[toughthinktank]

I am facing a problem in applying porous boundary conditions in a Diesel Particulate Filter. Geometry is such that there are two adjacent channels with porous separation in between, with only one end open on one side, while the other is plugged. So, one channel is used a s inlet for air and soot mixture, which comes out from the opposite. Since, the mixture passes through the porous wall, so soot gets trapped here forming a monolayer and then subsequent layers, continuously reducing the porosity, with each iteration.
I am using Euler-Langrangian scheme for calculation where particles are being tracked, so how do I apply porous boundary condition on substrate wall in fluent?
Moreover, how do I vary the porosity with each iteration based on the mathematical setup in the paper below?
http://www.sciencedirect.com/science...09250909004473