Liquid suction heat exchangers are commonly installed in refrigeration system with the intent of ensuring proper system operation and increasing system performance. Previous researchers have investigated performance of liquid suction heat exchangers

and some of them have concluded that the relative capacity change index (RCI) will increase with the increasing of heat recovery efficiency for certain refrigerants. In this study

two kinds of liquid suction exchangers set up with different baffles are numerical simulated by ANSYS FLUENT using the refrigerant R404A. They are used in an automotive air conditioning system and almost have the same geometrical parameters. The results indicated that for the same mass flow rate the overall heat transfer rate and average heat transfer coefficient of the shell-and-tube heat exchanger with continuous helical baffles (CH-STHX) are higher than that of the shell-and-tube heat exchanger (STHX) by 32.2% and 41.7%. The shell-side average heat transfer coefficient of the liquid refrigerant in the CH-STHX is about 3.5 times higher than that of the STHX. As the price of heat transfer enhancement

the shell-side pressure drop of the CH-STHX is extremely increasing to 11 times larger than that of the STHX. While the tube-side heat transfer coefficient and pressure drop of the CH-STHX almost keep the same with that of the STHX. And most importantly

the heat recovery efficiency increases from 0.21 to 0.29 for the CH-STHX

by 38.1%.