CFD Online Discussion Forums - 3 Questions about B.C

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3 Questions about B.C

Hi all,
Three questions about B.C:

1-What does it mean? (in bouyantPimpleFoam):

Code:

    outlet          

    ground

    {

        type            buoyantPressure;

        rho             rhok;

        value           uniform 0;

    }

2- what does it mean? (in pisoFoam):

Code:

    outlet          

    {

        type            inletOutlet;

        inletValue      uniform (0 0 0);

        value           uniform (0 0 0);

    }

3- As you know we need to define only one of P and U in boundaries but we must define something in OF for all parameters. so if we define pressure for example as fixed value what should be defined for U?

Thanks in advances,

Hi maysmech,
according to the userguide is the BC "inletoutlet" and I quote >>
Switches U and p between fixedValue and zeroGradient depending on direction of U inletValue, value. << I hope this helps you somehow :)
For the "buoyant" BC i really don't know how it works..
Greats

Thanks for your reply,
i don't know which B.C type should be used for U, when we set pressure as fixedValue and U is not fully developed to use zeroGradient.
Best,