Hi, @kirin, the inlet shape shouldn’t matter. I looked at you ‘my attempt’ setup, I presume you are just checking setup here? for vortex shedding, you need a transient simulation, which ‘my attempt’ isn’t. The first mesh is very good but for a transient is very expensive, have you tried running your second mesh as a transient simulation? This will be almost 10 times quicker than the first mesh per iteration and also allow you to run on fewer cores for efficiency. Since the cells are larger you might even get longer timesteps if you are using auto time stepping. Also on the second mesh, you may have to refine the wake to allow a detailed capture of the vortices.