Study on Pin Power Reconstruction Method Based on 3-D Multi-Group Analytic Nodal Method for Hexagonal-z Geometry

Based on the theory that the hexagonal intra-nodal flux distribution can be expanded to a 3D-form in a series of analytic basic functions for each group,the analytic function expansion nodal method can be directly used for pin power reconstruction.Based on the proposed model,a module of pin power reconstruction has been developed for HANDF-E code.Compared with Monte Carlo code MCMG,the numerical results of VVER-440 benchmark and 3-D four-group thermal reactor benchmark show that HANDF-E can predict accurately the pin powers.