CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   OpenFOAM (http://www.cfd-online.com/Forums/openfoam/)
-   -   Computing Streamwise Turbulent HeatFlux (http://www.cfd-online.com/Forums/openfoam/88874-computing-streamwise-turbulent-heatflux.html)

deji May 28, 2011 10:06

Computing Streamwise Turbulent HeatFlux
 
Hey there Foamers, I would like to confirm my understanding of calculating the streamwise turbulent heatflux, uT:

If I know Urms and Trms, can I take the product

uT= UrmsTrms ??

Thanks.

Thomas Baumann May 30, 2011 05:49

Hallo,

you can't do this:
you have to define the vectorfield
u*T, and get the mean-values out of this product and so get from this your rms values.

deji May 30, 2011 10:22

Thanks for the reply. I have checked, but it seems OpenFOAM fieldAverage does not have the capability of averaging u'T',v'T'. Is that so? Thanks much in advance.

Deji

Thomas Baumann June 1, 2011 05:29

Hi,

I would rewrite the solver and get an output similar to:

volVectorField UT
(
IOobject
(
"UT",
runTime.timeName(),
mesh,
IOobject::MUST_READ,
IOobject::AUTO_WRITE
),
U*T
);


and than in the controlDict:

functions
{
fieldAverage
{
type fieldAverage;
functionObjectLibs ("libfieldFunctionObjects.so");
enabled true;
outputControl outputTime;
fields
(
UT
{
mean on;
prime2Mean on;
base time;
}
);
}
}

Regards Thomas

deji June 1, 2011 11:32

Thank you very much Thomas. :)

Best regards,
Deji


All times are GMT -4. The time now is 06:12.