Hi, I want to visualise flow of water around an circular object. i'm solving a 2d problem here.i have 1 inlet and 1 outlet and the bottom is a wall.but,the top is a free surface. how do i set the top as a free surface? and what other boundary conditions can i apply for a incompressible flow? thanks.

For free surfaces you'll need to use the vof model. But before that try a run without the free surface and choose say a non-slip wall.

Greg

just set the flow speed and the pressure, this will work,,good luck.

How do i set non slip wall?coz in the wall boundary condition,i have options for wall roughness,moving wall and specified shear stress. Mavinakere.