[sjlouie91]

Dear Foamers,

I have a quite weird problem when I run the incompressible LES for airfoil with roughness elements in Openfoam.

I monitored cl and cd, and the results went well before 10 flow-through time and it seems that it is almost converged and I planned to do time averaging. However, it started to diverge after 10 flow-through time. Is that the wrong boundary condition definitions? Attached are the nut and p contours and it seems that it started diverging from bottom boundary.

this is my boundary condition definition:
inlet: U(fixedValue), p(ZG), nut(calculated)
outlet: U(ZG), p(fixedValue 0), nut(ZG)
top&bottom: U(ZG), p(ZG), nut(ZG)

Are the boundary conditions defined correctly? Or is there any other problems which might caused divergence?

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Best regards,
Jin