快堆物理计算程序NECP-SARAX1.0开发

Development of NECP-SARAX1.0 Code for Fast Reactor Physics Calculation

针对快堆物理特点,提出一套用于快堆堆芯核设计和稳态分析的计算程序NECP-SARAX1.0。程序采用基于ENDF/BVII的连续能量数据库,利用OPENMC程序产生多群截面,堆芯计算采用非结构网格进行几何建模,采用SN节块输运方法以同时满足临界和次临界堆芯的计算需求,采用微扰方法计算堆芯多普勒系数。数值验证表明,该程序具有较高的计算精度,与蒙特卡洛(MCNP)直接计算相比,有效增殖系数(keff)偏差在100×10-5左右。

A new code NECP-SARAX1.0 is developed for the nuclear design and steady analysis of the fast reactor core based on the special features of fast reactor physics. The continuous energy cross section library from ENDF/BVII is used. The OPENMC code is adopted to generate the multi-group cross sections. The SN-nodal method transport is applied in the core calculation based on the unstructured mesh modeling. It is suitable for both the critical and subcritical core calculation. The perturbation method is used to calculate the Doppler coefficients. Numerical results show that the new code is of high precision. Compared with direct MCNP calculation, the difference of keff is around 100×10-5.