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Old   September 30, 2008, 14:17
Default Residuals converged but high
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Gilles
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Hello CFD users ! I'm running a simulation over a 3D-Wing at 50m/s in a free stream. I use the SST-transition model. My solution converges but the RMS residuals are too high (about 1e-4), furthermore, I checked the lift and drag on the wing and it converges as well. Do I have the right solution ?

Thanks for your help

Gilles
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Old   September 30, 2008, 14:19
Default Re: Residuals converged but high
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CycLone
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If the residuals are high it is not converged. Converged means the residuals are sufficiently low, not that they have stopped going down.

Check the solution for regions of instability. Increasing your timestep may help (try a factor of 10). Also, check the mesh for regions of low quality and fix them if necessary.

-CycLone
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Old   September 30, 2008, 19:05
Default Re: Residuals converged but high
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Glenn Horrocks
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Try this page:

http://www.cfd-online.com/Wiki/Ansys...gence_criteria

Glenn Horrocks
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