Computational fluid dynamic modeling of water desalination using low-energy continuous direct contact membrane distillation process

Highlights: • CFD modeling of water desalination using low-energy continuous DCMD process. • Full integrated and comprehensive modeling of mass, energy, and momentum transfer. • Impact of various operational parameters on DCMD system behavior. -- Abstract: In the present study, a comprehensive two-dimensional (2D) mathematical model was developed to investigate the behavior of the direct contact membrane distillation (DCMD) system using Computational Fluid Dynamics (CFD) technique. The model contains mass, energy, and momentum transfer phenomena equations, and can predict the amount of fresh water produced by the system. Governing equations of these transition phenomena were coupled in three domains, namely, membrane, hot and cold channels. The governing equations were discretized by using the finite volume method and then solved by MATLAB software. The developed model was validated with empirical data, and the results showed an excellent agreement between the empirical data and the model. Also, the impact of different parameters, including velocity, temperature, and length of channels was investigated on the system behavior. The results showed that the temperature and velocity of the input currents are very influential on the performance of this membrane distillation (MD) system. Both empirical and simulation results suggested that this type of water desalination system can be a very suitable and effective option for the challenges of human access to fresh water in the coming years.