Dynamics of a Hydroelastic Oscillating Cylinder with Added Viscoelastic Damping for Passive Control of Vibrations

摘要

In the scope of flow around cylindrical structures, the vortex shedding phenomena are those that have attracted considerable attention from many mechanical and civil engineering domains. Since, these phenomena - dependent on a number of factors - may have disastrous effects in engineering practice, such as economic loss, damage of installations, loss of power-generating time, etc. This is a reason for which in the last decades, a great deal of effort has been devoted to the development of numerical and computational procedures for dealing with the problem of vortex shedding phenomena. Among the various new developments for dealing with the problem of vortex-induced vibration, the use of viscoelastic materials is considered as an interesting strategy, since they present great efficiency in mitigating vibrations levels at moderate application and maintenance costs. In this paper, the Immersed Boundary Method combined with the Virtual Physical Model is used to investigate the forces and response associated with the vortex-induced vibration of a rigid oscillating cylinder incorporating viscoelastic damping. In the context of fluid-structure interactions, an important issue addressed herein is the modeling procedure of the viscoelastic behavior in the time domain, which is performed by using a fractional-order constitutive model. After the presentation of the underlying theoretical foundations related to the various aspects of the numerical modeling procedure, numerical simulations with a viscoelastically damped oscillating cylinder performed in a wide range of oscillating amplitude and forcing frequency are presented and discussed aiming at demonstrating the influence of viscoelastic damping on the flow structure and fluid forces.