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Old   February 22, 2010, 10:35
Default Improving convergence ?
Jérémy Bulle
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I find that the convergence for my problem is slow. Here are the residuals :

My problems is set up like this :

Fluid = Air

Solver :
Not changed anything

Viscous :
Model = K epsilon realisable (No factors changed compared to standard)
Wall treatment : Enhanced since I want to resolve the boundary layer (I've check, max y+ = 1.4)

Boundary Conditions :
Inlet : Velocity : 7m/s
Outlet : Pressure : 0

Solve -> Control -> Solution
Changed the discretization like this :
Pressure : standard
Momentum : second
turbulent blabla : first
Turbulent blabla : first

Residuals :
Changed the absolute criteria to 1e-06

Thanks for your help, I can show you the mesh if it's needed
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Old   February 23, 2010, 03:09
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Maxime Perelli
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Your convergence isn't "slow". From my side your convergence is good.
You may try to change your URF, but it is just tunning in your case.
I give you a tipp: don't look just at you residuals for checking convergence. I would monitor a variable which is in your interest (for instance pressure at your inlet, or force on a body). Convergence occures once you get a stable monitor
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