第二类边界条件先进格林函数节块法

目前广泛应用的节块格林函数法是基于第三类边界条件，这类格林函数比较复杂，并且不便直接使用不连续因子，必须经过转换后才能使用和功率重构。该文发展了第二类边界条件三维几何先进格林函数节块法。该方法的优点是格林函数计算较简单，便于在交界面处引入通量不连续因子，并通过功率重构得出堆芯内精细通量分布。基准计算表明，该程序精度高、速度快，成为水堆堆芯物理设计和燃料管理计算的核心程序。

Advanced nodal Green's function method on Neumann boundary condition

The presently broadly used code of nodal Green's function method for multidimensional neutron diffusion calculations is based on the third kind boundary condition. the form of this kind Green's function is relatively complex, and it must be converted so that the discontinuity factors can be used and the core power can be reconstructed. An advanced nodal Green's function method for three dimensional geometry which is based on the Neumenn (second kind) boundary condition was developed. Advantages of the method are: a) the Green's fuction is simplfed; b) it is easy to use discontinuity factors in the continuity condition of interface partial flux, and the fine flux distribution in the assembly is obtained by pin power reconstruction. the code NNGFM which is based on present method shows higher speed and accuracy through actual computation. It becomes the kernel code in the light water reactor (LWR) physics design and nuclear fuel management calculations.