ANALYSIS OF THE BEAVRS BENCHMARK USING CASMO5/SIMULATE5 WITH JENDL-4.0 AND ENDF/B-VII.1

Fujita Tatsuya,Sakai Tomohiro,M Margulis,P Blaise

doi:10.1051/epjconf/202124702014

Abstract

The BEAVRS benchmark was analyzed using the CASMO5/SIMULATE5 in order to compare the measurement data and the calculation results based on the JENDL-4.0 and ENDF/B-VII.1 and investigate the difference between those calculation results. For the hot zero power (HZP) physics test, the calculation results showed good agreement with the measurement data for both of cycles 1 and 2. For cycle 1, the calculation results of the isothermal temperature coefficient (ITC) differed from the measurement data by approximately 1 pcm/℉, and the same tendency has been reported in previous studies. For the cycle operation, the calculation results of the boron letdown agreed well with the measurement data. On the other hand, some calculation results of the axial detector signals had a large difference from the measurement data, which is supposedly attributed to the discrepancy of the axial offset (AO) caused by the authors’ approximation for the control rod and shutdown bank positions. In terms of the comparison between the JENDL-4.0 and ENDF/B-VII.1, although approximately 15 ppm difference of the boron letdown in the cycle operation was observed, no significant difference was seen for other core parameters, thus, the influence of the two nuclear data library was small on the present results.

Highlights

The CASMO5/SIMULATE5 [1,2], which is developed by Studsvik Scandpower, Inc., has been utilized in the Regulatory Standard and Research Department, the Secretariat of Nuclear Regulation Authority (S/NRA/R) in order to simulate the core characteristics of a light-water reactor (LWR) during normal operation and to calculate several important parameters, including the reactivity and peaking factor of a core.The Massachusetts Institute of Technology (MIT) computational reactor physics group proposed the Benchmark for Evaluation and Validation of Reactor Simulations (BEAVRS) [3]
The calculation results of the critical boron concentration (CBC), control rod bank worth (CRBW), and isothermal temperature coefficient (ITC) are summarized in Table II [3]
Compared with the cycle 1 results presented in Table II, the differences between the JENDL-4.0 and ENDF/B-VII.1 calculation results became slightly large, which would be due to the difference of spent fuel assembly condition at the cycle 1 end of cycle (EOC)

Summary

INTRODUCTION

The CASMO5/SIMULATE5 [1,2], which is developed by Studsvik Scandpower, Inc., has been utilized in the Regulatory Standard and Research Department, the Secretariat of Nuclear Regulation Authority (S/NRA/R) in order to simulate the core characteristics of a light-water reactor (LWR) during normal operation and to calculate several important parameters, including the reactivity and peaking factor of a core. In addition to such nominal calculations, the uncertainty has been analyzed based on the random sampling method [10,12]. For the HZP physics test, the critical boron concentration (CBC), control rod bank worth (CRBW), and isothermal temperature coefficient (ITC) were estimated, and for the cycle operation, the CBC and radial/axial detector signal distributions are estimated in this paper

CALCULATION MODEL

Results

CONCLUSIONS