sHM - Creating boundary different boundary layers on different STL surface
 

Hello Everyone,

I am new to creating any mesh in OpenFOAM. I have a bit complex geometry (of a bus interior) and I want to create boundary layers on the inside surfaces of it.

As I know, I need to
1. create a bigger block mesh using blockMesh tool that encompasses the whole geometry, and
2. using a snappyHexMeshDict and STL surface of my geometry to create boundary layers.

However my problem is that it creates SAME boundary layer on all the geometry as I have only ONE STL file for my shape. my question is:

How can I assign different boundary layer thickness to different walls (patches) on my shape. Mind that in STL file, I cannot have patches defined (or can I?).

Please guide me. Thanks!

Amit