Hi, someone as an idea about the best boundary condition to simulate the wind flow in a generic area?

It's important to consider variable such flow rate, Mach number, ecc...

Adriano

What do you mean exactely? According to me, as the Mach number is defined, this kind of flowing can be considered uncompressible (M<1): do you agree? To relaize this simulation generally I consider a domain with a parallelepiped shape, in which the bottom face is the orography, defined like a no slip face, using k=0.7 and c=0.5; if the wind comes, for example from North, a face is considered like a velocity inlet and the opposite face like a pressure outlet; the two lateral face and the top face like a no shear stress wall. Generally I decrease the underelation coefficient and I use the K-epsilon turbulence model and I always try to obtain, with the region adaptation, 1.000.000 cells. Please let me know what dou you think about. Thanks advanced.

I think that a gas is incopressible at M<0.1, however in the case of open geometry, u can use far-boundary condition... try to see fluent manual for details, i think this is better in your case.

Adriano