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Description

The waveTransmissive is a general boundary condition that provides a wave transmissive outflow condition, based on solving DDt(W, field) = 0 at the boundary, W is the wave velocity and field is the field to which this boundary condition is applied.

The wave speed is calculated using:

\[w_p = \frac{\phi_p}{|\vec{S}_f|} + \sqrt{\frac{\gamma}{\psi_p}}\]

where:

Property Description
\(w_p\) Patch wave speed
\(\phi_p\) Patch face flux
\(\psi_p\) Patch compressibility
\(\vec{S}_f\) Patch face area vector
\(\gamma\) Ratio of specific heats

Usage

The condition requires entries in both the boundary and field files.

Boundary file 

<patchName>
{
    type            patch;
    ...
}

Field file 

<patchName>
{
    // Mandatory entries
    type            waveTransmissive;
    gamma           <scalar>;

    // Optional entries
    psi             <word>;

    // Inherited entries
    ...
}

where:

Property Description Type Required Default
type Type name: waveTransmissive word yes -
gamma Ratio of specific heats scalar yes -
psi Name of compressibility field word no thermo:psi

The inherited entries are elaborated in:

Further information

Tutorial:

Source code:

API:

History:

  • Introduced in version 1.5