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harly November 18, 2008 16:38

Hi, I have a question: I

I have a question:

I am trying to evaluate lift/drag from a square cylinder and I am struggling with the results I get.

I read that OpenFOAM produces fairly good results for such problems - but I also read, that OpenFOAM gives best results "dimensionfree" - and therefore most of the people are using v=1 and nu = "equivalent to get wanted Re number".

I need to use properties of air to be able to compare my results.

so I picked

Ux = 0.3

nu = 1.5e-5

and in forces/forceCoeffs(to calculate lift/drag in OF1.5)
rho = 1.2

equals Re = 20000

But my results are very bad, e.g Lift more than twice as it should be.
Any Ideas? What properties do you use for air ? And how do you get the right Coefficients ?

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