Vortex-induced vibrations of a flexible cylinder at large inclination angle

Vortex-induced vibrations of a flexible cylinder at large inclination angle.

The free vibrations of a flexible circular cylinder inclined at 80° within a uniform current are investigated by means of direct numerical simulation, at Reynolds number 500 based on the body diameter and inflow velocity. In spite of the large inclination angle, the cylinder exhibits regular in-line and cross-flow vibrations excited by the flow through the lock-in mechanism, i.e. synchronizatio...

Vortex-induced vibrations of a long flexible cylinder in shear flow

We investigate the in-line and cross-flow vortex-induced vibrations of a long cylindrical tensioned beam, with length to diameter ratio L/D=200, placed within a linearly sheared oncoming flow, using three-dimensional direct numerical simulation. The study is conducted at three Reynolds numbers, from 110 to 1100 based on maximum velocity, so as to include the transition to turbulence in the wake...

Perturbation of Vortex Induced Vibrations on a Square Section Cylinder

This paper addresses the vibration of a square section cylinder due to the alternate vortex shedding at moderate Reynolds number (3500). The numerical investigation is focused on the perturbation of the vortex shedding in order to decrease the amplitude of the vibrations at lock-in. By analyzing the unsteady flow results, we show that a control technique spatially localized at the surface of th...

Vortex-Induced Vibrations of an Inclined Cylinder in Flow

A novel reduced order model for vortex induced vibrations of long flexible cylinders

In this manuscript the development of a reduced order model for the analysis of long flexible cylinders in an offshore environment is proposed. In particular the focus is on the modelling of the vortex induced vibrations (VIV) and the aim is the development of a model capable of capturing both the in-line and cross-flow oscillations. The reduced order model is identified starting from the resul...