中文摘要：

栅元模块化特征线方法（MOC）在处理压水堆组件水隙等问题上存在几何处理上的困难。为了克服这些问题,采用Fortran语言开发了基于组件模块化特征线方法（AMRT）的中子输运计算程序NECP-Medlar,并采用两重粗网有限差分方法进行加速。2D C5G7基准题和典型压水堆组件问题的数值计算结果表明,该程序具有良好的计算精度和较高的计算效率,并且能够通过直接计算组件之间的水隙,较精确地描述组件中子通量密度的分布。

英文摘要：

it is difficulty for the MOC method based on Cell Modular Ray Tracing to deal with the irregular geometry such as the water gap between the PWR lattices. Hence, the neutron transport code NECP-Medlar based on Assembly Modular Ray Tracing is developed. CMFD method is used to accelerate the transport calculation. The numerical results of the 2D C5G7 benchmark and typical PWR lattice prove that NECP-Medlar has an excellent performance in terms of accuracy and efficiency. Besides, NECP-Medlar can describe clearly the flux distribution of the lattice with water