[FerdiFuchs]

Good evening everyone!

im doing a lot of 2-phase flow calculations in pipes, especially annular-pipes at the moment with differing filling-levels.
my standard procedure is to split the inlet into two patches: inlet_liquid and inlet_vapor. Both of these Inlet patches are set up with an own alpha value and with the BC flowRateInletVelocity -- massFlowRate:



Actually gmsh is refining very much in lower angles at my inlet-patches (which leads to mesh distortions at the inlet patch).

Because of that, im trying to set up a case with only one inlet, which gets divided by groovyBC depending on the filling level of the pipe:

inlet
{
type groovyBC;
valueExpression "0";
fractionExpression "(pos().z > -0.002) ? 1 : 0";
value uniform 0;
}

This works very fine for alpha (as you can see in the attached screenshot -- inlet-patch).



my problem is the following: im working with high varrying massflowrates (velocities) for both phases. normally im using flowRateInletVelocity -- massFlowRate for both patches/phases, but this is not longer possible because of the usage of groovyBC and one inlet patch.
The distribution on one patch via groovyBC results in a not exact distributed area for the inlets and i need to adjust the velocity to get the requested massflowrates.

does anybody know how to realize this with groovyBC? how can i get the area values of the distributed inlet patch to recalculate the velocities to get the requested massflowrates?

any help is apreciated!
thanks a lot!
FerdiFuchs

Btw: this screenshot is just an example which should clarify my problem. the real inletpatch looks different

[FerdiFuchs]

solved it by using topoSet and createPatch instead of groovyBC.
Like my old method, with 2 patches and massflowrate-inlet.