Review of Existing Codes for Loss-of-Coolant Accident Analysis

  • Stanislav Fabic
Part of the Advances in Nuclear Science and Technology book series (volume 10)


Within the last two years it has become customary in the United States to categorize all LOCA codes into two main groupings: the codes employed in the licensing application which obey the conservative assumptions prescribed by the NRC Acceptance Criteria described in Appendix K to 10 CFR 100 (1). These codes employ the so-called Evaluation Model and are generally referred to as the EM codes. The WREM package includes most of the EM codes necessary for the safety evaluation of the Water Reactors performed independently by USNRC. The second grouping consists of the so-called Best Estimate (BE) codes which employ models that are not conservative, but instead, represent a realistic representation of the physical processes. Some of the existing BE codes, such as RELAP-4 Mod 5 (developed by the Aerojet Nuclear Company for USNRC) are simply structured. Advanced BE codes now under development incorporate the present state of the art in both the modeling and the numerical analysis treatment. The present EM codes comprise an assembly of codes run sequentially. Each member of the sequence is a stand-alone code developed for some special application.


Critical Heat Flux Break Flow Pressurize Water Reactor Component Code Accident Analysis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Press, New York 1977

Authors and Affiliations

  • Stanislav Fabic
    • 1
  1. 1.Analysis Development Branch, Water Reactor Safety ResearchU. S. Nuclear Regulatory CommissionUSA

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