由于反应堆堆芯存在大量重复结构,本文研究采用边界流响应矩阵的组件等效方法处理这些复杂结构。为使组件表面入射流J+与表面出射流J-的耦合关系为线性关系,将组件的裂变截面除以堆芯的keff,将堆芯物理计算的本征值问题转化为一固定源问题,这样只需得到J+与J-之间的线性耦合系数即可确定二者的耦合关系。然后通过在全堆芯范围内进行迭代,求出堆芯的keff及各组件的表面流,进而得到堆芯各处的通量分布形状。采用二维SN程序SN2D,对C5G7基准题的等效误差进行计算分析。结果表明:在不进行能群和角度归并的情况下,采用该方法可得到较为精确的keff及组件功率,但栅元功率分布仍存在一定误差,需在进一步研究中加以解决。
There are many repetition structures in nuclear reactor cores,so the equivalent homogenization method was investigated.In order to make the linear relationship between the inflow and the outflow of the assembly boundary,the fission cross sections were divided by the keff of the reactor core,thus the eigen-value problem was transformed into a fixed source problem.As a result,the coupling correlation of J+ and J-could be decided by the linear coupling coefficients of them.Through iteration calculation in the reactor core,the keff of the reactor core and the boundary flows of every assembly could be worked out,and then the flux distribution was got.The C5G7 benchmark equivalent error was calculated and analyzed by using two dimensional SN program SN2D.The results show that this method can get better keff and assembly power without group and angle merging,but the precision for pin power still needs to be improved in further studies.