[Roxine]

Now there is a wall that is blocking the water flow, and I want to set the wall to be partially permeable, that is, to the porosity of the wall. I chose the wall as the same physical continuum as the fluid, and then set the wall area as the porous area. However, I found that the temperature of the water flow changed abnormally after running two steps. Could you tell me what went wrong?

Thank you!

[fluid23]

First, setting porosity will not allow fluid to pass through the wall. You will need to define resistance coefficients (inverse of permeability).

Second, in some cases, depending on your physics settings, materials and equation of state, a pressure change can cause a temperature change in the fluid. Since a porous region's primary purpose is to affect a pressure/momentum change, this could easily lead to a temperature change. The help material on porous regions has a whole section on this subject.

Since you haven't given any info about what your physical models/assumptions are, it's impossible to provide a solid answer. I suggest that you review all the help material on porous regions then decide how to proceed.

Edit: porosity plays a role in setting volume fractions for heat transfer and other calculations, but doesn't prescribe a pressure gradient that opposes the flow.

[Roxine]

Originally Posted by fluid23

First, setting porosity will not allow fluid to pass through the wall. You will need to define resistance coefficients (inverse of permeability).

Second, in some cases, depending on your physics settings, materials and equation of state, a pressure change can cause a temperature change in the fluid. Since a porous region's primary purpose is to affect a pressure/momentum change, this could easily lead to a temperature change. The help material on porous regions has a whole section on this subject.

Since you haven't given any info about what your physical models/assumptions are, it's impossible to provide a solid answer. I suggest that you review all the help material on porous regions then decide how to proceed.

Edit: porosity plays a role in setting volume fractions for heat transfer and other calculations, but doesn't prescribe a pressure gradient that opposes the flow.

Thank you for your answer. My model is a fluid with stratified water temperature, which improves the overflow water temperature through a wall. Now I am analyzing the influence of porosity on it. I think I should carefully consult the information about porous areas. Can I ask you for help if I encounter any problems?

Thank you very much!

[fluid23]

I think the help material is your best bet, but I will help if I can. My experience with the porous model is relegated to air filter media.