Experimental investigation of rotational vortex-induced vibrations of a circular cylinder attached to an elastic beam

Abstract

We study a rigid finite-span cylinder mounted on an elastic cantilever beam transversely to the direction of subsonic airflow in a wind tunnel. The purpose is to identify and analyze various types of vortex-induced resonant excitation for use in energy harvesters based on vortex-induced vibrations. The results of the experimental study show that in contrast to similar works with a similar model configuration that performs two-dimensional translational oscillations, we have discovered a previously unexplored three-dimensional type of VIV in which the cylinder rotates around the cantilever support. It has been experimentally proven that a lock-in regime exists for this type of oscillation, and the von Kármán vortex streets, generated by upper and lower parts of the cylinder, are shifted in phase by π. We conduct a detailed analysis of this new type of VIV.