Optimization of reactor size in the small sodium-cooled CANDLE burning reactor

摘要

In this study, a sodium-cooled CANDLE burning reactor was optimized to minimize the reactor's size while maintaining its power. This study proved that with better heat-removal features of sodium coolant, it was feasible to reduce fuel pin pitch from 1.08 cm to 1.02 cm from a thermal hydraulics standpoint. We found that with the minimized fuel pin pitch, the critical core radius could be reduced by 19.4%, from 170.4 cm to 137.4 cm. Changing the radial reflectors from sodium to lead-based materials reduced the radius of the critical core and reflector 15.7%, from 187.4 cm to 158.0 cm. With these optimizations, a small sodium-cooled CANDLE burning reactor was designed with a core and reflector radius comparable to those of other small sodium fast-reactor concepts. The core height of the CANDLE burning reactor could be optimized by shortening the spent fuel region of the core. (C) 2020 Elsevier Ltd. All rights reserved.