http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4340.html

Now the specification of the LTS time scheme is simply:

ddtSchemes
{
    default         localEuler;
}

Replaces LTSReactingParcelFoam and LTSCoalChemistryFoam

    Select LTS via the ddtScheme:

        ddtSchemes
        {
            default         localEuler rDeltaT;
        }

Select LTS via the ddtScheme:

    ddtSchemes
    {
        default         localEuler rDeltaT;
    }

Select LTS via the ddtScheme:

    ddtSchemes
    {
        default         localEuler rDeltaT;
    }

    Select LTS via the ddtScheme:

        ddtSchemes
        {
            default         localEuler rDeltaT;
        }

Select using the optional

    consistent true;

setting in the PIMPLE dictionary of fvSolution.

This option is generally only beneficial for cases run in PIMPLE-mode
with a large maximum Courant number.

See tutorials/compressible/rhoSimpleFoam/squareBend

SIMPLE
{
    nNonOrthogonalCorrectors 0;
    rhoMin          0.1;
    rhoMax          1.0;
    transonic       yes;
    consistent      yes;

    residualControl
    {
        p               1e-3;
        U               1e-4;
        e               1e-3;

        // possibly check turbulence fields
        "(k|epsilon|omega)" 1e-3;
    }
}

relaxationFactors
{
    fields
    {
        p               1;
        rho             1;
    }
    equations
    {
        p               1;
        U               0.9;
        e               0.9;
        k               0.9;
        epsilon         0.9;
    }
}

e.g. in tutorials/compressible/rhoPimpleFoam/ras/angledDuctLTS

PIMPLE
{
    momentumPredictor   yes;
    transonic           no;
    nOuterCorrectors    50;
    nCorrectors         1;
    nNonOrthogonalCorrectors 0;
    consistent          yes;

    rhoMin          0.5;
    rhoMax          2.0;

    residualControl
    {
        "(U|k|epsilon)"
        {
            relTol          0;
            tolerance       0.0001;
        }
    }

    turbOnFinalIterOnly off;
}

relaxationFactors
{
    fields
    {
        "p.*"           0.9;
        "rho.*"         1;
    }
    equations
    {
        "U.*"           0.9;
        "h.*"           0.7;
        "(k|epsilon|omega).*" 0.8;
    }
}

Select LTS via the ddtScheme:

    ddtSchemes
    {
        default         localEuler rDeltaT;
    }

The LTS algorithm is currently controlled with the standard settings in
controlDict, e.g.:

    maxCo           0.5;
    maxDeltaT       2e-8;

with the addition of the optional rDeltaT smoothing coefficient:

    rDeltaTSmoothingCoeff 0.02;

which defaults to 0.02.

    ddtSchemes
    {
        default         localEuler rDeltaT;
    }

LTS is selected by the ddt scheme e.g. in the
tutorials/multiphase/interFoam/ras/DTCHull case:

ddtSchemes
{
    default         localEuler rDeltaT;
}

LTSInterFoam is no longer needed now that interFoam includes LTS
support.

to support any number of phases

correction in MovingPhaseModel<BasePhaseModel>::correct()

Patches provided by Timm Severin
Resolves bug-report http://www.openfoam.org/mantisbt/view.php?id=1764

to correspond to the phase dilatation rate.

to support any number of phases

to be phase-symmetric so that the results are independent of which
phase-fraction is solved.

    //- Return the set of times selected based on the argList options
    //  including support for \b -newTimes in which times are selected
    //  if the file <fName> does not exist in the time directory.
    //  Also set the runTime to the first instance or the
    //  \c constant/ directory if no instances are specified or available
    static instantList select
    (
        Time& runTime,
        const argList& args,
        const word& fName
    );

This is experimental functionality and currently on test in the yPlus
post-processing utility.

to support laminar simulations in the new framework.

Unfortunately this allows LES models to be instantiated although they
are not compatible with steady-state simulations.

Select LTS via the ddtScheme:

ddtSchemes
{
    default         localEuler rDeltaT;
}

The LTS algorithm is controlled with the standard settings in
controlDict, e.g.:

maxCo           0.5;
maxDeltaT       2e-8;

with the addition of the optional rDeltaT smoothing coefficient:

rDeltaTSmoothingCoeff 0.02;

which defaults to 0.02.

For cases with reasonably uniform meshes like the forwardStep tutorial
LTS does not provide much benefit but for cases with large variation in
cell-size like the biconic25-55Run35 tutorial LTS provides significant
speed-up to convergence particularly if started from uniform conditions.

Reverted changes proposed in
http://openfoam.org/mantisbt/view.php?id=1548 as it adversely affects
fixed-value BCs and is formulated to fix an issue with an unphysical
case.  Further analysis of the handling of fixed pressure outlet
conditions as the Mach number approaches 1 is required.