A lattice Boltzmann simulation of mass transport through composite membranes

Abstract

Composite membranes with a porous support layer and a dense skin layer have been extensively used in gas separation processes. A new approach, a mesoscale Lattice Boltzmann Simulation approach, is proposed and used to model the pore‐scale gas flow and mass transfer in the inhomogeneous membrane matrixes studied. Only physical forces are considered. Chemical forces are equivalently converted to physical forces through the relaxation time. Selective permeation of moisture through a composite membrane is modeled. The overall permeability is evaluated. It is found that mass transfer inhomogeneity exists not only in the porous media but also in the seemingly uniform dense skin layer. Increasing the diffusivity in the skin layer is more effective than decreasing the skin layer thickness in optimizing the overall membrane performance. The new approach gives more detailed insights into the directions for future design of composite membranes for gas separations like air dehumidification. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3925–3938, 2014

Moisture transport through asymmetric porous membranes with finger-like holes for indoor humidity control: A lattice Boltzmann simulation approach

“…The equilibrium distribution functions differentiated by the macroscopic variables, from equation (12), are represented by equations (44) to (46) …”

Lattice Boltzmann simulation of asymptotic longitudinal mass dispersion in reconstructed random porous media

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A priority supposition for estimation of time‐dependent changes in thickness and weight of polymeric flat sheet membranes fabricated by the nonsolvent induced phase separation (NIPS) technique

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