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Simon February 11, 2005 07:03

Problems in convergence
 
Hi,

I have a problem concerning a transient calculation I am conducting. Even though I have sufficiently small time step size ( Courant number below 0.5 ), at every time step the .info file spits out error messages concerning the convergence of the equations, like this :

<<<<U-MOMENTUM EQUATION NOT CONVERGED>>>>

<<<<W-MOMENTUM EQUATION NOT CONVERGED>>>>

<<<<CONTINUITY EQUATION NOT CONVERGED>>>>

<<<<ENTHALPY EQUATION NOT CONVERGED>>>>

<<<<SCALAR EQUATION 1 NOT CONVERGED>>>>

<<<<SCALAR EQUATION 3 NOT CONVERGED>>>> I have increased the number of corrector stages but the problem persists. Any ideas? Thank you in advance.

Simon February 11, 2005 07:05

Re: Problems in convergence
 
It seems I made a mistake in my post, the error messages read : U-MOMENTUM EQUATION NOT CONVERGED W-MOMENTUM EQUATION NOT CONVERGED CONTINUITY EQUATION NOT CONVERGED ENTHALPY EQUATION NOT CONVERGED SCALAR EQUATION 1 NOT CONVERGED SCALAR EQUATION 3 NOT CONVERGED

Somnath February 12, 2005 06:27

Re: Problems in convergence
 
hi,

The same kind of error i got in one of my analysis. what i did i just decrease the residual tolarances and also increase the corrector stages from 20 to 30 and at the same time increase the number of sweeps. now that error is not there..U can try this also.

somnath

Simon February 14, 2005 06:36

Re: Problems in convergence
 
Thank you for the advice. I wiil try it out immediately.


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