Validation of SARAX Code System Using Phenix Control Rod Withdrawal End-of-Life Experiments

The Phenix control rod withdrawal end-of-life experiment is the last reactor measurement test before the decommissioning of Phenix rector, a French sodium cooled reactor. In the experiments, the value of control rod worth under low power and the radial power distribution in full power state were measured. Through the modeling and calculation of the experiment using SARAX, a sub-computational program system for the fast reactor developed by Xi’an Jiaotong University, the accuracy of the SARAX program system in the physical calculation of the sodium-cooled MOX fuel fast reactor core can be confirmed. In the calculation, ultra-fine group and point-wise cross section were used for energy spectrum calculation, the super-homogeneous（SPH） factor were used for the assembly homogenization calculation, and the multi-group neutron transport nodal method were used for core calculation. The keff, control rods worth, core reactivity coefficient and power distributions were calculated at four critical states. The calculation results show that the results of SARAX are in good agreement with the experimental values, and the calculation accuracy is better than the traditional fast reactor physical calculation program, which can be used in the nuclear design of sodium-cooled fast reactor loaded with MOX fuel.