Experimental study of heat transfer and pressure drop characteristics of two-phase mixed hydrocarbon refrigerants flow boiling in shell side of spiral wound heat exchanger

Abstract

The heat transfer and pressure drop characteristics of ethane/propane mixed hydrocarbon refrigerants flow boiling in shell side of spiral wound heat exchanger (SWHE) were investigated experimentally, and the ethane molar fractions of the mixed refrigerants cover 0%~60%. The results show that, as the vapor quality increases, the heat transfer coefficient (HTC) initially increases and then decreases sharply, representing a maximum value at vapor quality of 0.6~0.8; under mass flux of 40 kg m−2s−1 and heat flux of 6 kW m−2, as the ethane molar fraction increases from 0% to 60%, the HTC decreases maximally by 15% at vapor quality smaller than 0.7, while it increases maximally by 24% at vapor quality larger than 0.7. As the vapor quality is smaller than 0.4, the pressure drop of ethane and propane mixtures are lower maximumly by 17% than that of pure propane; as the vapor quality is larger than 0.6, the pressure drop of ethane and propane mixtures are higher maximumly by 41% than that of pure propane at the same working conditions.