|November 7, 2012, 10:44||
Residual target for turbulence transport equations
Join Date: Oct 2010
Posts: 303Rep Power: 9
The CFX documentation states that the CFX solver internally uses a residual target of 10 times the specified value for the turbulence transport equations..
Could some one please explain the reason for this.
I know that residuals are not the only criteria to judge convergence and that one needs to look up for monitor points, flow imbalances and even see from the post processing if the obtained results make a complete physical sense.
Despite knowing all this I still have this question about the residuals.
My only interest is to know why such relatively large residual target is internally chosen for the turbulence transport equations by the CFX solver.
Could some one please provide an explanation.
|November 7, 2012, 17:40||
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 12,406Rep Power: 97
The turbulence equations do not directly affect the flow. They only have a weak coupling by affecting the viscosity or diffusivity (for 2-eqn models anyway). So as the coupling is weak then convergence can be looser and accuracy will not suffer (for most applications anyway).
|Thread||Thread Starter||Forum||Replies||Last Post|
|Extrusion with OpenFoam problem No. Iterations 0||Lord Kelvin||OpenFOAM Running, Solving & CFD||8||March 28, 2016 11:08|
|High Courant Number @ icoFoam||Artex85||OpenFOAM Running, Solving & CFD||9||January 3, 2012 09:06|
|Orifice Plate with a fully developed flow - Problems with convergence||jonmec||OpenFOAM Running, Solving & CFD||3||July 28, 2011 05:24|
|Differences between serial and parallel runs||carsten||OpenFOAM Bugs||11||September 12, 2008 11:16|
|Unknown error||sivakumar||OpenFOAM Pre-Processing||9||September 9, 2008 12:53|