Hello @ddaum,
That is a valid question, especially that you need to use Custom BC to get access to these functionality.
The “standard” SimScale conditions are simplified for ease of use. At the same time you can get access to all BC types using Custom type, but with great power comes great responsibility! You simply need to specify all the BC types for all the fields required for the simulation, and the configuration needs to make sense.
Here is a picture of a BC setup for a no-slip rough wall.
This is a setup for Incompressible, turbulent (k-omega-SST), steady state simulation:
- velocity all to zero
- pressure gradient to zero
- turbulent kinetic energy (k) to Wall function and enable roughness
- turbulent dissipation (omega) to Wall function
Hope this helps!
Best
Pawel