How to control the growth rate of the unstructured mesh?
 

Dear all,

I wonder, how to control the growth rate of the unstructured domain.
As shown in the picture, for the structured domain, grid size near the wall is fine and the farfield is coarser. The size grows fast from the fine to the coarse, then stay the same size for the rest of the domain.
Is it possible the control the growth rate to make the grid size grow slowly from the fine to the coarse?
thanks in advance.
Attachment 31657

There's two ways you can control it. The first is with the boundary decay parameter (Select domain, Grid>Solve, Attributes panel, increase Boundary Decay above 0.5, Initialize). While it's not a "growth rate" per say, it does control the influence of the boundary spacing into the domain interior. This is the easiest and will probably get what you want.

The second, which will give you more control, is 2D T-Rex. This can also be found in Grid>Solve. Rather than me explain it, Pointwise has a nice do-it-yourself tutorial for it. I'll add one item not mentioned in it. Since you will likely extrude triangles from the edge shared by the adjacent extrusion, when you create the BC for those connectors choose the type Adjacent. This BC type will automatically determine the initial T-Rex height from the adjacent domain (note: this will only work for domains that were created through an extrusion).