CFD Simulation Optimization Of Reverse Osmosis Membrane Module Screen

Reverse osmosis(RO)membranes have been widely used in wastewater treatment processes.in recent years,The use of computational fluid dynamics(CFD)to optimize the structure of reverse osmosis membrane modules has been the focus of research in recent years.The filament is an important part of the reverse osmosis membrane module,which not only plays a role of supporting the flow channel,but also can reduce the concentration polarization phenomenon and membrane pollution.Therefore,the optimization of the filament is the key to the optimization of the reverse osmosis membrane module.At present,the optimization of the filament mainly includes the thickness of the filament,the flow angle of attack,and the configuration of the filament.However,the current CFD simulation research of filament mainly uses a single,as many as 3-4 unit cells,which cannot comprehensively give the effect of changes in the parameters of the filament on the fluid in the membrane channel.Thence,this paper uses a model of multiple unit cells to systematically analyze the filament spacing,the flow angle of attack,and the filament thickness to provide theoretical support for the optimal design of the filament.Since the actual filament configuration is very complicated,a single unit cell is used in the simulation of the filament configuration.In the flow field simulation of reverse osmosis membrane module,the threedimensional models established in this subject have high resolution.The simulation of the filament spacing shows that the velocity field,pressure drop,and wall shear stress distribution in the membrane flow channel are at intermediate levels when the filament spacing is 4.And when the filament spacing is greater than 4,the average wall shear stress growth factor is almost unchanged.Taken together,when the filament spacing is equal to 4,this study considers it to be a more appropriate choice.The simulation of the flow angle of attack shows that the distribution at the angle of 45° makes the distribution of the narrow area uniform in the flow channel.Areas with increased local velocities appear alternately on the upper and lower walls,resulting in velocity and wall shear stress distributions superior to other flow angle of attack.At the same time,the growth factor of wall shear stress and pressure drop are also better than other angles.The research on the thickness of the filament shows that when the filament thickness is 30 mil,the velocity and the wall shear stress distribution in the membrane flow channel are the best,and the average wall shear stress growth factor is higher than other filament thickness.The research on the filament configuration shows that in the simulation design of the reverse osmosis membrane module,it is reasonable to use the cylindrical filament.Configuration 5 has a higher average wall shear stress,while the pressure drop does not increase significantly.