Numerical study on heat transfer enhancement by spray-sublimation cooling with dry ice particles

Abstract

In decades, the high-power electronic devices thermal management problem is becoming increasingly prominent, which restricts the development of electronic devices. A novel numerical method of spray-sublimation cooling with dry ice particles is presented in the paper. Based on the CFD two-phase solver, the key factors of heat transfer enhancement and heat transfer prediction are explored. The gas–solid two-phase spray cooling is analyzed and calculated with the sublimation mathematical model applied by UDF. The effects of dry ice sublimation spray cooling performance are studied by different nozzle inlet velocities, dry ice proportions and heat source surface temperature. The results show that heat source surface temperature, cooling heat flux and heat transfer coefficient are distributed in a ring under the same heating heat flux. The lower the heat source surface temperature near the nozzle, the higher the cooling heat flux and heat transfer coefficient. Cooling heat flux and heat transfer coefficient are improved with the increase of nozzle inlet velocity and dry ice proportion. The influence of inlet velocity and dry ice proportion on cooling performance is more intense than heat source surface temperature. When the nozzle inlet velocity is 30 m/s, dry ice proportion is 40% and heat source surface temperature is 55 °C, relatively optimal cooling heat flux is 300 W/cm2. The relatively optimal heat transfer coefficient reaches 40,000 W/(m2·°C) when heat source surface temperature is 20 °C.