Experimental Study of Magnus Effect on a Rotating Projectile

A new experimental technique has been developed to measure the pressure distribution over the surface of a spinning wind tunnel model. The technique is unique in that all elements of the instrumentation, thus avoiding many of the technical problems and operational limitations associated with previous attempts to measure this effect. Surface pressure distributions were obtained for selected tip speed ratios for different angles of attack (5000rpm). The results obtained from the pressure profiles determine the Magnus forces and make it possible to interpret the boundary layer and the effects of separation. In this method, in addition to determining the Magnet force, its distribution on the model is also obtained. The results show that most of the Magnus force is created at the ends of the projectile. The validity of the data was established by comparing the integrated pressure values with directly measured balance data. Similar results were obtained by the numerical simulations and were compared with the experimental data. This new technique can be applied to a variety of model configurations and Mach number regimes.