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Hello,
For a 3D case (rectangular domain with 2 open boundaries and rest of the boundaries(top and bottom) closed), in the boundary condition file i used 2 2 2 (for depth, vel u, vel v) as boundary conditions and got the results that show the presence of velocity components along the solid lateral boundaries(NO SLIP BOUNDARY CONDITION is VIOLATED!).
a)I would like to have NO SLIP boundary condition along the SOLID LATERAL BOUNDARIES where the velocity components should be 0. How to set this condtion?

Sathya

Hello,

The no slip boundary condition is valid if you have a mesh size smaller than the viscous layer, which is very seldom the case, this is why we consider that the velocity on the solid boundaries is not 0, and that we are in the logarithmic profile, the boundary of the domain being slightly detached from the real boundary. This is what do most of the CFD software. If you really want to have 0 on the boundaries (not recommended) just set the values 2 0 0 instead of 2 2 2 in the boundary conditions file. Generally this tends to give too much friction on the walls.

With best regards,

Jean-Michel Hervouet