钴调节棒更换后RFSP-IST程序通量计算不确定性分析

在中核核电运行管理有限公司秦山第三核电厂（简称秦山三核）调节棒组件变更设计的物理分析中，用于堆芯计算程序RFSP-IST的钴调节棒增量截面由DRAGON产生，它的方法模型与秦山三核安全分析报告RFSAR（2007版）所采用的超栅元计算程序MULTICELL不完全相同，因此有必要对调节棒组件变更前后RFSP-IST程序通量计算不确定性进行分析。基于秦山三核1、2号机组的相关历史运行数据，采用95/95单边上限不确定性分析方法，对调节棒组件变更前后RFSP-IST程序通量计算不确定性进行分析。数值计算结果表明，调节棒组件变更设计及超栅元增量截面计算程序变更未对RFSP IST程序通量计算不确定性产生影响。

Uncertainty Analysis of RFSP-IST Code Flux Calculation After Cobalt Adjuster Rod Replacement

In physical analysis of the cobalt adjuster rods design change for Qinshan Phase Ⅲ, the incremental cross section used in RFSP-IST code for the cobalt adjuster rod was calculated by DRAGON, whose methodology was not exactly the same as the MULTICELL used for Qinshan Phase Ⅲ RFSAR (2007), hence it was necessary to do the uncertainty analysis for RFSP-IST code flux calculation after cobalt adjuster rod replacement. Based on the historical data from Unit 1 and Unit 2 of Qinshan Phase Ⅲ, the uncertainty analysis of RFSP-IST code flux calculation was done with 95/95 upper tolerance limit method. Numerical results show that the cobalt adjuster rod design change and different incremental cross section calculation codes do not impact the uncertainty of RFSP-IST code flux calculation.