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Old   September 6, 2004, 22:29
Default w - urgent
  #1
azmir
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Hi!

I was checking the monitored values of omega while running a k-w model. The w value seems to ever-increase while all others are decreasing. Is there a way to rectify this for k-w? Or should I ignore it? Is this due to free-stream w value?
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Old   September 18, 2004, 19:56
Default Re: w - urgent
  #2
Sheila
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How did you define your inlet w value? Check the following

VIST=DEN*TE/ED(omega)= 0.09*DEN*TE**2/ED(epsilon)

usually VIST and freestream turbulence is given.

If the above is not the problem, try decreasing relaxation factor.

Sheila
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Old   September 25, 2004, 02:05
Default Re: w - urgent
  #3
azmir
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Thank u! I resolved the increasing w monitored value by letting it run another 1000+ iterations more where it eventually came to rest. But, your pointer is interesting! Where would I put this calculated w value in star-cd actually?
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Old   September 28, 2004, 02:06
Default Re: w - urgent
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Sheila
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OK... understand your question from the other link now...

The values I mentioned are for INLET boundary condition.

Make sure your residual is low enough, the stopping of the changing of values does not necessarrily mean convergence.

Hope that helps. Sheila
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Old   September 28, 2004, 02:08
Default Re: w - urgent
  #5
Sheila
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BTW, when you are using k-w/SST models the w values have to be entered in the designated place of e. STAR will take these values as w.

Sheila
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Old   September 28, 2004, 02:26
Default Re: w - urgent
  #6
azmir
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Ah thank u very much! All the while I've been using only the TI & Length. Forgot about the option of k-e which is k-w in the kw-sst model!! I hope u'd find answers to your q's. Sorry I couldn't help u there. U're more advanced.
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Old   September 28, 2004, 02:48
Default Re: w - urgent
  #7
azmir
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Sorry, one last question! If I leave the turb. switch as TI & Length instead of k & E or w, will star-cd automatically convert the L into w?
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Old   September 29, 2004, 17:55
Default Re: w - urgent
  #8
Sheila
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I would assume so...
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