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Is it possible the velocity profile changes in the fully-developed turbulent flow?

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Old   July 9, 2020, 16:46
Default Is it possible the velocity profile changes in the fully-developed turbulent flow?
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Hello, I am a new in ANSYS fulent, and I have a question, the model is air flowing in pipe. When I input a parabolic equation at the inlet for a laminar flow, the laminar flow is a fully-developed flow with a constant velocity profile. But when I am using the same equation for the turbulent flow (k-e standard), unlike the laminar flow, the turbulent flow does not show a constant velocity profile.
So for a fully-developed turbulent flow, is it possible that the velocity profile is changing alone axial direction? If is possible, why it changes? If it is impossible, how may I setup a fully-developed turbulent flow with constant velocity profile?
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Old   July 10, 2020, 13:22
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The fully developed velocity profile isn't parabolic, parabolic is only for laminar. That's why your velocity profile changes from the parabolic at the inlet, to the eventually turbulent profile.


If you prescribed the correct turbulent velocity profile at the inlet, it would be nearly constant across the pipe length. Actually you need to also prescribe the k and epsilon profiles but these are much more minor than the velocity profile.
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Old   July 11, 2020, 04:28
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thank you very much!
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