[MikeWorth]

I've got a model, which has a horizontal boundary where both fluids are present; the physics requires a constant pressure here, regardless of which fluid is touching the boundary. Setting a constant p_rgh boundary condition leads to an abrupt change in pressure at the liquid interface, breaking things.

Can anyone suggest a way to force a constant pressure here, not subtracting the hydrostatic bit?

Thanks,
Mike

[Wenyuan]

Please check out the prghPressure boundary condition for the p_rgh field.

[MikeWorth]

Thanks for pointing out what should have been obvious - I've got no idea how I missed that on the BC list, then failed to find anything with google?!?

[valdirene.rocho]

Good evening

Guys, I'm working with a two-phase flow (laminar) in openFoam 7 but I haven't managed to set the boundary conditions yet.
I'm using the interFoam solver.
My advisor suggested using the boundary condition below:

type pressureDirectedInletOutletVelocity;
phi phi;
rho rho;
inletDirection uniform (1 0 0);
value uniform 0;

However, the following error appears:

FOAM FATAL IO ERROR:
Expected a '(' while reading VectorSpace<Form, Cmpt, Ncmpts>, found on line 41043 the label 0

file: /home/valdirene/Documentos/Estado_transiente/pressureDirectedInletOutletVelocity/0/U.boundaryField.saidaInferior.value at line 41043.

From function Foam::Istream& Foam::Istream::readBegin(const char*)
in file db/IOstreams/IOstreams/Istream.C at line 92.

FOAM exiting

Segmentation fault (core dumped)

Can someone help me? Whether using this boundary condition or how to fix the problem.

[MikeWorth]

In the future you should post questions like these in a new thread to ensure that more people see it, rather than on the end of an existing one.

That said, it looks like you need to change:

value uniform 0;

to:

value uniform (0 0 0);

It's complaining about not finding a bracket where it expects one; it's expecting one because it needs a vector for the initial velocity. You've given it 0 on it's own, which is a scalar.