Nuclear Techniques ›› 2014, Vol. 37 ›› Issue (09): 90606-090606.doi: 10.11889/j.0253-3219.2014.hjs.37.090606


Study on ASTRUM optimization for large break LOCA analysis

YU Jianhui ZHANG Jingyu ZHENG Limin   

  1. (Shanghai Nuclear Engineering Research & Design Institute, Shanghai 200233, China)
  • Received:2014-04-30 Revised:2014-06-15 Online:2014-09-10 Published:2014-09-09

Abstract: Background: The ASTRUM (Automated Statistical Treatment of Uncertainty Method) methodology is developed by Westinghouse. In this method, some important parameters for large break loss of coolant accident (LBLOCA) analysis are treated conservatively to get a conservative set, which is called confirmatory study. And the value set of parameters is then used to generate the reference transient input deck of ASTRUM calculation. The value set may be varied in different sampling cases. However, the ASTRUM is executed based on one value set of some parameters, although other parameters are sampled. The result of the ASTRUM calculation may be not very exact. Purpose: The aim of this study is to reduce the uncertainty and conservatism, and optimize the ASTRUM. Methods: The parameters concerned in the confirmatory study of ASTRUM were sampled by BE_SAMPLE code developed by this paper for each ASTRUM case. The optimized ASTRUM is executed in company with other sampled parameters. Results: The results of the original and optimized ASTRUM calculations are compared, and the peak cladding temperature (PCT) calculated by new ASTRUM is lower than the original result. Conclusion: The study on ASTRUM optimization reduces the uncertainty caused by confirmatory study, which makes the ASTRUM calculation much more precise.

Key words: Large break loss of coolant accident (LBLOCA), Best estimate (BE), ASTRUM (Automated Statistical TReatment of Uncertainty Method)