Time schemes define how a property is integrated as a function of time, i.e.

Depending on the choice of scheme, field values at previous time steps are required, represented in the following as \(\old{\phi}\) and \(\oldold{\phi}\) for the old and old-old time levels.

Usage🔗

Time scheme properties are input in the fvSchemes file under the ddtSchemes sub-dictionary using the syntax:

ddtSchemes
{
    default         none;
    ddt(Q)          <time scheme>;
}

Options🔗

Available time schemes include

• Backward time scheme
• Crank-Nicolson time scheme
• Euler implicit time scheme
• Local Euler implicit/explicit time scheme
• Steady state time scheme

Example🔗

See this example to see the relative performance of the schemes.

Further information🔗

Source code:

• $FOAM_SRC/finiteVolume/finiteVolume/ddtSchemes/ddtScheme

API:

• Foam::fv::ddtScheme