KYCORE程序中子输运计算的改进

Improvement in Neutron Transport of KYCORE Code

KYCORE程序是在中国核动力研究设计院开发的二维组件计算程序KYLIN-2基础上开发的三维堆芯数值计算程序,其中中子输运部分采用径向特征线方法(MOC)与轴向离散坐标法(SN)直接角通量耦合的方法实现高精度计算,并通过粗网有限差分方法(CMFD)加速实现快速收敛。KYCORE程序因为计算流程的简化,导致可能出现不收敛,因此在计算方法和网格划分上做了改进,提高了计算的稳定性和包容性。通过与C5G7扩展基准题和蒙特卡罗程序的计算对比,数值验证了KYCORE输运部分计算的稳定性与准确性。

KYCORE is a 3 D nuclear reactor numerical calculation software and it is developed from KYLIN-2, a 2 D assembly calculation software developed in Nuclear Power Institute of China. The neutron transport part uses 2 D MOC and 1 D SN coupling to realize high precision through direct angular flux coupling and is accelerated with coarse mesh finite difference(CMFD). Due to the simplification in the calculation procedure, the KYCORE code may detergency in calculation, thus it is improved in calculation method and mesh dividing. The salability and accuracy of the KYCORE 3 D neutron transport calculation are verified with the comparison to Monte Carlo code and C5 G7 extension case.