介绍了中子输运蒙特卡罗方法与热工水力耦合计算的流程。开发了一套蒙卡中子输运程序JMCT和子通道分析程序COBRA-EN耦合接口。通过3×3棒束模型的计算展示了考虑耦合计算和不考虑耦合计算的差异,论证了耦合计算在反应堆分析中的重要性。通过对反应堆组件的模拟计算,测试了耦合计算的正确性。最后分析了蒙卡计算的统计涨落和迭代计算过程中收敛标准的关系,讨论了蒙卡中子输运和热工水力耦合过程中收敛标准设置的方案和可行性。

Coupled neutronics and thermal-hydraulics calculation can enhance the computational accuracy in reactor simulation. With the development of computational capability, the coupled Monte-Carlo neutron transportation and thermal-hydraulics calculation plays an important role in reactor core design and reactor safety. This paper gives a short introduction of the Monte Carlo code JMCT, the sub-channel code COBRA-EN and their coupling scheme. The coupled codes are applied on the 3×3 fuel bundles model and the UO2 assembly simulation. The calculated results are discussed, especially, the convergence criteria and quantification of correlation between statistical uncertainty and coupled error.