Effect of core configuration on natural convection and heat transfer in heat pipe cooled micro-MSRs

Heat pipes are used to remove the nuclear heat of liquid fuel salt in heat pipe cooled micro molten salt reactors (micro-MSRs). The natural convection and heat transfer of fuel salt are influenced by the core configuration. This paper used the ANSYS to simulate the natural convection in a horizontal reactor core with heat pipes arranged in triangular and concentric circular layouts of 0 degrees and +/- 30 degrees, which can obtain the temperature distribution and heat transfer characteristics of the reactor core and optimize the core design. Also, the influence of the number and diameter of heat pipes were analyzed in this paper. It shows that the temperature distribution under tilt conditions in heat pipes with a concentric circular layout is more uniform and stable than that with a triangular layout. Moreover, stronger heat transfer capacity and more uniform temperature distribution were obtained with denser heat pipes under the same cross-sectional area. Therefore, a concentric circular layout of heat pipes should be adopted in designing the heat pipe cooled micro-MSRs.