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Old   September 10, 2004, 21:50
Default negative volume
  #1
wak
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Hi..

Anyone ever facing this ..

*** WARNING #090 *** VALUE ELOG*YPLUS OR LOG*EFFVIS/(CAPPA*VISCOS) IS LESS THAN 1.1 AT 149 CELLS.UPLUS=YPLUS LAW IS USED. IF THIS SITUATION PERSISTS, INCORRECT RESULTS MAY BE OBTAINED.

After several iteration my calculation stopped, because star detect a negative volume. My case is transient sliding mesh.

Thanks in advance..

^ ^ |
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Old   September 12, 2004, 07:54
Default Re: negative volume
  #2
Richard
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The warning #090 is telling you that your mesh is too fine for the high Re turbulence model which you are using. This is just a question of modelling accuracy. You can choose whether to ignore it, change the mesh or change the turbulence model.

The negative volume is something else: this is telling you that your mesh motion is wrong and is corrupting the mesh. Check your mesh motion commands. You could do a mesh preview run: this will highlight the problem faster than you doing a full analysis.
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