Modeling and criticality calculation of the Molten Salt Fast Reactor using Serpent code

Abstract

In Molten Salt Fast Reactors (MSFR), a liquid-fuel circulates through the cylinder core and transport the fission heat to the Intermediate external Heat Exchangers (IHX), therefore liquid salt allows carrying the fuel and transfer heat. The MSFR supposed to work in a closed Th-based fuel cycle with a full reprocessing of fission products and all actinides in the core. The aim of this paper is; modeling the primary circuit of the MSFR (based on the European model) in order to identify the composition of the start-up fuel required to the criticality. In conclusion, the compositions of the start-up liquid fuel required for criticality and long life cycle were determined precisely for three different types of fissile materials (233UF4, PuF3 and TRUF3).