[Jonny6001]

Hi, I am running some simulations of tapering and straight pipes, trying to optimise for max volumetric flow.

At the moment the geometry is drawn in CATIA then imported in to Gambit as an IGES. I then sew the faces in to a volume and simply generate a volume mesh Tet/Hybrid with spacing 1, the pipe is 70mm long with diameter 40mm. This gives me slightly over 400,000 elements which I think is a little too much. I have ran all my simulations with each pipe having around this many elements and the results are pretty good.

What I would like to know is, how would I go about getting an even finer mesh in the boundary layer region and grown the element size further from the walls? I have done this in the past with 2D geo but I don't know how it works for 3D. Is there a simple 3D pave method or do I have to split the geometry up in to zones and mesh them individualy?

Thanks a lot