www.osti.gov/servlets/purl/7368609.
@article{osti_7368609,
title = {Code requirements document: MODFLOW 2. 1: A program for predicting moderator flow patterns},
author = {Peterson, P F and Paik, I K},
abstractNote = {Sudden changes in the temperature of flowing liquids can result in transient buoyancy forces which strongly impact the flow hydrodynamics via flow stratification. These effects have been studied for the case of potential flow of stratified liquids to line sinks, but not for moderator flow in SRS reactors. Standard codes, such as TRAC and COMMIX, do not have the capability to capture the stratification effect, due to strong numerical diffusion which smears away the hot/cold fluid interface. A related problem with standard codes is the inability to track plumes injected into the liquid flow, again due to numerical diffusion. The combined effects of buoyant stratification and plume dispersion have been identified as being important in operation of the Supplementary Safety System which injects neutron-poison ink into SRS reactors to provide safe shutdown in the event of safety rod failure. The MODFLOW code discussed here provides transient moderator flow pattern information with stratification effects, and tracks the location of ink plumes in the reactor. The code, written in Fortran, is compiled for Macintosh II computers, and includes subroutines for interactive control and graphical output. Removing the graphics capabilities, the code can also be compiled on other computers. With graphics, in addition to the capability to perform safety related computations, MODFLOW also provides an easy tool for becoming familiar with flow distributions in SRS reactors.},
doi = {10.2172/7368609},
url = {https://www.osti.gov/biblio/7368609}, journal = {},
number = ,
volume = ,
place = {United States},
year = {1992},
month = {3}
}