ИСТИНА

Vortex-induced vibrations (VIV) is a phenomenon of self-exciting oscillations of elastic, or elastically mounted rigid bluff bodies exposed to in a gas or fluid flow. This sort of oscillations can be used to harvest electric energy from the kinetic energy of air or water flow. This fact determines the great practical significance in the study of this phenomenon. In this work, an experimental study of resonant self-oscillations of a circular cylinder on a transverse flexible beam was carried out. In contrast to similar works with a similar configuration of the model that performs transverse translational oscillations, was discovered previously unexplored VIVs type in which the cylinder rotates around the cantilever support. Experiments were performed in the Institute of Mechanics of Lomonosov Moscow State University in a wind tunnel A-10 with an Eiffel chamber and an open test section. The Reynolds number range based on cylinder external diameter corresponding to the response region was (5–25)×10^3. In the present experiments, the maximum oscillation amplitude 0.80 was obtained. For a torsional resonance state, observed here for the first time, the characteristic reduced speed range is 6.9..7.35, which corresponds to Strouhal number 0.144..0.136.