Multiscale Simulation Method for Flow and Mass-Transfer Characteristics in a Reverse Osmosis Membrane Module

2015-11-18T00:00:00Z (GMT) by Toru Ishigami Hideto Matsuyama
This paper presents a numerical simulation method for calculating flow and mass-transfer characteristics in an entire membrane sheet module comprised of feed and permeate channels. The channels, including the spacers, were coarse-grained as the porous media for simulation of the entire membrane sheet. This is because the previous unit cell concept, which directly calculates the flow and solute concentration fields around the spacers, cannot be extended to the meter-sized computational domain owing to computational load limitations. We first carried out the unit cell simulation of the spacer-filled channel to obtain the flow and mass-transfer characteristics. The obtained flow and mass-transfer characteristics were then used for modeling porous media. The flow and solute mass fraction fields were then calculated for a membrane sheet, and the effect of the spacer arrangement on the membrane sheet performance was investigated. From the relationship between the pressure drop and water permeation rate, significantly different correlations were found for two parameters: the distance between the spacers and the angle between the spacers.