Optimization study of pressurized water reactor secondary neutron source location

Abstract During the loading and refueling of Pressurized Water Reactor (PWR), Sb-Be secondary neutron source is generally used to induce fission reaction to increase ex-core detector signal, which could eliminate the monitoring blind area. In order to obtain the optimal position of secondary neutron source which would lead a maximum signal, it is necessary to evaluate the contribution of secondary neutron source at different potential positions. Based on CAP1400 PWR model, Discrete ordinate (SN) adjoint transport method has been studied by using 199 groups fine cross section. Fission source contribution is simulated by controlling outer iteration in adjoint transport calculation. The contribution of secondary neutron sources at different potential positions has been analyzed. Monte Carlo (MC) forward calculation has been used as a comparison, and the two results are in good agreement with each other. Through the analysis, secondary neutron source optimal location in reactor core can be obtained. The innovative method can provide a reference for the layout optimization of secondary neutron source.