Magnus effect on a rotating sphere at high Reynolds numbers

Aerodynamic force measurements and a flow field survey were carried out on a sphere rotating perpendicular to the flow direction in order to investigate the effect of the rotation on the flow parameters at Reynolds numbers in the range of 0.68×105<ReD<5.07×105. Experiments were performed using a support system based on the classic approach of a rod driving the sphere. Additionally, an innovative rear sting support was developed where the sphere was split into two hemispheres that were driven by a motor inside them. The results show considerable changes of the mean force coefficients with Reynolds number ReD and spin parameter SP, which can be attributed to the altered boundary layer separation. These changes also lead to significant changes of size and orientation of the wake zones. A negative Magnus effect occurs in a wide range of Reynolds numbers ReD and spin parameters SP.