Vortical structures in a shallow wake of the flow around a confined cylinder at Re =3750

We study the flow over a cylinder placed between two parallel rigid walls using Large - eddy simulations. The Reynolds number based on the inflow velocity and diameter of the cylinder is 3750 corresponding to the subcritical regime with laminar separation.The comparison of the time - averaged flow patterns shows very good agreement with experiments.The unsteadiness of the recirculating bubble features the low - frequency modulation observed for the first time.