[Fewi]

Hi All,


I am a beginner currently trying my best on simulating cavitation at a butterflyvavle in a pipe (DN700) with the interPhaseChangeFoam solver.
There is a ~0.43 m/s water flow coming in at high pressure (~12 bar). At the outlet, there is only atmospheric pressure. When the butterflyvalve is fully opened, the inlet speed exceeds 0.43 m/s. Whereas when the butterflyvalve is half open, the outlet lets out too much water, so that there is almost only air behind the butterfly valve. Could you please give me recommendations on which boundary conditions I should choose? Any help would be greatly appreciated.

for U I chose:

boundaryField
{
internalField uniform (0.433 0 0);


inlet
{
type zeroGradient;
value uniform (0.433 0 0);
}

outlet
{
type pressureInletOutletVelocity;
phi phi;
value $internalField;
}

for p I defined:

internalField uniform 1173565;

boundaryField
{
inlet
{
type totalPressure;
U U;
rho rho;
psi none;
gamma 1;
p0 uniform 1173565;
}

outlet
{
type totalPressure;
U U;
rho rho;
psi none;
gamma 1;
p0 uniform 101300;
}