CFD simulation of heat and mass transport for water transfer through hydrophilic membrane in direct-contact membrane distillation process

AbstractIn this study, direct-contact membrane distillation (DCMD) process is simulated using computational fluid dynamics. The DCMD process is typically used to provide pure water from salt water. The system consists of a flat-sheet membrane, a feed channel with salt water as the food, and a permeate channel. The cross-current flow pattern is used in this process. The governing equations to simulate the process include the heat, mass, and momentum balance equations. The developed equations are solved numerically using the finite element scheme. To improve accuracy of the simulation results and precision of water vapor diffusion coefficient estimation in membrane pores, a composition of Poiseuille and Knudsen diffusion coefficient is applied. The simulation results are compared with experimental data obtained from the literature and a satisfactory agreement is obtained (average error less than 5%).