Benchmark calculations on control rod withdrawal tests performed during Phenix End-of-Life experiments

Phenix End-of-Life試験における制御棒引抜試験に対するベンチマーク解析

Pascal, V.*; Prulhire, G.*; Fontaine, B.*; Devan, K.*; Chellapandi, P.*; Kriventsev, V.*; Monti, S.*; Mikityuk, K.*; Semenov, M.*; Taiwo, T.*; 高野 和也 ; Tiberi, V.*

Pascal, V.*; Prulhire, G.*; Fontaine, B.*; Devan, K.*; Chellapandi, P.*; Kriventsev, V.*; Monti, S.*; Mikityuk, K.*; Semenov, M.*; Taiwo, T.*; Takano, Kazuya; Tiberi, V.*

2009年に仏Phenix炉のEnd-of-Life試験において、定格出力時における制御棒の非対称引抜が径方向出力分布に与える影響を把握することを目的とする「制御棒引抜試験」が実施された。IAEAのTWG-FR(高速炉技術作業部会)において本試験に対するベンチマーク解析を実施するための共同研究プロジェクト(CRP)が立ち上げられ、CEA, ANL, IGCAR, IPPE, IRSN, JAEA, KIT, PSIから専門家が参加し、本CRPを進めている。ここでは「制御棒引抜試験」の概要及び制御棒非対称引抜に伴う出力分布変化に対する測定結果について述べるとともに、本CRPにて得られた解析結果をもとに、測定結果との差及び解析結果同士の差の要因について考察する。

The control rod withdrawal test was one of the various Phenix End-of-Life tests performed in 2009. The main goal was to determine the impact of a rod insertion and/or extraction on the radial power distribution in the fissile core at nominal power. The framework of the Technical Working Group on Fast Reactors (TWG-FR) activities in IAEA, decided to launch a Coordinated Research Project (CRP), devoted to benchmarking analyses on the test. The CRP was performed by experts coming from CEA, ANL, IGCAR, IPPE, IRSN, JAEA, KIT and PSI. After a short description of the test conducted in the Phenix reactor, this paper presents some results obtained in the course of the CRP with special emphasis on control rod efficiencies and power deformation by subassemblies. The paper also discusses the discrepancies found when comparing calculated results with experimental data as well as some preliminary conclusions on the source of these discrepancies.