Heat transfer characteristics of mixed hydrocarbon refrigerant flow condensation in shell side of helically baffled shell-and-tube heat exchanger

For optimizing the helically baffled shell-and-tube heat exchanger (HBHX) used in the liquefied natural gas (LNG) process, the condensation heat transfer mechanism of the mixed hydrocarbon refrigerant flow condensation in shell side of HBHX should be known. In the present study, the ethane/propane mixture and the ethane/propane/butane mixture were used as the tested fluids for analyzing the heat transfer mechanism of mixed hydrocarbon refrigerants. The results show that, as the vapor quality increases, the heat transfer coefficient initially increases and then decreases, representing a maximum at vapor quality of 0.8 - 0.9; the two-phase condensation heat transfer coefficients of ethane/propane mixture and ethane/propane/butane mixture are smaller than that of pure propane by 29-72% and 71-44%, respectively. A heat transfer coefficient correlation for the mixed hydrocarbon refrigerant flow condensation in shell side of HBHX was developed within a deviation of ±25%.