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A silly question about turbulent flow

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Old   September 3, 2013, 14:42
Default A silly question about turbulent flow
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I wonder why we sometimes can apply steady state in the modelling of turbulent flow

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Old   September 3, 2013, 15:11
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Because in such cases (Reynolds-averaged Navier Stokes) you are solving for the mean quantities from the Reynolds averaging. These quantities are considered to be steady, since any time dependency has been averaged out.
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Old   September 15, 2013, 15:35
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Quote:
Originally Posted by itsme_kit View Post
I wonder why we sometimes can apply steady state in the modelling of turbulent flow

Many thanks

It's not a silly question ! It's very clever,
it is indeed paradoxical as turbullent flow are strongly unsteady !!

agd gave the right answer!!
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Old   September 15, 2013, 21:11
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Quote:
Originally Posted by itsme_kit View Post
I wonder why we sometimes can apply steady state in the modelling of turbulent flow

Many thanks
some time , when the boundary is moving , then we use the unsteay governing equations.
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