Calculation of flow heat transfer characteristics of liquid gallium

Abstract In order to design a more compact small nuclear reactor, liquid metal gallium can be selected as the reactor coolant. Gallium is rarely used in reactor as liquid metal coolant, however, due to its excellent thermal conductivity and low melting point, research on the flow and heat transfer characteristics of liquid metal gallium in channels can provide a theory basis for nuclear reactor design optimization and relax reactor safety limits. The flow heat transfer characteristics of liquid gallium are obtained by calculating the surface heat transfer coefficient of liquid gallium in various thermal and structural parameters. The calculation results show that the heat transfer between liquid gallium and the pipe wall can be enhanced by the increase of the inlet flow velocity, the increase of the wall heat flux density, or the reduction of the pipe size. When the hydraulic diameter of each pipe is the same, the heat exchange effect of liquid gallium flow in tubes is: triangle tube>square tube>round tube. The flow heat exchange effect of liquid gallium is better than that of lead-bismuth fluid.