/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration |
\\ / A nd | Copyright (C) 2011-2012 OpenFOAM Foundation
\\/ M anipulation |
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License
This file is part of OpenFOAM.
OpenFOAM is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with OpenFOAM. If not, see .
Class
Foam::activePressureForceBaffleVelocityFvPatchVectorField
Group
grpCoupledBoundaryConditions
Description
This boundary condition is applied to the flow velocity, to simulate the
opening or closure of a baffle due to local pressure or force changes,
by merging the behaviours of wall and cyclic conditions.
The baffle joins two mesh regions, where the open fraction determines
the interpolation weights applied to each cyclic- and neighbour-patch
contribution. This means that this is boundary condition is meant to be
used in an extra wall beyond an existing cyclic patch pair. See PDRMesh
for more details.
Once the threshold is crossed, this condition activated and continues to
open or close at a fixed rate using
\f[
x = x_{old} + s \times \frac{dt}{DT}
\f]
where
\vartable
x | baffle open fraction [0-1]
x_{old} | baffle open fraction on previous evaluation
s | sign for orientation: 1 to open or -1 to close
dt | simulation time step
DT | time taken to open the baffle
\endvartable
The open fraction is then applied to scale the patch areas.
\heading Patch usage
\table
Property | Description | Required | Default value
p | pressure field name | no | p
cyclicPatch | cyclic patch name | yes |
orientation | 1 to open or -1 to close | yes|
openFraction | current open fraction [0-1] | yes |
openingTime | time taken to open or close the baffle | yes |
maxOpenFractionDelta | max fraction change per timestep | yes |
minThresholdValue | minimum absolute pressure or force difference for activation | yes |
forceBased | force (true) or pressure-based (false) activation | yes |
\endtable
Example of the boundary condition specification:
\verbatim
myPatch
{
type activePressureForceBaffleVelocity;
p p;
cyclicPatch cyclic1;
orientation 1;
openFraction 0.2;
openingTime 5.0;
maxOpenFractionDelta 0.1;
minThresholdValue 0.01;
forceBased false;
}
\endverbatim
SourceFiles
activePressureForceBaffleVelocityFvPatchVectorField.C
\*---------------------------------------------------------------------------*/
#ifndef activePressureForceBaffleVelocityFvPatchVectorField_H
#define activePressureForceBaffleVelocityFvPatchVectorField_H
#include "fvPatchFields.H"
#include "fixedValueFvPatchFields.H"
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
namespace Foam
{
/*---------------------------------------------------------------------------*\
Class activePressureForceBaffleVelocityFvPatchVectorField Declaration
\*---------------------------------------------------------------------------*/
class activePressureForceBaffleVelocityFvPatchVectorField
:
public fixedValueFvPatchVectorField
{
// Private data
//- Name of the pressure field used to calculate the force
// on the active baffle
word pName_;
//- Name of the cyclic patch used when the active baffle is open
word cyclicPatchName_;
//- Index of the cyclic patch used when the active baffle is open
label cyclicPatchLabel_;
//- Orientation (1 or -1) of the active baffle patch.
// Used to change the direction of opening without the need for
// reordering the patch faces
label orientation_;
//- Initial wall patch areas
vectorField initWallSf_;
//- Initial cyclic patch areas
vectorField initCyclicSf_;
//- Initial neighbour-side cyclic patch areas
vectorField nbrCyclicSf_;
//- Current fraction of the active baffle which is open
scalar openFraction_;
//- Time taken for the active baffle to open
scalar openingTime_;
//- Maximum fractional change to the active baffle openness
// per time-step
scalar maxOpenFractionDelta_;
label curTimeIndex_;
//- Minimum value for the active baffle to start opening
scalar minThresholdValue_;
//- Force based active baffle
bool fBased_;
//- Baffle is activated
bool baffleActivated_;
public:
//- Runtime type information
TypeName("activePressureForceBaffleVelocity");
// Constructors
//- Construct from patch and internal field
activePressureForceBaffleVelocityFvPatchVectorField
(
const fvPatch&,
const DimensionedField&
);
//- Construct from patch, internal field and dictionary
activePressureForceBaffleVelocityFvPatchVectorField
(
const fvPatch&,
const DimensionedField&,
const dictionary&
);
//- Construct by mapping
activePressureForceBaffleVelocityFvPatchVectorField
(
const activePressureForceBaffleVelocityFvPatchVectorField&,
const fvPatch&,
const DimensionedField&,
const fvPatchFieldMapper&
);
//- Construct as copy
activePressureForceBaffleVelocityFvPatchVectorField
(
const activePressureForceBaffleVelocityFvPatchVectorField&
);
//- Construct and return a clone
virtual tmp clone() const
{
return tmp
(
new activePressureForceBaffleVelocityFvPatchVectorField(*this)
);
}
//- Construct as copy setting internal field reference
activePressureForceBaffleVelocityFvPatchVectorField
(
const activePressureForceBaffleVelocityFvPatchVectorField&,
const DimensionedField&
);
//- Construct and return a clone setting internal field reference
virtual tmp clone
(
const DimensionedField& iF
) const
{
return tmp
(
new activePressureForceBaffleVelocityFvPatchVectorField
(
*this,
iF
)
);
}
// Member functions
// Mapping functions
//- Map (and resize as needed) from self given a mapping object
virtual void autoMap
(
const fvPatchFieldMapper&
);
//- Reverse map the given fvPatchField onto this fvPatchField
virtual void rmap
(
const fvPatchVectorField&,
const labelList&
);
//- Update the coefficients associated with the patch field
virtual void updateCoeffs();
//- Write
virtual void write(Ostream&) const;
};
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
} // End namespace Foam
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
#endif
// ************************************************************************* //