Thermal hydraulics analysis for modified sodium-to-sodium decay heat exchanger of CEFR

Decay heat removal system is one of principal engineered safety features of pool-type sodium-cooled fast reactor, it is a main way to carry out the safety function of decay heat remove under some accident conditions for the reactor, such as reactor scram condition, and one of the key equipment of decay heat removal system for fast reactor s sodium-to-sodium decay heat exchanger(DHX). We use the ANSYS FLUENT software to run transient numerical emulations of the DHX in CEFR and the new modified DHX which s setup in hot pool of fast reactor. Through comparing the emulation results the feasibility of the modified DHX design is demonstrated in terms of thermal hydraulics performance. The numerical analysis results are important reference to the design of DHX for large-type size fast reactor. (authors)