convergence criterium without normalization

Raambi · July 2, 2011, 06:52

Hello,

im working on an free jet with STARCCM+ and try to get an converged solution.

In the Dokumentation of CD-Adapco they propose an criterium of 10^-3 for all Residuals.

For normalized Residuals i am nearly not able to keep this condition.

When i turning the normalizationoption off, it is no Problem to get Residuals under 10^-6.

What do u think is the better way to judge the Residuals. With normalization or without? And what do u think is the absolute value the residuals should fall under, when turning the normalization off?

Thanks for every help ;-) And if u dont understand because of my bad English skills ask and i will try to formulate the parts new.

Kind Regards

abdul099 · July 10, 2011, 06:38

I think, you should judge convergence by looking on some engineering values, not just residuals. For example, look on a mass flow through a boundary, lift or drag or whatever coefficients, or the values you are interested in.

July 2, 2011, 06:52	convergence criterium without normalization	#1
Raambi New Member Join Date: May 2011 Posts: 6 Rep Power: 15	Hello, im working on an free jet with STARCCM+ and try to get an converged solution. In the Dokumentation of CD-Adapco they propose an criterium of 10^-3 for all Residuals. For normalized Residuals i am nearly not able to keep this condition. When i turning the normalizationoption off, it is no Problem to get Residuals under 10^-6. What do u think is the better way to judge the Residuals. With normalization or without? And what do u think is the absolute value the residuals should fall under, when turning the normalization off? Thanks for every help ;-) And if u dont understand because of my bad English skills ask and i will try to formulate the parts new. Kind Regards

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July 10, 2011, 06:38		#2
abdul099 Senior Member Join Date: Oct 2009 Location: Germany Posts: 636 Rep Power: 22	I think, you should judge convergence by looking on some engineering values, not just residuals. For example, look on a mass flow through a boundary, lift or drag or whatever coefficients, or the values you are interested in.