中文摘要：

从二阶自共轭角注量率（SAAF：Self-Adjoint Angular Flux）中子输运方程出发，在二维圆柱坐标系下利用球谐函数对角度变量进行展开，推导出了一组关于空间变量的偏微分方程组，然后采用有限元方法进行了空间离散，编写了二维圆柱坐标系下的球谐函数输运计算程序。对一系列例题进行校验的数值结果表明，该方法具有较高的计算精度，克服了射线效应。

英文摘要：

The spherical harmonics （PN） method is applied to a second order Self-Adjoint Angular Flux （SAAF） neutron transport equation in the two-dimensional cylindrical coordinates. The spherical harmonics functions are used to expand the angular flux. A set of differential equations about the spatial variables is derived. The spatial variables are discretized by means of the f＇mite element method. A computational code for multi-group neutron transport equation named TEPFEM-C is developed based on the present model. The numerical results of some benchmark problems demonstrate that this method can give high precision results and avoid the ray effect very well.