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Title: Analysis of nuclear reactor instability phenomena

Abstract

The phenomena known as density-wave instability often occurs in phase change systems, such as boiling water nuclear reactors (BWRS). Our current understanding of density-wave oscillations is in fairly good shape for linear phenomena (eg, the onset of instabilities) but is not very advanced for non-linear phenomena [Lahey and Podowski, 1989]. In particular, limit cycle and chaotic instability modes are not well understood in boiling systems such as current and advanced generation BWRs (eg, SBWR). In particular, the SBWR relies on natural circulation and is thus inherently prone to problems with density-wave instabilities. The purpose of this research is to develop a quantitative understanding of nonlinear nuclear-coupled density-wave instability phenomena in BWRS. This research builds on the work of Achard et al [1985] and Clausse et al [1991] who showed, respectively, that Hopf bifurcations and chaotic oscillations may occur in boiling systems.

Authors:
Publication Date:
Research Org.:
Rensselaer Polytechnic Inst., Troy, NY (United States)
Sponsoring Org.:
DOE; USDOE, Washington, DC (United States)
OSTI Identifier:
6641128
Alternate Identifier(s):
OSTI ID: 6641128; Legacy ID: DE93009397
Report Number(s):
DOE/ER/75701-1
ON: DE93009397
DOE Contract Number:
FG02-92ER75701
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; BWR TYPE REACTORS; REACTOR STABILITY; CALCULATION METHODS; HEAT TRANSFER; HYDRAULICS; MATHEMATICAL MODELS; OSCILLATIONS; PROGRESS REPORT; REACTOR KINETICS; THERMAL ANALYSIS; DOCUMENT TYPES; ENERGY TRANSFER; ENRICHED URANIUM REACTORS; FLUID MECHANICS; KINETICS; MECHANICS; POWER REACTORS; REACTORS; STABILITY; THERMAL REACTORS; WATER COOLED REACTORS; WATER MODERATED REACTORS 210100* -- Power Reactors, Nonbreeding, Light-Water Moderated, Boiling Water Cooled

Citation Formats

Lahey, R.T. Jr. Analysis of nuclear reactor instability phenomena. United States: N. p., 1993. Web. doi:10.2172/6641128.
Lahey, R.T. Jr. Analysis of nuclear reactor instability phenomena. United States. doi:10.2172/6641128.
Lahey, R.T. Jr. Fri . "Analysis of nuclear reactor instability phenomena". United States. doi:10.2172/6641128. https://www.osti.gov/servlets/purl/6641128.
@article{osti_6641128,
title = {Analysis of nuclear reactor instability phenomena},
author = {Lahey, R.T. Jr.},
abstractNote = {The phenomena known as density-wave instability often occurs in phase change systems, such as boiling water nuclear reactors (BWRS). Our current understanding of density-wave oscillations is in fairly good shape for linear phenomena (eg, the onset of instabilities) but is not very advanced for non-linear phenomena [Lahey and Podowski, 1989]. In particular, limit cycle and chaotic instability modes are not well understood in boiling systems such as current and advanced generation BWRs (eg, SBWR). In particular, the SBWR relies on natural circulation and is thus inherently prone to problems with density-wave instabilities. The purpose of this research is to develop a quantitative understanding of nonlinear nuclear-coupled density-wave instability phenomena in BWRS. This research builds on the work of Achard et al [1985] and Clausse et al [1991] who showed, respectively, that Hopf bifurcations and chaotic oscillations may occur in boiling systems.},
doi = {10.2172/6641128},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1993},
month = {Fri Jan 01 00:00:00 EST 1993}
}

Technical Report:

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  • The phenomena known as density-wave instability often occurs in phase change systems, such as boiling water nuclear reactors (BWRS). Our current understanding of density-wave oscillations is in fairly good shape for linear phenomena (eg, the onset of instabilities) but is not very advanced for non-linear phenomena [Lahey and Podowski, 1989]. In particular, limit cycle and chaotic instability modes are not well understood in boiling systems such as current and advanced generation BWRs (eg, SBWR). In particular, the SBWR relies on natural circulation and is thus inherently prone to problems with density-wave instabilities. The purpose of this research is to developmore » a quantitative understanding of nonlinear nuclear-coupled density-wave instability phenomena in BWRS. This research builds on the work of Achard et al [1985] and Clausse et al [1991] who showed, respectively, that Hopf bifurcations and chaotic oscillations may occur in boiling systems.« less
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  • The traveler visited Kernforschungszentrum Karlsruhe (KFK), Federal Republic of Germany (FRG) to confer with Dr. H.K. Stamm and other staff members to accomplish several objectives that relate to the computational analysis of dynamic crack run-arrest phenomena in reactor implementation which is the product of approximately three years of KFK work in the area of unified constitutive theories for rate-dependent materials. In exchange, the traveler would discuss with KFK a computer implementation of five elastic and inelastic candidate fracture parameters utilized in the ORNL ADINA computer program for elasto-dynamic and viscoplastic-dynamic fracture analysis. An essential feature of this exchange would bemore » in-depth discussions with the KFK staff concerning implementation, application, and future development of these computational techniques.« less
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