CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   CFX (http://www.cfd-online.com/Forums/cfx/)
-   -   Residuals converged but high (http://www.cfd-online.com/Forums/cfx/26449-residuals-converged-but-high.html)

Gilles September 30, 2008 15:17

Residuals converged but high
 
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

CycLone September 30, 2008 15:19

Re: Residuals converged but high
 
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

Glenn Horrocks September 30, 2008 20:05

Re: Residuals converged but high
 
Try this page:

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

Glenn Horrocks


All times are GMT -4. The time now is 00:04.