SimScale CAE Forum

Undeveloped flow problem in domain

Hi
I am using the mesh as a computational domain and sometimes the flow is not developed although I assign the boundary conditions properly. I could not find what the reason is.

Could you help me please?

The project link

Hey there,

I believe the meshes that were used for the simulations have been deleted? I can’t really tell what assignments were used for the simulation, since the mesh is no longer available.

It would be appreciated if you could reconstruct the mesh, so we have more insight on the boundary conditions.

On a side note, are you intending to define an ABL profile? Looking at the image that you posted, it looks like the top face of the enclosure, as well as the sides, received a no-slip wall condition, which is probably not intended.

The usual approach would be a “Slip” wall boundary condition, which allows velocities in the tangent direction.

Cheers

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Thank you for your support.
I am reconstructing the mesh again.
This is a validation case of AIJ. I am using the same boundary conditions with wind tunnel. Is “Slip” wall boundary condition suitable for wind tunnel? It has smooth wall surface.

Thanks for the additional insights.

If you are trying to mimic the effects of an actual wind tunnel, then setting the outer walls to “no-slip” would be the optimal approach.

When trying to mimic the effects of an “open environment wind tunnel”, then a slip wall would be more appropriate.

Cheers

Thank you for the information about the wind tunnel. By the way I found the reason of the problem.

Cheers

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Well, this reason is not present in your post marked as ‘Solution’. Would you be kind enough to elaborate, please?

Take care,

Retsam

Hi

In post-processing the time step should be more than zero as showed in the right picture.

Cheers