Study on core physical parameters for molten salt experimental reactor

[Background] Molten salt reactor (MSR) adopts molten fluoride salt mixture as fuel. The neutronic features of MSR are different from those of traditional solid-fuel reactors duel to specific nuclear fuels. [Purpose] This study aims at the effects of core parameters on reactor physics of MSR. Parameters include core size, fuel volume fraction, fuel concentration, fuel salt penetration and so on. [Methods] Molten-salt reactor experiment (MSRE) of Oak ridge national laboratory (ORNL) was taken as the reference reactor and the calculation was completed by using MCNP (Monte Carlo N particle transport code). [Results] The calculation results show that with the increase of core size, the critical mass of core has a minimum value. With the increase of fuel volume fraction, the critical mass of fuel salt loop system first decreases and then increases, and the absolute value of fuel temperature coefficient decreases firstly and then increases. The effect of fuel salt penetration on core reactivity is consistent with that fuel volume fraction increment. [Conclusions] This study provides basic theoretical reference for the design of thorium molten salt reactor-liquid fuel (TMSR-LF1). (authors)