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Specifying the transition Reynolds and cfx's calculation of this number

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Old   April 3, 2011, 22:10
Default Specifying the transition Reynolds and cfx's calculation of this number
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Nick
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Hi,

My question is regarding the way the transition Reynolds number should be specified as a user defined parameter in the transition models. I read in other posts that the method CFX uses to define the length scale is thru the cube of the flow domain volume and averaged velocities. So I wonder how I can come up with a Re that is consistent with this method?

Suppose I estimate transition to occur at 1/5th of the chord on an airfoil from the leading edge. Should I simply use this length to calculate and specify Reynolds in the CFX model?

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Nick
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Old   April 4, 2011, 19:27
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Glenn Horrocks
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You can specify the transition location by many ways. Not sure if you can specify a Re number, hopefully you can.

But if you know where the transition is you can just define the intermittency and define this area as laminar and that area as turbulent. Much simpler.
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Old   April 5, 2011, 01:49
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hi, i am doing simulation of multiphase flows in stirred tanks using gas-liquid.. the problem is well defined but i get some solver errors.. POPDIR, MEMER, MAKDIR.. it says some files in the crash recovery file is locked.. how to get rid of this problem?
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Old   April 7, 2011, 02:31
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Post some more details of the error from the .out file Vidhya. The error could be numerous things. And please start a new thread as the topic of this thread has no relation to your problem.

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Luke
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