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intermittency of transition SST model

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Old   August 29, 2013, 11:20
Default intermittency of transition SST model
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Hi,

In my case, i want to use the transition SST model or the transition k-kl-omega model. But i don't know how to determine the intermittency and the laminer kinetic energy.

Does someone know how to calculate them?

Thank you.
Steven
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Old   August 29, 2013, 13:05
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You dont need these quantities.
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Old   August 30, 2013, 03:20
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Quote:
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You dont need these quantities.
Thank you for your reply.
So what should i fill in the blank?
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Old   August 30, 2013, 05:24
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Are you talking about transition models of Fluent? If yes then you dont need to input any parameters for these models except turbulence length scale and turbulence intensity if you have info about them.

If you dont have info about length and intensity then you can use these parameters (can be used in parametric study) :

For turbulence length scale you take it as 30% of chord length and turbulence intensity can be taken as < 1% for low distrubence such as in wind tunnels, 1-5% in normal free stream conditions and >5% in highly disturbed upstream flow.
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Old   September 2, 2013, 07:59
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Ok, thank you, so i can i will have a try.
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Old   September 2, 2013, 08:44
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Quote:
Originally Posted by Far View Post
Are you talking about transition models of Fluent? If yes then you dont need to input any parameters for these models except turbulence length scale and turbulence intensity if you have info about them.

If you dont have info about length and intensity then you can use these parameters (can be used in parametric study) :

For turbulence length scale you take it as 30% of chord length and turbulence intensity can be taken as < 1% for low distrubence such as in wind tunnels, 1-5% in normal free stream conditions and >5% in highly disturbed upstream flow.
hello, i still have a question. how can i judge whether my results are correct? for example, when i use k-epsilon standard-wall function, if my yplus are between 30 and 300, i'ill accept the results.
Thank you.
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