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Transition k-kl-omega parameters at inlet

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Old   May 10, 2012, 10:47
Default Transition k-kl-omega parameters at inlet
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Hi!
I'm testing Transition k-kl-omega turbulence model. I was told that this model is very sensitive to initial parameters at flow inlet. So at boundary conditions (in my case pressure inlet) I have to input the value of laminar kinetic energy (kl), but i can`t find any equation in user manual which will help me to estimate this value.
Has anybody got information obout estimating of kl for this turbulence model?
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Old   May 11, 2012, 03:03
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Hello! I'm interested in this problem too.
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Old   May 11, 2012, 04:14
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I have found some information. In Fluent additional materials it is written that this parameter should be always equal 10^-6. Is it correct?
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Old   May 11, 2012, 04:39
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The only parameter which is important for transition model is the turbulence intensity. 2nd less important parameter is the length scale (in some papers they give value of 0.3 chord as length scale.) but it has little effect as per recent studies(I can send you papers)


Edit : instead of 0.3 chord the correct formula is 0.03 chord or 3% of chord
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Last edited by Far; May 11, 2012 at 06:08.
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Old   May 11, 2012, 05:58
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Quote:
The only parameter which is important for transition model is the turbulence intensity. 2nd less important parameter is the length scale (in some papers they give value of 0.3 chord as length scale.) but it has effect as per recent studies(I can send you papers)
Ok, thanks for information. Than I have another question about this model: is estimation of turbulence intensity and length scale the same as for another turbulence models?
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Old   May 11, 2012, 06:06
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same but for some purpose.

In other models turbulence intensity has no impact (as you are solving the problem fully turbulent). Whereas in transition models increasing/decreasing the turbulence intensity change the behaviour of transition from laminar to turbulent state.
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Old   May 11, 2012, 06:24
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Quote:
Originally Posted by Far View Post
same but for some purpose.

In other models turbulence intensity has no impact (as you are solving the problem fully turbulent). Whereas in transition models increasing/decreasing the turbulence intensity change the behaviour of transition from laminar to turbulent state.
Ok, thank you very much. I will try different initial turbulence intensity to see the change of transition zone behaviour.
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Old   May 11, 2012, 06:38
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pm your email id and I shall send you the latest papers so that you get the flavour of it.
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Old   May 11, 2012, 11:27
Default Where did you find the information?
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Quote:
Originally Posted by ticsh View Post
I have found some information. In Fluent additional materials it is written that this parameter should be always equal 10^-6. Is it correct?
Hi,
Where did you the information? I can't find much information in the help documents.

Sheng
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Old   May 11, 2012, 12:37
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Hi,
Where did you the information? I can't find much information in the help documents.

Sheng
At Ansys Costumer Portal
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Old   February 21, 2014, 10:45
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Quote:
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pm your email id and I shall send you the latest papers so that you get the flavour of it.
Could you please email me the papers:

ranamath06@gmail.com
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Old   February 21, 2014, 11:09
Thumbs up here you go :)
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Shared for every one.

https://dl.dropboxusercontent.com/u/...tionpapers.zip
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Old   February 21, 2014, 12:29
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Sorry, this link is not working.
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Old   February 22, 2014, 13:04
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please check it again...
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