[aban]

i am working in openfoam, and my case is to simulate flow in a catalytic convertor. i have chosen my solver as porousSimpleFoam. but i found that this solver deals with steady condition. how can i change this to solve for unsteady condition or which file i must alter inorder to make it to solve unsteady conditions.
please help

[aban]

why no reply, where are the cfd experts

[romant]

I have never worked with the porous media solvers but here is what I would suggest:

Since there is no porousPimpleFoam you either have to modify the solver porousSimpleFoam yourself, meaning adding the parts that are missing for a transient simulation. Those are usually the time derivatives. Then recompile and run. If you want to follow this route, I would say compare simpleFoam and pimpleFoam and see what is different. porousSimpleFoam is a derivative of the simpleFoam solver.

The other option that I see is to use on of the other porous solvers, if applicable, http://www.openfoam.org/docs/user/standard-solvers.php . If they are not applicable, see if you can combine the knowledge that you can gain from these solvers (which are transient) and implement this into a porousPimpleFoam.

As said earlier, I have not used any of these solvers myself and can't say too much about applicability and/or ease of implementation of the transient part.