Discussion Forum

In the context of microfluidics, I am intending to model a membrane, with a certain degree of porosity, through which flow can pass from one channel to another. To fulfill this purpose, I believe I could employ two procedures. The first one would be using the Free and Porous Flow Module to model the mebrane by entering the respective porosity and permeability, whilst the rest of the channels would be defined by the Navier-Stokes equations. The second one though, would be to design every pore of the membrane individually, create a mesh for it, and then solve the model only using the Laminar Flow Module.

Both procedures lead to slightly different results, having that, I believe, using the Free and Porous Flow Module should provide the most accurate solution. However, my question is, what is the main difference between the two procedures mentioned? Wouldn't the Laminar Flow Module be enough to correctly characterize flow, providing that the membrane is designed pore-by-pore? Or is there something missing from this approach? What does Darcy's Law introduce of extra that the Navier-Stokes Equations, coupled with a membrane where every pore is modelled individually, doesn't?

I hope my questions are comprehensible. Thank you so much for the help!