三维离散纵标-蒙特卡罗耦合方法在快中子注量率计算中的应用

Application of Three-Dimensional Discrete Ordinatesand Monte Carlo Coupling Method on Fast Neutron Fluence Rate Calculation

采用三维离散纵标-蒙特卡罗耦合方法(SN-MC耦合方法)对压水堆压力容器的快中子注量率进行计算分析,并与离散纵标方法(SN方法)、蒙特卡罗方法(MC方法)的计算结果以及测量值进行比较。结果表明,SN-MC耦合方法的计算结果和测量值相比偏差在20%以内,满足美国核管会(NRC)法规导则RG1.19对快中子注量率计算方法偏差的要求;当SN-MC耦合方法和MC方法达到相同计数误差水平时,其计算速度比MC方法快2~10倍。

A three-dimensional discrete ordinates and Monte Carlo coupling method(the SN-MC coupling method) is applied on Pressurized Water Reactor(PWR) pressure vessel Fast Neutron Fluence rate(FNF) calculation, and the results of the SN-MC coupling method are compared with those of the discrete ordinates method(the SN method), the Monte Carlo method(the MC method) and the measurements. Numerical results show that the difference between the calculated FNF by the SN-MC coupling method and the measured FNF are less than 20%, which satisfies the requirement of the difference for FNF calculated methods in Regulatory Guide(RG) 1.19 promulgated by Nuclear Regulatory Commission(NRC). The speed of the SN-MC coupling method is 2~10 times faster than that of the MC method when the two methods obtain the same tally errors.