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BB May 31, 2001 22:12

turbulent vicosity limited errors
 
What causes 'turbulent viscosity ratio limited errors'???

my grid is scaled properly, but running k-e model always yields this error! Any ideas???

BB May 31, 2001 22:12

Re: turbulent viscosity limited errors
 

Evan Rosenbaum June 1, 2001 12:13

Re: turbulent vicosity limited errors
 
See under the Solve-Control-Limits menu.

reza June 4, 2001 16:16

Re: turbulent vicosity limited errors
 
hi first of all check the inlet k and epsilon or equivalently turbuent intesity and , try to set some reasonable values for these parameters. second try to check the geometry for very sharp edges or very small surfaces made by mistake. last chack the mesh interfaces. bye reza

Chetan Kadakia June 7, 2001 22:54

Re: turbulent vicosity limited errors
 
BB, have you solved this problem yet. Are you sure what you get is an error... I think it is just a notification. Like Evan said, go to the solve-monitors-limits. These are limiting max/min values that are allowed. So if in a cell, a calculation finds something beyond the limits that were set, wether they are the default values or if they are use defined, you will get a message, and the value will be set at the limiting value (not the calculated value).

First you should check to see if the default limits are reasonable. Then do some other checks like the ones Reza spoke of. If you are still having trouble please respond with detail of your problem, mesh, and solution.

-Chetan K.

BB June 8, 2001 05:46

Re: turbulent vicosity limited errors
 
Thanks for your replies

I will get on to this very soon. Found a possible problem since one of my 54 interfaces did not match and it was due to a mindslip when linking faces. This could have been a reason...no sharp edges in the mesh...just some areas of small gaps with a very fine mesh.

In your experience, how does changing viscosity ratios change the solutions??

reza besharati June 9, 2001 00:27

Re: turbulent vicosity limited errors
 
hi in my experience i never could get convergence in default settings of course with the notification or error message repeating every step of iteration, specially it was apparent that countinuity residuals were never less than order of 10^-1. take care reza


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