Two boundary conditions in one patch
 

Hello!

Newbie here.
I'm trying to simulate turbulent flow in a open channel. At the bottom of the channel, I want to define the following boundary conditions dU/dz=0 and U=0. Is there any boundary that can do that? It seems that I need to combine a zerogradient (dU/dz)+ fixedvalue (u=0). Does anybody has some idea?

Thank you in advance.

That does not work. These conditions contradict each other.

Dear Uwe Pilz
Thank you for your reply.
I see. What about imposing one condition in one region and the other in the second region? I'm attaching a picture of what I would like to impose as boundary condition.
Thank you for your help in advance. https://www.dropbox.com/s/je63vstvwo...74932.jpg?dl=0

Hi, i do not know if this help but you can use swak4foam and teh use the groovyBCdirecton which is very powerfull. Maybe this fix your problem.

Br

Christian