Experimental study on refrigerant distribution and evaporation characteristics of different diameter micro channels in airfoil-shaped tube

Abstract

This study experimentally investigated the refrigerant distribution and evaporation characteristics in parallel micro channels in airfoil-shaped tube. Test section consisted of two stainless steel tubes that have inner diameter of 0.8mm using R134a as the refrigerant. The effects of heat flux and heat flux ratio on refrigerant distribution, pressure drop and evaporation heat transfer were investigated. The results revealed that mass flow rate ratio and pressure drop decreased with increasing heat flux ratio. Moreover, it was found that with increasing heat flux ratio, the variation of the vapor quality of the tube with high heat flux condition became larger due to the decrease of mass flux.