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Curvature Effects using the Standard K Epsilon Model

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Old   October 19, 2010, 02:00
Default Curvature Effects using the Standard K Epsilon Model
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ralph
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Hi,
I am simulating a flow over 2d hills. Curvature pretty much comes into the equation here. There will be an extra strain rate dv/dx. I am using the k epsilon model to run my simulation and playing with the curvature correction term does not exactly give accurate results. The maximum value allowed is 1.25. I am thinking about incorporating the richardson number into the k epsilon model. but since the richardson number is a function of dv/dx and du/dy, i would need to have a Cmu that is not invariant. I understand that CFX does not have the realizable k epsilon model in its list of models so this is a bugger. i have tried inputting a CCL function into Cmu but it returns an error message saying that i cannot input variables when defining Cmu. Any suggestions how i can tackle the effects of curvature?

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Old   October 19, 2010, 17:51
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Glenn Horrocks
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The SST model has some curvature correction stuff available. Have you tried that?
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Old   October 19, 2010, 20:53
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Hi Glenn,
i am trying to work with the k epsilon model only because it is pretty much the bread and butter of turbulence modelling. Also, my project is based on the k epsilon model. Is there a way I can edit the existing turbulence models in Ansys CFX. And by that i do not mean just changing the constants. i want to include the richardson number / curvature to the kinetic energy and dissipation equations. It would be awesome if i can just add on the terms to the preexisting models in CFX. Please advise.

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Ralph
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