Research on decay heat removal effectiveness in pool-type fast reactor CEFR based on system code SAC-DRACS coupled with CFD software

In station blackout(SBO) accident, the establishment and maintenance of natural circulation in the China Experimental Fast Reactor(CEFR) mainly relies on the decay heat removal system(DHRS). However, due to the complex structure of the reactor, it's very difficult to model the full-scale CEFR. In the present work, DHRS and the primary circuit system of the CEFR are modeled by the System Analysis Code for Direct Reactor Auxiliary Cooling System (SAC-DRACS) code and three-dimensional CFD software FLUENT, respectively. Then the long-term transient simulation of 4000 s is calculated by coupling SAC-DRACS and CFD codes. The overall temper-ature stratification and local core temperature variations in the pool caused by DHRS are analyzed. Meanwhile, the residual heat removal capacity of DHRS is evaluated, the average core outlet temperature does not exceed 500.3 C under the action of DHRS. This work provides an extension of the research method for the pool-type fast reactor safety analysis.