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Scalar transport

The scalarTransport function object evolves a scalar transport equation, which can be seeded using

  • boundary conditions, e.g. fixed value
  • equation sources, e.g. fvOptions

Usage​

Basic operation of the scalarTransport function object comprises:

scalar1
{
    type            scalarTransport;
    libs            ("libsolverFunctionObjects.so");
}

For more complete control, the full set of input entries includes:

scalar1
{
    type            scalarTransport;
    libs            ("libsolverFunctionObjects.so");


    // Optional entries

    // Name of scalar field to transport, default = 's'
    field           vapour;

    // Name of flux field, default = 'phi'
    phi             phi;

    // Name of density field for compressible cases, default = 'rho'
    rho             rho;

    // Name of phase field to constrain scalar to, default = 'none'
    phase           none;

    // Set the scalar to zero on start/re-start
    resetOnStartUp  no;

    // Name of field to use when looking up schemes from fvSchemes
    // default = <field>
    schemesField    U;


    // Diffusivity

    // Fixed value diffusivity
    D               0.001;

    // Name of field to use as diffusivity, default = 'none'
    nut             none;

    // Run-time selectable sources
    fvOptions
    {
        ...
    }
}

Order of importance when setting the diffusivity

  • Fixed value: D
  • Field value: nut
  • If none, the code will
    • attempt to retrieve the effective viscosity from a turbulence model, or
    • set a value of zero

Sample output​

The scalar will only be bounded if evolved using the upwind scheme.

Further information​

Source code:

API:

Example usage: