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Kalle December 29, 2008 13:26

turbulent viscosity limited
 
Hello,

I am running a large case in segregated solver and keep getting a warning saying "turbulent viscosity limited in xxx number of cells". This number grows pretty constantly for each iteratrion step until i get a floating point exception. The flow field was initialized from a previous run with a slightly different geometry. So there might be cells with impropriate initialization. I tried adjusting the relaxation factors but it just slowed the divergence down a bit. What could cause this problem and how could I solve it?

Thanks

anon December 29, 2008 14:14

Re: turbulent viscosity limited
 
Troubleshoot by plotting turbulent viscosity and see where the extreme values lie. If it's at the location of modified geometry, then try clearing the solution and re-calculating.

anon December 30, 2008 15:43

Re: turbulent viscosity limited
 
Are you ramping CFL #? It might be already ramped up after the 1st simulation, so reset it to a lower value after replacing geometry.


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