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Viewfactors - specified fixed radiation wall heat flux

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Old   June 12, 2014, 06:00
Default Viewfactors - specified fixed radiation wall heat flux
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Paweł Kuczyński
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Dear forumers,

is it possible to specify fixed total radiation wall heat flux using viewfactors radiation model in OpenFOAM?

I've looked into the boundary conditions for radiation in the path:

Code:
  /opt/openfoam211/src/thermophysicalModels/radiationModels/derivedFvPatchFields/
and the only available BC is greyDiffusiveRadiationViewFactor. And if we search for the implementation of this BC (ex. .../tutorials/heatTransfer/chtMultiRegionSimpleFoam/multiReagionHeaterRadioation/0/bottomAir/ ), for Qr we have:
Code:
boundaryField
{
  minX
  {
     type                   greyDiffusiveRadiationViewFactor;
     value                  uniform 0;
     emissivityMode    lookup;
     emissivity           uniform 1;
     Qro                    uniform 0;
  }
}
Does it mean that Qro is the specified total (net) radiative heat flux leaving the surface? Has anybody tried to use such a BC?

Any help is appreciated.
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Last edited by kuczmas; June 12, 2014 at 08:21.
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Old   June 12, 2014, 08:27
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Paweł Kuczyński
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Ok, I did my homework and cheked the meaning of Qro inside the class of greyDiffusiveViewFactorFixedValueFvPatchScalarFiel d.H.

So Qro is "external radiative heat flux". Therefore, I think it is not possible to specify total (net) radiative heat flux at wall. Correct me if I'm wrong...
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