Vortex-induced vibration in an one degree of freedom cylinder with structural nonlinearities

Abstract

Vibrations induced by fluid-structure interactions are frequent and harmful, as serious structural failures can happen even in reinforced structures. Particularly, structures with cylindrical shape are widely employed in engineering, for example, landing gear in aircraft, bridge pillars, chimneys, transmission lines and especially in the extraction of oil from under sea. Pipelines for extraction of petroleum and gas on offshore platforms are exposed all the time to numerous conditions of agitation of the sea water and mainly, intense e continuous maritime currents. Such pipes, known as "risers" are exposed, at certain conditions of maritime current velocity, vibrations that can be reach high amplitudes, leading to possible serious damages, including oil spills that often result in both immediate and long-term environmental damage. The understanding of aeroelastic phenomenon that leads to the emergence of these vibrations has been in the focus of the scientific community in the recent years, mathematical models based on computational fluid dynamics remain challenging, even with the computational development of the recent decades. Reduced-order models become therefore important, both for understanding and for the development of techniques to control those vibrations. In this research project, it is proposed the implementation of an empirical reduced-order model with one degree of freedom, transverse to the freestream velocity, including possible nonlinear structural effects. An experiment should validate the proposed model. The results of this present research model may be useful on development of more accurate empirical models, including important nonlinear effects that certainly occur in the real world.