Application of the neutron-photon-electron coupling transport of cosRMC in fusion neutronics

Abstract When evaluating the radiation field of fusion reactors, the transport and interaction of neutrons, photons and electrons should be considered. The neutron-photon-electron coupling transport capability was developed in Monte Carlo code cosRMC. Based on this feature, the neutron-photon-electron coupling transport simulations were applied to the neutronics calculation of fusion reactors using cosRMC. Firstly, the correctness of neutron-photon-electron coupling transport capability of cosRMC was verified by the spherical shell model and the fuel assembly model. The coupling transport capability was then applied to the neutronics calculation of the China Fusion Engineering Experimental Reactor (CFETR) model. Three different treatments for electron including neglection of electrons, thick-target bremsstrahlung approximation and explicit electrons transport were compared, to investigate their accuracy and efficiency for the calculations of photon flux and nuclear heat deposition. The results showed that, considering the balance between accuracy and efficiency, the thick target bremsstrahlung approximation was the best choice for the nuclear heat deposition of fusion reactors.