Different grid spacing in Gambit - Fluent

Vasilis X

Hello.

I want to study the 2D-Backstep flow and for this reason I need to make a dense grid around the step region and a sparse grid in the rest of the area.

How can I do that? How can I define 2 or more different grid characteristics?

I have heard that internal, interior or interface boundary conditions might do the job but still I can't figure out how.

Any help - suggestion will be greatly appreciated.

Thanks in advance, Vasilis.