Thermal hydraulic analysis of the thorium-based advanced CANDU Reactor fuel channel

This paper presents a thermal hydraulic analysis of the thorium-based advanced CANDU Reactor (TACR-1300) fuel channel. The paper first uses CATHENA, a system thermal hydraulics code for CANDU reactors, to determine the boundary conditions of the TACR-1300 fuel channel. The boundary conditions are then passed to ASSERT-PV, a subchannel thermal hydraulics code for the CANDU industry, to obtain detailed thermal hydraulic information on the TACR-1300 fuel channel. Through the subchannel analysis, it is found that the onset of dry-out power (ODP) for the TACR fresh fuel channel is much less than that of the ACR-700 because thorium fuel rods as well as uranium rods are not heated and there is bypass-flow effect in the associated subchannels. The paper compares three thorium loading modes, and determines the best one for TACR.