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Laminar flow over a cylinder_lift and drag coefficient

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Old   February 18, 2014, 08:29
Post Incorrect lift coefficient for laminar flow over a cylinder
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Meher
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Hello all,

I am trying to match my results of drag and lift coefficients for flow over a cylinder with a standard benchmark result. After making few attempts, I could able to match the result only for drag coefficient. But, the lift coefficient result is 10 times more than the desired result. So, it is quite clear that something is seriously wrong with the set-up. Please look into my case here and help me with your suggestions.

Benchmark Case BC's are as follows:
Input: Re=20 ; nu = 0.001 ; initial velocity = 0.2 m/s ; Domain = 2D ; incompressible ; velocity-inlet ; do-nothing boundary conditions for outflow ; no-slip condition for top and bottom walls.
Output: Cd = 5.57 ; Cl = 0.01

The geometry has been made in icemcfd and imported into openfoam. I have used simplefoam solver. Though the simulation is getting converged, I could see time step continuity errors. How much does this effect the final result?

Reference area for cylinder = diameter of cylinder * span-wise length (in case of 2D).
Since OF converts 2D domain into 3D before solving it, how to determine the span-wise length? I tried to input the length of one grid cell (taken by OF) as span-wise length. I have uploaded important files of the case. Please give your feedback.

forceCoeffs.txt

fvSchemes.txt

fvSolution.txt

p.txt

U.txt

Thanks,
Meher.
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Last edited by ssmeherk; February 20, 2014 at 06:11. Reason: title not reflecting the content of my post
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cylinder flow, drag coefficient, laminar, lift coefficient

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