[BarakeX]

Hello,

I am trying to simulate flow through an air filter with simpleFoam.
It has a filter body with an inlet and an outlet, and a simple cylinder (with a cut cylinder inside) as a filter element, which I defined as a porous media through fvOptions.

The geometry was all meshed with snappyHexMesh, even the cellZone for the porous element is defined there.

Whenever I un the simulation with the porous zone in contact with the walls of the filter body, the solver gives unrealistic results and the velocity + pressure spikes (extremely high values) in random areas around the contact between the wall patch and the porous cell zone.

When I modify the filter element (porous) to have no contact with the walls, the simulation runs and gives reasonable results, but then the air goes over and inside the cylindrical hole of the filter element, which is not supposed to happen irl.

I saw a tutorial case folder where they used porousSimpleFoam, but it was kind of complicated for me to look into since I'm short on time, I saw that they defined another boundary that they called "porousWalls" which was in contact with the walls of the simulation domain, I couldn't find out how he defined it and it worked.

I have attached a picture of the geometry.

Any idea how to get around this problem?