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Semi implicit source

Properties​

A typical transport equation takes the form:

DDtx=S(x) \frac{D}{Dt}x = S(x)

where the source, S(x)S(x), is decomposed into explicit and (linearised) implicit contributions

S(x)=Su⏟explicit+Spx⏟implicit S(x) = \underbrace{S_u}_{\mathrm{explicit}} + \underbrace{S_p x}_{\mathrm{implicit}}

Usage​

The source is available as a general option, specified using:

generalSource
{
    type            <type>SemiImplicitSource;

    ...

    volumeMode      absolute; // absolute | specific

    injectionRateSuSp
    {
        <field>           (<explicit value> <implicit coefficient>);
        ...
    }
}

Where <type> is a primitive field type, e.g. scalar, vector, tensor. As an example, a scalar source applied to the k and epsilon turbulence equations could take the form:

scalarSource
{
    type            scalarSemiImplicitSource;
    duration        1000.0;
    selectionMode   all;

    volumeMode      absolute;

    injectionRateSuSp
    {
        k           (30.7 0);
        epsilon     (1.5  0);
    }
}

Further information​

Tutorials

Source code