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Problem in applying Gamma-Retheta transition model

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Old   November 6, 2012, 23:10
Default Problem in applying Gamma-Retheta transition model
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Mehdi
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dear friends;
hi, I face the problem in applying Gamma-Retheta transition model in my code. in fact, it started to converge, but after 2000 iteration, its results are not correct. as you can see figures, Cf is not correct and it should match with analytical turbulent Cf on flat plate after transition to turbulent regime.
I think the problem stems from the velocity profile, as you can see in second figure, velocity profile near flat plate doesn't have turbulent velocity profile shape. in fact, it is similar to Laminar profile and even the shape of the flow that face with adverse pressure gradient.
I guess problem comes from the intermittency equation. next figure shows intermittency in where above velocity profile was taken.
and amazingly, as you can see in K profile in next figure, code does not work and it has very strange shape.

I don't know why this happens. I have tried to find the reason of the problem, but I can not find any thing. the initial and boundary conditions for this case are :

Reynolds Number= 752536.0

Rmu (mut/mu)= 6
Tui in inlet= 3.1% , Tui in leading edge= 1.99%

Attached Images
File Type: jpg friction coef..jpg (21.1 KB, 9 views)
File Type: jpg velocity.jpg (51.4 KB, 8 views)
File Type: jpg intermittency.jpg (64.4 KB, 8 views)
File Type: jpg Kinetic Energy.jpg (22.2 KB, 6 views)
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Old   November 6, 2012, 23:48
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I should mentioned that I used Malan et al. and menter (2009) empirical correlation formula for Flength and critical momentum thickness Re and non of them provide good results.
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Old   November 13, 2012, 11:27
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Mehdi
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any idea which can fix the problem?
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