Experimental investigation on pressure drop characteristics of two-phase hydrocarbon mixtures flow in the shell side of LNG spiral wound heat exchangers

The pressure drop characteristics of two-phase hydrocarbon mixtures flow in the shell side of spiral wound heat exchangers is a key factor in the application of such exchangers in liquefied natural gas (LNG) process. A cryogenic experimental rig was established to obtain pressure drop data and observe flow patterns in the present study. As main components of the working fluids at the shell side, ethane and propane mixtures were chosen as the tested fluid. The experimental conditions include ethane/propane molar ratios of 0:100, 10:90, 30:70, 60:40, mass fluxes of 40-80 kg (m2·s)−1 and vapor qualities of 0.2-0.9, respectively. The results show that, the frictional pressure drop increases with increasing mass flux and vapor quality; at the vapor qualities lower than 0.4, the frictional pressure drop decreases with increasing ethane molar ratio, while at the vapor qualities larger than 0.6, the frictional pressure drop increases with increasing ethane molar ratio. A correlation of pressure drop was developed covering 98% of the experimental data within a deviation of ±25%.