TPFAP——a Code Package for LWR Fuel Assembly Calculation
Zhang Zongyao Li Datu Yao Dong Cheng Heping (Nuclear Power Institute of China, Chengdu, 610041) Xie Zhongsheng Yin Banghua (Xi'an Jiaotong University, 710049)
TPFAP is a transmisssion probabilily fuel assembly code package for burnup calculations on BWR and PWR. The transport calculation is started with a number of micro-group calcula tions in the library structure by using of collision probability method in three or four annular regions. Effective absorption cross section generated by the CMB are used for Gd loaded fuel or boron pin cell. The 2D multi-group integral transport routine based on the transmission probability method is in (x, y) geometry. A fundamental mode calculation is performed to accouunt for leakage effect. The effective diffusion theory cross section are calculated using the reaction rate equivalence theorem. The depletion is calculated in each fuel and burnable absorbor pin. Then TPFAP output few group macro and micro cross section and power distribution at each burnup step for pin cell and assembly, being used in the nuclear design, fuel management and safely analysis.