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-   -   Fluent inviscid solution (http://www.cfd-online.com/Forums/fluent/118457-fluent-inviscid-solution.html)

ashishtbm May 28, 2013 05:01

Fluent inviscid solution
 
I am simulating a 2D cylinder under inviscid condition, but I am getting positive values of both lift and drag coefficient, while ideally both should be zero. I even did naca 0012 under inviscid condition but in this, lift coefficient is ok, but drag is still positive and is not reduced to zero. I want to know which model to be used and i what condition to to simulate ideal condition so that pressure drag becomes zero in my simulation?

sbaffini May 28, 2013 12:21

An ideal flow would give the results you expect. However, a numerically simulated inviscid flow carries all the numerical viscosity of the numerical method and it is impossible to avoid some numerical drag. For the cylinder case i expect no lift however, and it is possible that the flow field was not symmetric when you computed the lift.

yhy20081016 June 21, 2014 12:43

For the cylinder case, since there exists numerical viscosity, it is possible that the unsteady Karman vortex street occurs. If it happens, then the lift will not be zero.


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