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- - Probes (https://www.cfd-online.com/Forums/openfoam-pre-processing/62201-probes.html)

I have successfully been able

I have successfully been able to run a 2D case for flow past an obstacled in a channel. I now wish to extract the frequency of vortex shedding for which I wish to create a monitor point for Y-velocity (my flow is in the X-direction) on the channel centerline. Can someone help me with the procedure for doing this?

I would appreciate if you could also include the steps for any code compilation (if necessary).

Thanks very much for taking time to read my post.

See the 'probes' functionality

See the 'probes' functionality in e.g. the oodles solver (createProbes.H). Compile with 'wmake'.

Thanks for the response. In th

Thanks for the response. In the ~/OpenFOAM/OpenFOAM-1.3/applications/solvers/DNSandLES/oodles directory, I find the following files with the following contents:

***************
createProbes.H
***************

Info<< "Reading probeLocations\n" << endl;

IOdictionary probeLocations
(
IOobject
(
"probeLocations",
runTime.constant(),
mesh,
IOobject::MUST_READ,
IOobject::NO_WRITE
)
);

Info<< "Constructing probes\n" << endl;

Probe<volvectorfield> UProbe(probeLocations, U);
Probe<volscalarfield> pProbe(probeLocations, p);

**************
writeProbes.H
**************

UProbe.write();
pProbe.write();

*********
oodles.C
*********
#include "fvCFD.H"
#include "incompressible/singlePhaseTransportModel/singlePhaseTransportModel.H"
#include "incompressible/transportModel/transportModel.H"
#include "incompressible/LESmodel/LESmodel.H"
#include "IFstream.H"
#include "OFstream.H"
#include "Random.H"
#include "Probe.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

int main(int argc, char *argv[])
{

# include "setRootCase.H"
# include "createTime.H"
# include "createMeshNoClear.H"
# include "readTransportProperties.H"
# include "createFields.H"
# include "createAverages.H"
# include "createProbes.H"
# include "initContinuityErrs.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

Info<< "\nStarting time loop\n" << endl;

for (runTime++; !runTime.end(); runTime++)
{
Info<< "Time = " << runTime.timeName() << nl << endl;

# include "readPISOControls.H"
# include "CourantNo.H"

sgsModel->correct();

fvVectorMatrix UEqn
(
fvm::ddt(U)
+ fvm::div(phi, U)
+ sgsModel->divB(U)
);

if (momentumPredictor)
{
solve(UEqn == -fvc::grad(p));
}

// --- PISO loop

(p4 of 5)
for (int corr=0; corr<nCorr; corr++)
{
volScalarField rUA = 1.0/UEqn.A();

U = rUA*UEqn.H();
phi = (fvc::interpolate(U) & mesh.Sf())
+ fvc::ddtPhiCorr(rUA, U, phi);

adjustPhi(phi, U, p);

for (int nonOrth=0; nonOrth<=nNonOrthCorr; nonOrth++)
{
fvScalarMatrix pEqn
(
fvm::laplacian(rUA, p) == fvc::div(phi)
);

pEqn.setReference(pRefCell, pRefValue);
pEqn.solve();

if (nonOrth == nNonOrthCorr)
{
phi -= pEqn.flux();
}
}

# include "continuityErrs.H"

(p5 of 5)
U -= rUA*fvc::grad(p);
U.correctBoundaryConditions();
}

# include "calculateAverages.H"

runTime.write();

# include "writeNaveragingSteps.H"

# include "writeProbes.H"

Info<< "ExecutionTime = " << runTime.elapsedCpuTime() << " s"
<< " ClockTime = " << runTime.elapsedClockTime() << " s"
<< nl << endl;
}

Info<< "End\n" << endl;

return(0);
}

// ************************************************** *********************** //

I would really appreciate if someone could quickly point out what needs to be changed and where. Also, I'm terrible in C++, so a more detailed explanation is always welcome!

And sorry for pasting all this code. I know this isn't right, but I really need to get this probe working. Any help is gratefully appreciated!

Thanks for the response. In th

Darn! What a mess. My apologie

Darn! What a mess. My apologies for the dual post. If only the server responded faster http://www.cfd-online.com/OpenFOAM_D...lipart/sad.gif