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Title: Flux stability and power control in the Soviet RBMK-1000 reactors

Abstract

As a result of the Chernobyl accident, the Soviets have studied and implemented various design changes to improve the safety of the RBMK reactors. The safety measurements include modifications of the control rod configuration, fuel enrichment increase from 2.0 to 2.4 weight percent U-235, and installation of additional supplemental absorbers. The purpose of this study is to investigate the effects of increased fuel enrichment, different control rod positions, and supplemental absorber loadings on reactivity control, power distribution within the large RBMK core, and relative stability against power oscillations.

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest Lab., Richland, WA (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
10189355
Report Number(s):
PNL-8781
ON: DE94000546; TRN: 93:022997
DOE Contract Number:
AC06-76RL01830
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Aug 1993
Country of Publication:
United States
Language:
English
Subject:
22 GENERAL STUDIES OF NUCLEAR REACTORS; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; LWGR TYPE REACTORS; REACTOR CONTROL SYSTEMS; MODIFICATIONS; REACTOR SAFETY; NUCLEAR FUELS; NEUTRON ABSORBERS; REACTIVITY; POWER DISTRIBUTION; EXCURSIONS; XENON OSCILLATIONS; STABILITY; 220400; 220900; 210300; CONTROL SYSTEMS; POWER REACTORS, NONBREEDING, GRAPHITE MODERATED

Citation Formats

Meriwether, G.H., and McNeece, J.P.. Flux stability and power control in the Soviet RBMK-1000 reactors. United States: N. p., 1993. Web. doi:10.2172/10189355.
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Meriwether, G.H., & McNeece, J.P.. Flux stability and power control in the Soviet RBMK-1000 reactors. United States. doi:10.2172/10189355.
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Meriwether, G.H., and McNeece, J.P.. Sun . "Flux stability and power control in the Soviet RBMK-1000 reactors". United States. doi:10.2172/10189355. https://www.osti.gov/servlets/purl/10189355.
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@article{osti_10189355,
title = {Flux stability and power control in the Soviet RBMK-1000 reactors},
author = {Meriwether, G.H. and McNeece, J.P.},
abstractNote = {As a result of the Chernobyl accident, the Soviets have studied and implemented various design changes to improve the safety of the RBMK reactors. The safety measurements include modifications of the control rod configuration, fuel enrichment increase from 2.0 to 2.4 weight percent U-235, and installation of additional supplemental absorbers. The purpose of this study is to investigate the effects of increased fuel enrichment, different control rod positions, and supplemental absorber loadings on reactivity control, power distribution within the large RBMK core, and relative stability against power oscillations.},
doi = {10.2172/10189355},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Aug 01 00:00:00 EDT 1993},
month = {Sun Aug 01 00:00:00 EDT 1993}
}
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Technical Report:
View Technical Report (5.84 MB)
DOI:  10.2172/10189355
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  • ; ; - Nuclear Technology; (United States)
    This paper reports on a coupled thermal- hydraulic analysis that is performed for the Soviet-designed RBMK-1000 nuclear power reactor to assess the operating margin to critical heat flux (CHF); the Chernobyl-4 reactor serves as the principal model for this study. Calculations are performed using a simplified subchannel analysis. The overall analysis involves an iterative search to determine the individual subchannel flow rates, and a boiling transition analysis is performed to obtain a measure of the core operating margin. The operating margin is determined via two distinct methods. The first involves a calculation of the core critical power ratio (CPR) usingmore » an empirically derived correlation that the Soviets developed expressly for the RBMK-1000. Additionally, various subchannel CHF correlations typical of those used in the design of nuclear-powered reactors in the United States are also employed. When the Soviet critical power correlation is used, the calculations carried out for both normal operating and reference overpower conditions result in CPRs of 1.115 and 1.019, respectively. In most cases, the subchannel CHF correlations indicate that additional operating margin over that calculated by the Soviet critical power correlation exists for this design.« less

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  • ;
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