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low re k-e models/ ske with ewt

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Old   April 16, 2010, 14:08
Default low re k-e models/ ske with ewt
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gina
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please as there a difference between the standard k-e models with Enhanced wall treatement and low k-e models!

thank you to answer me
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Old   April 17, 2010, 04:11
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there is some diffrences between the two models.
your question is a thematic question.
low reynolds models are disigned for low reynolds and are better than common models in suphisticated situations.
plz clear your requisite.
thanks.
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Old   April 17, 2010, 04:16
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enhanced wall treatment is a appropriate method for resolving the flow structure near th a wall.
in fluent for a model u can choise 3 type of wall treatment.
and in fluent existed 3 version of K-e midel i recommend you to apply RNG model for computing the flow structure and behaviore.
because its time consumption is a little more than STD k-e but it is better for flow prediction.

now:

ok we r u from?
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Old   April 18, 2010, 13:24
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Quote:
Originally Posted by heidar View Post
there is some diffrences between the two models.
your question is a thematic question.
low reynolds models are disigned for low reynolds and are better than common models in suphisticated situations.
plz clear your requisite.
thanks.
thank you for your answer heidar,
for the study of turbulent flow in fluent and near the wall, I use the standard ke model with enhanced wall treatment. I want to compare with Low Reynolds ke model, but with this model there is no treatment associate near the wall !? why? can this model solves the flow near the wall!? and this model must to requir specific number of cells near the wall?

thanks
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Old   April 19, 2010, 00:32
Default heidar
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hi gina
what is youre low reynolds model?
if you choose K-e turbulence models there is three wall treatmens that could be associate by the model to resolve the near wall flow structure.

if your choice is K-w the fluent automatically choose wolf stein one equation model as its wall treatment affair.
the automatic choosed wall treatment in SST and STD k-w models is equal by Enhanced wall treatment in wall treat for K-e models.

zero killed don't be woryy
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Old   April 19, 2010, 09:46
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Quote:
Originally Posted by heidar View Post
hi gina
what is youre low reynolds model?
if you choose K-e turbulence models there is three wall treatmens that could be associate by the model to resolve the near wall flow structure.

if your choice is K-w the fluent automatically choose wolf stein one equation model as its wall treatment affair.
the automatic choosed wall treatment in SST and STD k-w models is equal by Enhanced wall treatment in wall treat for K-e models.

zero killed don't be woryy
Hi Heidar,

I will to use Abe-Kondoh-Nagano model for low reynolds ke, because i will to study heat transfer...
you have not answer for my question please, why with low re ke model there is not near wall treatment?!

"there will be a dead and Fluent will be the killer ... the dead will be me"
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Old   April 20, 2010, 09:09
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dear gina

what is your fluent's version?
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Old   April 20, 2010, 15:50
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dear gina

what is your fluent's version?

hi, heidar,
i use FLUENT 6.3...
for my question about near wall treatment with low Re model, i found that this model dont need a treatment because he compute the entire boundary layer including the viscous sub-layer
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Old   April 21, 2010, 06:53
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be successfull
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Old   May 21, 2010, 09:48
Default ke model with EWT and low re model
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please I want to know, what is the diference between solving a flow with the standard ke model and enhanced wall treatement and resolving the flow with low Reynolds model?????????
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Old   February 15, 2012, 16:36
Thumbs up some differences
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1- standard k-w uses wall function and your low reynolds number solve a two equation model, hence, low reynolds solution is more relieble
2- low reynolds is more time consuming because you should make the mesh dense every where
3- LRM is a modern model
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