Safety Enhancement in the Molten Salt Fast Reactor (MSFR)

Abstract

: This study presents a new modification for the cooling circuit design of the Molten Salt Fast Reactor MSFR to solve the problem of high temperatures in the hot spots regions that affect the reactor safety. These high temperature regions appear as a result of the salt recirculation of the liquid fuel. This problem causes a decrease in the delayed neutron fraction value β eff. . This decrease in β eff. reduces the safety of the reactor because it shifts it more close to the prompt critical state. The new modification depends on distributing the flow between the side and the centre by adding a coolant circuit passes through the core centre from the bottom to the top. At the end of this study we see that this new design moderated the hot spots and reduced the maximum temperature to about 1120 k. This value is greater than the core outlet temperature by about 77 k and smaller than the maximum temperature of the benchmark design by about 160 k. The design also reduced the salt velocity from the benchmark value 3.9 m/s to the value 2.38 m/s.