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Low Reynolds number k-E Turbulent Model

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Old   July 2, 2002, 07:12
Default Low Reynolds number k-E Turbulent Model
  #1
Sohail
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Hello,

Can any body please help me how to model low reynolds number K-E Turbulent Model in Fluent because the defalt K-E Turbulent Model used by Fluent is not valid for Low raynolds number flow. Thanks for your valuable suggestion
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Old   July 2, 2002, 12:37
Default Re: Low Reynolds number k-E Turbulent Model
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lax
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I am having same question in my mind. Can you just tell me, Re number u are having in your problem.

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Old   July 2, 2002, 17:03
Default Re: Low Reynolds number k-E Turbulent Model
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Steve
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A Low Reynolds number model is a turbulence model that integrates through the viscous sub-layer down to the wall (i.e. the locally low Reynolds number region of the flow). It is still only applicable to high Reynolds number flows where the flow is fully turbulent. It is not a model for solving flows with low global Reynolds number. For that you need a transition model and I don't think that a good universal transition model exists.
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Old   July 2, 2002, 23:37
Default Re: Low Reynolds number k-E Turbulent Model
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Greg Perkins
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There is the low Re model in Fluent. Activate it through the text interface at:

/define/models/viscous/turbulence-expert low-re-ke yes

Greg
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Old   July 3, 2002, 02:45
Default Re: Low Reynolds number k-E Turbulent Model
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Karl
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There are six models available through text command:

define/models/viscous/low-re-ke-index

Index: 0...Abid

1...Lam-Bremhorst

2...Launder-Sharma

3...Yang-Shih

4...Abe-Kondoh-Nagano

5...Chang-Hsieh-Chen

Fluent uses number 3 as default.
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Old   August 9, 2009, 14:30
Smile Low Re
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Shengyi Wang
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Quote:
Originally Posted by Greg Perkins
;101560
There is the low Re model in Fluent. Activate it through the text interface at:

/define/models/viscous/turbulence-expert low-re-ke yes

Greg
Hi~ Greg:

Very good information. Thank you!

But it seems that the range of low Re has never been mentioned in the Fluent mannual. Do you know what range of Re can be classified into low Re in Fluent?
Thanks a lot.
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Old   February 2, 2010, 12:01
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Hi Greg,

I tried several times the text command, but gives me "invalid command". Can you help me?
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Old   July 26, 2011, 15:11
Default greg's command
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/define/models/viscous/turbulence-expert/low-re-ke yes

there is a "/" between turbulence-expert and low-re-ke yes.

this should get u to the command
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Old   July 27, 2011, 03:30
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It works but just for one of the mentioned turbulence models
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Old   December 13, 2011, 06:08
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sona cs
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Hi Greg

Really good information.Thanks alot.
Is Lai and So model also available in Fluent?...
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Old   December 16, 2011, 04:34
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before you select low RE k-e model from text command you need first to choose standard k-e from the menu define>model> viscus else you cannot see the low RE k-e model in text command.
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Old   December 16, 2011, 09:00
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Hi Kbaker

Thanks for your reply.


I tried the following command after selecting define/models/viscous/k-epsilon standard,

/define/models/viscous/turbulence-expert> low-re-ke
Enable the low-Re k-epsilon turbulence model? [yes] yes

/define/models/viscous/turbulence-expert> low-re-ke-index

but it is not showing the available Low Re models.
Hope you can help me.
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Old   January 7, 2013, 02:01
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There are six models available through text command:

define/models/viscous/low-re-ke-index

Index: 0...Abid

1...Lam-Bremhorst

2...Launder-Sharma

3...Yang-Shih

4...Abe-Kondoh-Nagano

5...Chang-Hsieh-Chen

Fluent uses number 3 as default.


I was given in one of the posts that the above low re k-e models are available in FLUENT. Can someone pls from where these models came from. WHich book or material describes its significance in FLUENT
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Old   December 3, 2013, 12:59
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Hello everyone. Can anybody point me how to turn on the low-re-ke turbulence model in Fluent 14?

In the text user interface there is no such position in /define/models/viscous/turbulence-expert. If I enter 'help' there is a note that says: "These followed by "*" are currently disabled" and below there is among others low-re-ke followed by "*".

How to turn it on? Is it possible? Thanks.
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