Preliminary assessments of carbide fuel pins during mild overpower transients in LMFBRs

Abstract

Mixed carbide fuel has been proposed for advanced liquid metal fast breeder reactors (LMFBRs). In this paper the general characteristics of carbide fuel are reviewed and a survey of available data for use in safety studies is presented. A preliminary investigation of the unprotected transient overpower accident sequence postulated for a large carbide fueled reactor is also presented. The HOPE computer code is the computational tool used to analyse a conceptual core design fueled with mixed carbides of uranium and plutonium. The details of this design are presented and compared with those of the Clinch River Breeder Reactor Plant. Results of HOPE calculations for both helium and sodium bonded carbide fueled cores are presented and compared with a similar study performed on an oxide core. Conclusions are drawn based on the findings of the preliminary transient overpower studies conducted.