doubt criterion of convergence of the turbulence model

TallesC · July 21, 2014, 11:59

in my simulation consisting of an ode escoament one gas in a pipe, I specified crierio of convergence as a residue rms 1e-4 and 700 interactions. the simulation stopped at approximately 500 interactions, all variables reached the value of 1E-4 to the end, except the variable of turbulence, which may have occurred?

Obs. the model used was k-epson!!!

ghorrocks · July 21, 2014, 21:03

The only way to be sure is to run a sensitivity analysis. Do some simulations with tight and loose convergence tolerance on the turbulence equations and see if it makes a difference to the output variables of important to you.

TallesC · July 21, 2014, 22:06

how I can change only the criterion of convergence of the equations of turbulence in CFX-PRE?

ghorrocks · July 21, 2014, 22:21

Just use different global residuals convergence tolerance and note the residuals of the turbulence equations.

July 21, 2014, 11:59	doubt criterion of convergence of the turbulence model	#1
TallesC Senior Member Talles Caio Join Date: Oct 2012 Location: Brazil Posts: 101 Rep Power: 14	in my simulation consisting of an ode escoament one gas in a pipe, I specified crierio of convergence as a residue rms 1e-4 and 700 interactions. the simulation stopped at approximately 500 interactions, all variables reached the value of 1E-4 to the end, except the variable of turbulence, which may have occurred? Obs. the model used was k-epson!!!

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Fluent :- turbulence Model	prince_pahariaa	FLUENT	9	May 20, 2016 04:41
Compressible turbulence model issues	351Cleveland	OpenFOAM	5	October 24, 2013 16:41
question about turbulence model selection and sensitivity	karananand	Main CFD Forum	1	February 26, 2010 05:41
Centrifugal Pump and Turbulence Model	Michiel	CFX	12	January 25, 2010 04:20
turbulence model equation	Andy Chen	FLOW-3D	4	January 1, 2010 22:45

July 21, 2014, 21:03		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	The only way to be sure is to run a sensitivity analysis. Do some simulations with tight and loose convergence tolerance on the turbulence equations and see if it makes a difference to the output variables of important to you.

July 21, 2014, 22:06		#3
TallesC Senior Member Talles Caio Join Date: Oct 2012 Location: Brazil Posts: 101 Rep Power: 14	how I can change only the criterion of convergence of the equations of turbulence in CFX-PRE?

July 21, 2014, 22:21		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	Just use different global residuals convergence tolerance and note the residuals of the turbulence equations.