Computational fluid dynamics modeling of the flow in a laboratory membrane filtration cell operated at low recoveries

Abstract

Scaled-down models of industrial filtration units are often used in laboratory studies of membrane processes. Knowledge of the flow field and shear stresses at the membrane surface is vital for the accurate interpretation of bench scale experiments. In this paper, we present results of computational fluid dynamics modeling of the flow within the SEPA CF flat sheet membrane filtration cell operated at low recoveries. The problem was formulated as the steady-state isothermal laminar flow of incompressible Newtonian fluid. Pressure, velocity, and shear stress distributions were computed with 1 mm resolution for different average inlet velocities. Flow was found to be unidirectional over most of the channel area with exception of the corners of the channel. Stagnation areas in dead ends of inlet and outlet tubes and in the channel areas behind duct entries as well as local regions of high shear in duct-channel transition areas were observed. The relation between the highest shear rate created in this geometry and the average inlet velocity is given.