Calculation and Analysis of DPA Rate in Core Can and Reactor Vessel of Molten Salt Reactor Experiment

The displacement-peratom (DPA) rates for the molten salt reactor experiment (MSRE) core can and reactor vessel were calculated and analyzed by the Monte Carlo program MCNP5 in this paper. The neutron fluence rate distributions in the core can and the reactor vessel were determined, and one of the biggest neutron fluence rate region DPA rate was calculated in detail. The results show that the maximum DPA rate happens on the inner surface of core can and reactor vessel, near the reactor mid plane, with θ between 22° to 34°and the maximum DPA value can be 3.90×10^-9s^-1 and fast neutrons make more contribution to DPA rate than thermal neutrons. The conclusion has important practical significance on the new concept molten salt reactor design and parameter selection.