forces on body in oscillatory flow
 

Hi,
I am interested in modelling oscillatory flow over a cylinder. I have manged to successfully model and validate the oscillatory flow using the 'uniformFixedValue" boundary condition as per

https://www.cfd-online.com/Forums/op...-velocity.html

Following that, I moved to including the cylinder in the oscillatory flow. The simulation runs just fine but when I look at the forces (drag and lift), it seems that the drag matches the experimental data very well but the lift does not make any sense. I expected the lift to be always positive and also smaller amplitude than what is predicted by the model.

I am pretty sure the simulation is correct but the issue should just be in the force estimation (such as: change of pressure sign due to flow reversal, estimating and using the dynamic pressure in pimpleFoam, ...) but cannot figure out how to resolve this.

I have attached a graph of results. U is the flow velocity. My simulation case can be downloaded from

https://drive.google.com/open?id=1n5...vE5Nd0P0svDXe-

I would really appreciate any feedback/comments.

Thanks
Ashkan

I have answered this in

https://www.cfd-online.com/Forums/op...tml#post688773

in case someone finds it useful.