[Jennifer Von]

Hi everyone,

I'm running a 3D cylinder simulation in FLUENT with a Re of 100,000. I've used a Transition SST model with a time-step size of 5e-04 and 200,000 time steps. Pressure and velocity coupled scheme is PISO. y plus <1 ，so does that mean mesh is ok? I'm trying to obtain the drag coefficient from this simulation

The results I've obtained shows an oscillatory motion, with the Cd value hitting a peak of 1.1 midway before falling back to 0.7 at the end of the 200,000 time steps.

I used k-e model/SST but the results are not good.


Can anyone tell me why has this occurred? What do I need to do for the Cd values to be stablised?

Thanks!

Regards,
Jennifer