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Turbulence model for land-scape?

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Old   May 2, 2002, 06:06
Default Turbulence model for land-scape?
  #1
Anne Rasmussen
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Hi,

I am initiating a small research project conserning siting of wind turbines in complex landscape structures.

Does anyone have experience to share - choice and setup of turbulence model are of particular interest

/Anne
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Old   May 2, 2002, 07:37
Default Re: Turbulence model for land-scape?
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Jens Chr. Bennetsen
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Hi,

When simulating wind environment it is very important to have the right boundary layer profile together with the turbulent kinetic energy profile. And also surface roughness is important.

AS for the turbulence models, as long as you do not use standard k-eps. It works okay, but is know for its short comnings. I have often used RNG which I have proven to be quite good also when comparing to exsperimental data.

Also remember that termal effect can change the wind profile during the day. So if you have large termal gradient during the morning and afternoon, large differences can be seen.

Kind Regards

Jens
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Old   May 2, 2002, 08:45
Default Re: Turbulence model for land-scape?
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Anne Rasmussen
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Hi,

when using the RNG model are any of the coefficients in the model changed from the default values in order to maintain a sufficient kinetic energy level?

And is the model supplemented with a boundary model?

Sincerely Anne
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Old   May 2, 2002, 08:53
Default Re: Turbulence model for land-scape?
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Jens Chr. Bennetsen
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Hi agian

No default values has been used. The MMK k-eps model could also be used.

Regards

Jens
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Old   May 2, 2002, 09:04
Default Re: Turbulence model for land-scape?
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Anne Rasmussen
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Hi,

do you mean "no default values" or " no - default values has been used" ?

Sincerely Anne
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Old   May 2, 2002, 16:15
Default Re: Turbulence model for land-scape?
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Jens Chr. Bennetsen
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Yes

I have just used the default values for the RNG model.

The has been a lot of work done by Mochida and Murakami on wind engineering with different turbulence models.

Regards

Jens

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