[KeiJun]

Dear Sir,

I have used snappyHexMesh for the first time, and "checkMesh" is OK.

But, when I calculate simpleFoam solver using the generated mesh, velocity U rapidly decreases close on inlet (lower side of geometry), where there is no resistance such as porous. (see the attached picture1).

When I did "checkMesh -allTopology -allGeometry", I found concave cells error. (see the attached picture2 & 3, in which red color represents the concave cells.)

Do concave cells cause this U decrease?
On the other hand, I found some articles which say "don't have to worry about concave cells".
(for example, https://www.researchgate.net/post/Op...ve_Mesh_Error2)


My question is that, don't we really have to worry about concave cells?

If we should worry about this, how can we deal with?
If don't have to, do you think why U rapidly decreases?


I am looking forward to your advice and comment.

Sincerely,

KeiJun

[akidess]

http://www.cfd-online.com/Forums/ope...tml#post537935

http://www.cfd-online.com/Forums/ope...tml#post191366

[KeiJun]

Thank you for your reply.
They are very helpful information.

But then, do you think why does U decrease close to the inlet?


KeiJun