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Tutorial 21: Turbulence models

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Old   April 20, 2009, 15:54
Default Tutorial 21: Turbulence models
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Hi, I want to use a turbulence model in Tutorial 21, however in the help is written:

While standard two-equation models, such as the k-ε model, provide good predictions for
many flows of engineering interest, there are applications for which these models may not
be suitable. Among these are:
• Flows with boundary layer separation.
• Flows with sudden changes in the mean strain rate.
• Flows in rotating fluids.
• Flows over curved surfaces.


Is the k-e model suitable for this application, or is another model recommended?

Hope to get your advice.
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Old   April 20, 2009, 18:49
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Hi,

It depends on what you are trying to get out of the simulation. If you are looking for the force on the plate then k-e should be fine. If you are looking for the size of the wake region behind the plate it is not.

These days the general purpose, first guess turbulence model is usually SST. It has a wider range of applicability than k-e - but still cannot model everything.

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Old   April 20, 2009, 18:55
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Hi

RNG k-e model is good to predict flow separation. try to get this reference:
Hyun S., Kleinstreuer C. (2001). Numerical simulation of mixed convection heat and mass transfer in human inhalation Test chamber. International Journal of heat and mass transfer, vol. 44(12), pp2247-2260

Regards

Mazen
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Old   April 20, 2009, 19:34
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Thanks for your replies.
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Old   April 24, 2009, 05:25
Default wind rotor blade simulation
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Hi, everyone:

Can I use the Turbogrid to mesh the flow field of a wind turbine blade?

I know the Turbogrid and ICEM can mesh an internal flow turbomachine easily such as gas turbine and water turbine. But I'm not sure whether it can mesh an external flow rotor like wind turbine. Does anyone has some experience and give me some advice?

Thank you!
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