User-defined Convergence Criteria

PorscheGTIII · April 17, 2013, 18:41

Hello All!

I know that Fluent judges convergence of your solution by reaching a prescribed residual value. I also know that you should monitor properties such as lift, drag and moment coefficents to judge converge.

My question is, is there a way to add these monitor properties to the automatic convergence check that Fluent makes to the Residuals? Say you want the solution to be considered converged if the change in moment coefficient between timesteps in a transient run is less than a certain value and you want Fluent to recognize this and complete the simulation.

Is the capability apart of Fluent or can a UDF be written to do this? Is there already a UDF available for this?

Thanks!

vasava · April 18, 2013, 02:53

I am not sure about the UDF but you can write a scheme file to do so.

PorscheGTIII · April 18, 2013, 13:29

Quote:

Originally Posted by vasava

I am not sure about the UDF but you can write a scheme file to do so.

Nice! Do you know of any scheme files that can do this or something similar that would be a good place to start?

vasava · April 19, 2013, 01:15

I have not done any Scheme programming my self but may be this webpage might be of some help to you. http://www.eureka.im/745.html

April 17, 2013, 18:41	User-defined Convergence Criteria	#1
PorscheGTIII New Member Chris Join Date: Jan 2012 Posts: 17 Rep Power: 14	Hello All! I know that Fluent judges convergence of your solution by reaching a prescribed residual value. I also know that you should monitor properties such as lift, drag and moment coefficents to judge converge. My question is, is there a way to add these monitor properties to the automatic convergence check that Fluent makes to the Residuals? Say you want the solution to be considered converged if the change in moment coefficient between timesteps in a transient run is less than a certain value and you want Fluent to recognize this and complete the simulation. Is the capability apart of Fluent or can a UDF be written to do this? Is there already a UDF available for this? Thanks!

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April 18, 2013, 02:53		#2
vasava Senior Member Paritosh Vasava Join Date: Oct 2012 Location: Lappeenranta, Finland Posts: 732 Rep Power: 22	I am not sure about the UDF but you can write a scheme file to do so.

April 19, 2013, 01:15		#4
vasava Senior Member Paritosh Vasava Join Date: Oct 2012 Location: Lappeenranta, Finland Posts: 732 Rep Power: 22	I have not done any Scheme programming my self but may be this webpage might be of some help to you. http://www.eureka.im/745.html