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Old   May 6, 2004, 08:52
Default turbulent viscosity
  #1
habib hossainy
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hei, i am simulating a two-phase flow of air-water in a circular pipe and after som iterations it stops and the following is shwon,

turbulent viscosity limited to viscosity ratio of 1.000000e+05 in 9854 cells...

Error: Too many (0) VOF sub-timesteps. The velocity field is probably diverging. Please check the solution, and reduce the time-step if necessary.

I have reduced the time steps without any result, can anybody tell me what is wrong?

Thanks
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Old   May 6, 2004, 16:44
Default Re: turbulent viscosity
  #2
Pardeep
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what is the turbulence model ur using? What is the initial values of K and Epsilon(in case ur using K-E)?

That comment about TV limited ... means that ur Turbulence model is not working properly. Try initial values of K and Epsilon of the order of 10E-3 or 10E-4

I think that shud help ur case. Let me know if u try this?

Pardeep
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Old   May 7, 2004, 02:10
Default Re: turbulent viscosity
  #3
Pravin Naphade
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U r getting message that turbulent viscosity is limited to 1.00e10+05. that mean calculated ratio is more than this..since it is limited to above value u r facing the problem... In fluent

goto SOLVE....CONTROLS.....LIMITS .. in limits increase the maximum turbulent viscosity ratio to 1.0e10+07 and try

best luck next time!
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Old   May 8, 2004, 00:11
Default Re: turbulent viscosity
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Mukkarum
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I am also getting same messege. May you tell me the formula to calculate turbulent viscosity. Thanks
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Old   May 10, 2004, 20:07
Default Re: turbulent viscosity
  #5
co2
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The turbulent viscosity ratio is defined as following: turbulent viscosity --------------------- laminar viscosity
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Old   May 11, 2004, 05:53
Default Re: turbulent viscosity
  #6
zxaar
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how about makign the grid little refined!!!!

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Old   May 11, 2004, 07:53
Default Re: turbulent viscosity
  #7
zachi
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is your problem still existing or did some changes make your simulation working again?

regards,

zachi
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