The combination of supercritical carbon dioxide Brayton cycle and lead cooled fast reactor is considered as one of the most ideal power cycles. The system transfers heat through the intermediate heat exchanger

and its performance affects the efficient and safe operation of the whole power generation system. Due to the significant differences in physical properties and heat mass transport properties between supercritical carbon dioxide and liquid lead bismuth eutectic

the symmetrical structure cannot match the heat transfer requirements of the working fluids on both sides. In this study

an asymmetric compact coupled heat exchanger was constructed

and the coupled heat transfer characteristics of supercritical carbon dioxide and liquid lead bismuth eutectic were studied by numerical simulation. Increasing the inlet velocity of the cold side fluid will significantly enhance the heat transfer; When the inlet velocity of LBE at the hot side is increased

the total heat transfer coefficient first decreases and then increases;When the inlet temperature of the cold and hot fluid of the heat exchanger is increased

the heat transfer coefficient of the heat exchanger first decreases and then increases

and there is an optimal value; Due to the high proportion of thermal resistance in the cold side

the similarities and differences of heat transfer characteristics of cold side supercritical carbon dioxide under buoyancy and thermal acceleration under different operating parameters are compared; It is found that in the quasi critical region

the strong buoyancy will greatly enhance the cold side heat transfer

while the acceleration effect will inhibit the heat transfer.