NONPERIODIC AND CHAOTIC VIBRATIONS IN A FLOW-INDUCED SYSTEM

A flow induced system, consisting of an elastically mounted body with a pendulum attached, is considered here. The stability of the semi-tri vial solution, representing the vibration of the body with the non-osc illating pendulum, is investigated, The analytical investigation shows that at a certain flow velocity, higher than the critical one, the pe ndulum begins to oscillate due to autoparametric resonance. For a conv enient tuning, the vibration of the system can be substantially reduce d. The analysis of both semi-trivial and non-trivial solutions is comp lemented by numerical integration of the differential equations of mot ion. A mapping technique based on Poincare section, suitable for inves tigating the non-periodic vibrations occurring at higher flow velociti es, is proposed.