Experimental research on heat transfer characteristic of liquid lead-bismuth eutectic flowing in annular channel

Liquid lead-bismuth eutectic(LBE) has been studied as a new type of coolant for an accelerator driven sub-critical system (ADS). And the gas-lift pump has been used to enhance the circulation capacity of coolant in ADS instead of mechanical pumps due to its simpler mechanical structure and higher security. The purpose of this experiment is to study the circulation capacity enhancement by gas-lift technique and the flow and heat transfer characteristic of liquid LBE in an annular channel. The experimental results show that: gas-injection can significantly increase liquid LBE mass flow rate, but the growth of liquid LBE mass flow rate will be reduced when gas flow rate reaches a value; The friction coefficient of liquid LBE in an annular channel decreases with the increase of Re and is larger than that calculated by Blasius formula at the same Re. For the convection heat transfer of liquid LBE in an annular channel, the heat conduction term is dominant, and Nusselt number increases with the increase of Peclet number. The experimental correlations of friction coefficient and convection heat transfer of liquid LBE in annular channel were fitted based on experimental data and compared with those from literature.