Commit f330921c authored by Mark Olesen's avatar Mark Olesen Committed by Andrew Heather
Browse files

GIT: remove backup file

parent f37942b3
......@@ -2,7 +2,7 @@
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration |
\\ / A nd |
\\ / A nd | Copyright (C) 2019 OpenCFD Ltd.
\\/ M anipulation |
-------------------------------------------------------------------------------
| Copyright (C) 2011-2016 OpenFOAM Foundation
......
/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration |
\\ / A nd | Copyright (C) 2004-2011 OpenCFD Ltd.
\\/ M anipulation |
-------------------------------------------------------------------------------
| Copyright (C) 2011-2016 OpenFOAM Foundation
-------------------------------------------------------------------------------
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 <http://www.gnu.org/licenses/>.
Application
potentialFoam
Group
grpBasicSolvers
Description
Potential flow solver which solves for the velocity potential, to
calculate the flux-field, from which the velocity field is obtained by
reconstructing the flux.
\heading Solver details
The potential flow solution is typically employed to generate initial fields
for full Navier-Stokes codes. The flow is evolved using the equation:
\f[
\laplacian \Phi = \div(\vec{U})
\f]
Where:
\vartable
\Phi | Velocity potential [m2/s]
\vec{U} | Velocity [m/s]
\endvartable
The corresponding pressure field could be calculated from the divergence
of the Euler equation:
\f[
\laplacian p + \div(\div(\vec{U}\otimes\vec{U})) = 0
\f]
but this generates excessive pressure variation in regions of large
velocity gradient normal to the flow direction. A better option is to
calculate the pressure field corresponding to velocity variation along the
stream-lines:
\f[
\laplacian p + \div(\vec{F}\cdot\div(\vec{U}\otimes\vec{U})) = 0
\f]
where the flow direction tensor \f$\vec{F}\f$ is obtained from
\f[
\vec{F} = \hat{\vec{U}}\otimes\hat{\vec{U}}
\f]
\heading Required fields
\plaintable
U | Velocity [m/s]
\endplaintable
\heading Optional fields
\plaintable
p | Kinematic pressure [m2/s2]
Phi | Velocity potential [m2/s]
| Generated from p (if present) or U if not present
\endplaintable
\heading Options
\plaintable
-writep | write the Euler pressure
-writePhi | Write the final velocity potential
-initialiseUBCs | Update the velocity boundaries before solving for Phi
\endplaintable
\*---------------------------------------------------------------------------*/
#include "fvCFD.H"
#include "pisoControl.H"
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
int main(int argc, char *argv[])
{
argList::addNote
(
"Potential flow solver which solves for the velocity potential"
);
argList::addOption
(
"pName",
"pName",
"Name of the pressure field"
);
argList::addBoolOption
(
"initialiseUBCs",
"Initialise U boundary conditions"
);
argList::addBoolOption
(
"writePhi",
"Write the final velocity potential field"
);
argList::addBoolOption
(
"writep",
"Calculate and write the Euler pressure field"
);
argList::addBoolOption
(
"withFunctionObjects",
"Execute functionObjects"
);
#include "addCheckCaseOptions.H"
#include "setRootCaseLists.H"
#include "createTime.H"
#include "createMesh.H"
pisoControl potentialFlow(mesh, "potentialFlow");
#include "createFields.H"
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Info<< nl << "Calculating potential flow" << endl;
// Since solver contains no time loop it would never execute
// function objects so do it ourselves
runTime.functionObjects().start();
MRF.makeRelative(phi);
adjustPhi(phi, U, p);
// Non-orthogonal velocity potential corrector loop
while (potentialFlow.correctNonOrthogonal())
{
fvScalarMatrix PhiEqn
(
fvm::laplacian(dimensionedScalar("1", dimless, 1), Phi)
==
fvc::div(phi)
);
PhiEqn.setReference(PhiRefCell, PhiRefValue);
PhiEqn.solve();
if (potentialFlow.finalNonOrthogonalIter())
{
phi -= PhiEqn.flux();
}
}
MRF.makeAbsolute(phi);
Info<< "Continuity error = "
<< mag(fvc::div(phi))().weightedAverage(mesh.V()).value()
<< endl;
U = fvc::reconstruct(phi);
U.correctBoundaryConditions();
Info<< "Interpolated velocity error = "
<< (sqrt(sum(sqr(fvc::flux(U) - phi)))/sum(mesh.magSf())).value()
<< endl;
// Write U and phi
U.write();
phi.write();
// Optionally write Phi
if (args.found("writePhi"))
{
Phi.write();
}
// Calculate the pressure field from the Euler equation
if (args.found("writep"))
{
Info<< nl << "Calculating approximate pressure field" << endl;
label pRefCell = 0;
scalar pRefValue = 0.0;
setRefCell
(
p,
potentialFlow.dict(),
pRefCell,
pRefValue
);
// Calculate the flow-direction filter tensor
volScalarField magSqrU(magSqr(U));
volSymmTensorField F(sqr(U)/(magSqrU + SMALL*average(magSqrU)));
// Calculate the divergence of the flow-direction filtered div(U*U)
// Filtering with the flow-direction generates a more reasonable
// pressure distribution in regions of high velocity gradient in the
// direction of the flow
volScalarField divDivUU
(
fvc::div
(
F & fvc::div(phi, U),
"div(div(phi,U))"
)
);
// Solve a Poisson equation for the approximate pressure
while (potentialFlow.correctNonOrthogonal())
{
fvScalarMatrix pEqn
(
fvm::laplacian(p) + divDivUU
);
pEqn.setReference(pRefCell, pRefValue);
pEqn.solve();
}
p.write();
}
runTime.functionObjects().end();
runTime.printExecutionTime(Info);
Info<< "End\n" << endl;
return 0;
}
// ************************************************************************* //
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