CEFR探测器三维空间响应函数敏感性研究

本文利用离散纵标程序研究了网格划分、能群数目、角度离散数和散射截面展开阶数等计算条件对堆芯区域共轭中子注量率分布形状的影响。基于求解共轭输运方程计算了中国实验快堆钠池内探测器三维空间响应函数，分析了控制棒位置、燃耗累积、燃料组件装载等因素对探测器空间响应函数的影响。结果表明：共轭中子注量率分布形状对网格宽度的敏感性低，可利用粗网格条件下共轭中子注量率分布形状求解探测器空间响应函数；控制棒对空间响应函数的影响与控制棒在堆芯中所处位置有关，组件内空间响应函数受控制棒影响程度与组件和控制棒的相对位置有关；探测器空间响应函数受新装载组件影响较明显，但对新装载组件位置的敏感性低。本文结果为大型快堆探测器空间响应函数计算提供了参考，为快堆动态刻棒提供了技术支持。

Sensitivity Analysis of 3D Space Response Function of Detector of CEFR

The effect of calculation conditions, such as grid division, number of energy groups, number of angles and expansion order of scattering cross section, on the shape of adjoint neutron fluence rate was studied using a discrete ordinate code. By solving the adjoint transport equation, the 3D spatial response function (SRF)of the detector in China Experimental Fast Reactor was calculated. The effects of position of control rod, fuel burnup, number of fuel subassemblies loaded on the SRF were analyzed. The results show that shape of adjoint neutron fluence rate has low sensitivity to the grid width, and under a coarse grid condition it can be used to calculate SRF. The influence of the control rod on SRF is related to the position of the control rod in the core, and the degree at which SRF is affected by the control rod is related to the relative positions of the fuel subassemblies and the control rod. The SRF is obviously affected by the newly loaded fuel subassemblies, but the sensitivity between the SRF and the position of newly fuel loaded subassemblies is low. The results provide a reference for the calculation of SRF, and technical support for dynamic rod worth measurement in large fast reactors.