Optimization of a DRACS Decay Heat Removal System for the Fluoride Salt-cooled High Temperature Reactor (FHR) Using a Novel Directional Heat Exchanger

摘要

The Fluoride salt-cooled High-temperature Reactor (FHR) is a class of reactor concepts currently under development for the U. S. Department of Energy. The FHR is defined as a Generation IV reactor that features low-pressure liquid fluoride salt cooling, coated-particle fuel, a high-temperature power cycle, and fully passive decay heat rejection. The current FHR baseline design has adopted the Direct Reactor Air Cooling System (DRACS) originally demonstrated in the Experimental Breeder Reactor-II (EBR-II) and utilized in a variety of Sodium Fast Reactor (SFR) designs. The DRACS system is fully passive and removes decay heat via natural circulation. The performance of the DRACS Heat Exchanger (DHX) is a critical element of the DRACS performance and the overall FHR safety case. In this paper, a conceptual design for a directional DHX is presented where an experimental validation program is proposed.