The development of two-phase three-node model used to simulate the transport of ACPs

Activated corrosion products (ACPs) are the dominant radiation hazard in water-cooled fusion reactor under normal operation conditions, and directly determine the occupational radiation exposure during operation and maintenance. In this paper, a two-phase three-node model is set up, and code CATE V2.0 is developed. Compared to the two-phase homogeneous model used in CATE V1.0, it is capable to analyze the spatial distribution of the ACPs along the cooling loops, and has the ability to deal with pulse of neutron flux, and almost all the radionuclides produced in the loop can be simulated. In the paper, the LIM-OBB loop of ITER is simulated by CATE V2.0. Different pulse handling methods applied to the simulation are compared. The spatial distribution of the composition and activity of ACPs along the loop is presented. And then the dose rate of the LIM-OBB loop is calculated by point kernel code ARShield.