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Issues whith kEpsilon and porous zones.

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Old   April 28, 2014, 14:29
Default Issues whith kEpsilon and porous zones.
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Fran
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Hi all,

I am trying to simulate an air duct with porousSimpleFoam, and in the first steps of the simulation epsilon around the porousZones rises to extremely high values (i.e.: 1E+09).

In some cases the epsilon bounding does its work and the case finally converges, but most times the solution cannot be reached.

This effect has happened repeatedly in different simulations, for different geometries, and I guess it is not a BC issue because the exact thing happens in pressure and velocity driven cases with completely different BCs.

Reynolds for these cases is around 450000. Ducts are rectangular and the mesh is unstructured (tet volumes) but made in a way that faces of the porous zone are completely planar.

OpenFoam version is 2.1.x.

Any comment on this issue will be welcome.
Best Regards.
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Old   April 28, 2014, 16:47
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Niels Gjoel Jacobsen
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Good evening,

Please be aware that the presence of the porous medium introduce additional terms in the turbulence equation, e.g. k and epsilon. You should verify that these are actually present in the turbulence closure of your choice.

Kind regards,

Niels
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