Avoids slight phase-fraction unboundedness at entertainment BCs and improved
robustness.

Additionally the phase-fractions in the multi-phase (rather than two-phase)
solvers are adjusted to avoid the slow growth of inconsistency ("drift") caused
by solving for all of the phase-fractions rather than deriving one from the
others.

e.g. in tutorials/heatTransfer/buoyantSimpleFoam/externalCoupledCavity/0/T

    hot
    {
        type            externalCoupledTemperature;
        commsDir        "${FOAM_CASE}/comms";
        file            "data";
        initByExternal  yes;
        log             true;
        value           uniform 307.75; // 34.6 degC
    }

Previously both 'file' and 'fileName' were used inconsistently in different
classes and given that there is no confusion or ambiguity introduced by using
the simpler 'file' rather than 'fileName' this change simplifies the use and
maintenance of OpenFOAM.

Resolves bug-report https://bugs.openfoam.org/view.php?id=2422

Patch contributed by Bruno Santos
Resolves patch request https://bugs.openfoam.org/view.php?id=2238

Patch contributed by Bruno Santos
Resolves patch request https://bugs.openfoam.org/view.php?id=2410

e.g. in the reactingFoam/laminar/counterFlowFlame2DLTS tutorial:

PIMPLE
{
    momentumPredictor no;
    nOuterCorrectors  1;
    nCorrectors     1;
    nNonOrthogonalCorrectors 0;

    maxDeltaT       1e-2;
    maxCo           1;
    alphaTemp       0.05;
    alphaY          0.05;
    Yref
    {
        O2          0.1;
        ".*"        1;
    }
    rDeltaTSmoothingCoeff 1;
    rDeltaTDampingCoeff 1;
}

will limit the LTS time-step according to the rate of consumption of 'O2'
normalized by the reference mass-fraction of 0.1 and all other species
normalized by the reference mass-fraction of 1.  Additionally the time-step
factor of 'alphaY' is applied to all species.  Only the species specified in the
'Yref' sub-dictionary are included in the LTS limiter and if 'alphaY' is omitted
or set to 1 the reaction rates are not included in the LTS limiter.

Resolves bug-report https://bugs.openfoam.org/view.php?id=2398

Combined 'dQ()' and 'Sh()' into 'Qdot()' which returns the heat-release rate in
the normal units [kg/m/s3] and used as the heat release rate source term in
the energy equations, to set the field 'Qdot' in several combustion solvers
and for the evaluation of the local time-step when running LTS.

Patch contributed by Juho Peltola, VTT.

Patch contributed by Juho Peltola, VTT

sprayFoam: Added support for the optional 'solveFlow' control to allow
           simulation of the spray evolution with all sub-models in a 'frozen'
           flow-field.

Resolves bug-report http://bugs.openfoam.org/view.php?id=2372

Resolves bug-report http://bugs.openfoam.org/view.php?id=2374

Resolves bug-report http://bugs.openfoam.org/view.php?id=2366

  - provides support for manipulating polyMesh/boundary

  - changed behaviour of disableFunctionEntries option to preserve
    #include

  - dictionary: added reading of lists of dictionaries.
    + each list element may be accessed using the 'entryDDD' keyword
      according to their list index.

Patch contributed by Mattijs Janssens

cellZones and pointZones can now be created in one action without the
need to first create a cellSet or pointSet and converting that to the
corresponding zone, e.g.

actions
(
    // Example: create cellZone from a box region
    {
        name    c0;
        type    cellZoneSet;
        action  new;
        source  boxToCell;
        sourceInfo
        {
            box   (0.04 0 0)(0.06 100 100);
        }
    }
);

'set -x' should be used for debugging.

Added command printing into wmake and Allwmake as a replacement for
'set -x' to log current target.

The 'Refresh' button updates the blockMesh and the GUI.

Added the interfacial pressure-work terms according to:

Ishii, M., Hibiki, T.,
Thermo-fluid dynamics of two-phase flow,
ISBN-10: 0-387-28321-8, 2006

While this is the most common approach to handling the interfacial
pressure-work it introduces numerical stability issues in regions of low
phase-fraction and rapid flow deformation.  To alleviate this problem an
optional limiter may be applied to the pressure-work term in either of
the energy forms.  This may specified in the
"thermophysicalProperties.<phase>" file, e.g.

pressureWorkAlphaLimit 1e-3;

which sets the pressure work term to 0 for phase-fractions below 1e-3.

For particularly unstable cases a limit of 1e-2 may be necessary.

This reverts commit 41643ef2.

See commit 527e1c87

Added 'READ_IF_PRESENT' option to support overriding of the default BCs
for complex problems requiring special treatment of Udm at boundaries.

Resolves bug-report http://bugs.openfoam.org/view.php?id=2317

Reconstructs the blockMesh and updates the display from the current
blockMeshDict so that any changes can viewed without exiting
paraFoam -block

Patch contributed by Mattijs Janssens

In many publications and Euler-Euler codes the pressure-work term in the
total enthalpy is stated and implemented as -alpha*dp/dt rather than the
conservative form derived from the total internal energy equation
-d(alpha*p)/dt.  In order for the enthalpy and internal energy equations
to be consistent this error/simplification propagates to the total
internal energy equation as a spurious additional term p*d(alpha)/dt
which is included in the OpenFOAM Euler-Euler solvers and causes
stability and conservation issues.

I have now re-derived the energy equations for multiphase flow from
first-principles and implemented in the reactingEulerFoam solvers the
correct conservative form of pressure-work in both the internal energy
and enthalpy equations.

Additionally an optional limiter may be applied to the pressure-work
term in either of the energy forms to avoid spurious fluctuations in the
phase temperature in regions where the phase-fraction -> 0.  This may
specified in the "thermophysicalProperties.<phase>" file, e.g.

pressureWorkAlphaLimit 1e-3;

which sets the pressure work term to 0 for phase-fractions below 1e-3.

to handle the change in density generated by the temperature correction.

Previously the inlet flow of phase 1 (the phase solved for) is corrected
to match the inlet specification for that phase.  However, if the second
phase is also constrained at inlets the inlet flux must also be
corrected to match the inlet specification.

Patch contributed by Mattijs Janssens
Resolves bug-report http://bugs.openfoam.org/view.php?id=2303

  - Write differences with respect to the specified dictionary
    (or sub entry if -entry specified)

  - Write the differences with respect to a template dictionary:
      foamDictionary 0/U -diff $FOAM_ETC/templates/closedVolume/0/U

  - Write the differences in boundaryField with respect to a
    template dictionary:
      foamDictionary 0/U -diff $FOAM_ETC/templates/closedVolume/0/U \
        -entry boundaryField

Patch contributed by Mattijs Janssens

For example, to mesh a sphere with a single block the geometry is defined in the
blockMeshDict as a searchableSurface:

    geometry
    {
        sphere
        {
            type searchableSphere;
            centre (0 0 0);
            radius 1;
        }
    }

The vertices, block topology and curved edges are defined in the usual
way, for example

    v 0.5773502;
    mv -0.5773502;

    a 0.7071067;
    ma -0.7071067;

    vertices
    (
        ($mv $mv $mv)
        ( $v $mv $mv)
        ( $v  $v $mv)
        ($mv  $v $mv)
        ($mv $mv  $v)
        ( $v $mv  $v)
        ( $v  $v  $v)
        ($mv  $v  $v)
    );

    blocks
    (
        hex (0 1 2 3 4 5 6 7) (10 10 10) simpleGrading (1 1 1)
    );

    edges
    (
        arc 0 1 (0 $ma $ma)
        arc 2 3 (0 $a $ma)
        arc 6 7 (0 $a $a)
        arc 4 5 (0 $ma $a)

        arc 0 3 ($ma 0 $ma)
        arc 1 2 ($a 0 $ma)
        arc 5 6 ($a 0 $a)
    ...