Hello,
What is the difference between pressure inlet velocity and pressure inlet-outlet velocity in the custom boundary condition in CFD? When would you use each?
Thanks
Hi @dunnoebruh. I know what such B.C’s do in OpenFOAM, but I am not 100% sure for SimScale. So I will leave some question marks if I am not sure:
Pressure inlet-outlet velocity:
- If the flow leaves the domain, treats it as a zero-gradient.
- If backflow is present (flow into the domain), sets a predefined velocity. I see no such option in SimScale, so I suppose it is set to 0 to avoid backflow, right???
- Applicable to vector fields (i:e: Velocity field):
- Useful as an outlet for highly unstable flows where backflow is possible.
Pressure inlet - velocity:Pressure Inlet and Outlet | Boundary Conditions | SimScale tells you what it does:
- It is an inlet B.C.
- It is used when you know the inlet pressure (but not the velocity) or when you are setting the velocity at the outlet. But how is the ref. pressure set???
- In theory you should be able of setting a reference pressure value but this is not the case.