Numerical Modeling of the Effects of Channel Configurations and Inclination Angles Inducing Buoyancy on Reverse Osmosis

This numerical study presents a comparison between two different reverse osmosis channel configurations. The physical properties were considered in the computational model as a function of the solute mass fraction. A critical comparison was performed between double-sided membrane channel and single-sided one considering the concentration and flow distribution. Gravitational effect was implemented by introducing the inclination of double membrane geometry for the first time in the literature of reverse osmosis systems. FORTRAN in-house code was developed to resolve conservation equations (mass, momentum, and solute mass fraction) based on the finite volume method. The results of the simulation show that the water recovery factor of double-membrane arrangement is two times higher than the single membrane arrangement. Concentration polarization (CP) can be reduced by both increasing the feed Reynolds number (Re) and decreasing the Aspect Ratio (AR). Considering the cases of low flow rates (up to Re = 40) with the flow orientation in the direction of gravity inducing buoyancy effects. The influence of the inclination showed that the average permeate flux, and the water recovery are proportional to the inclination angle up to the maximum values at the right angle (vertical plane).