[Mark JIN]

Hi Friends,

I'm having an issue of mesh quality. If you look at the two figures I attached, the meshes at the transition areas between buildings and open spaces are quite coarse. Actually when I view the velocity result, the meshes look even worse and not fluent at all.

Can anyone help tell the reason and advice? I used snappyHex mesh to generate meshes.

Thanks in advance.

Mark

[Mark JIN]

Can anyone give any advice?

[Antimony]

Hi,

You have a pretty big change in your mesh size over a small area. Try to make the change in size more gradual.

Cheers,
Antimony

[Mark JIN]

Originally Posted by Antimony

Hi,

You have a pretty big change in your mesh size over a small area. Try to make the change in size more gradual.

Cheers,
Antimony

Hi Antimony,

Thanks for your reply.
I tried to increase 'ncellsbetweenlayers' from 5 to 15. Mesh quality looks better now. But still I can see two different colors （U magnitude) at the transient potion of two adjacent layers. Seems like somewhere wrong with my ground boundary condition.

Regards,
Mark

[Mark JIN]

Originally Posted by Antimony

Hi,

You have a pretty big change in your mesh size over a small area. Try to make the change in size more gradual.

Cheers,
Antimony

Hi Antimony,

Actually, that 'color contrast' phenomenon at transient portion only happens on the surface within one cell distance from coordinate Z=0.