Experimental and numerical investigations on enhanced and stabilized flow boiling of hydrocarbon fuel in micro-finned channel

Abstract

Due to the high heat transfer coefficient, flow boiling has applied in various industrial fields. Previous literature mainly focuses on the enhancement methods of flow boiling for water or refrigerants, with few reports on the enhancement of flow boiling for hydrocarbon fuels. Therefore, in this study, we design different types of micro-finned surface with strong capillary force to increases the nucleate sites and keep the wall in a superwetting state during the flow boiling to postpone the appearance of “annular bubble” flow. The influence of fin width, fin height, fin spacing and coolant type on boiling heat transfer through experiments and numerical simulation. The results show that the wider the fin width, the lower the fin height, the smaller the fin spacing, the stronger the heat transfer enhancement effect, and the more stable the flow boiling. The best heat transfer performance of the finned surface is achieved with the average wall temperature 27 °C lower and heat transfer coefficient 1.9 times higher than the smooth surface. Moreover, the heat transfer coefficient of hydrocarbon fuel is 43.3% larger than that of deionized water.