An Analytical Mechanics Framework for Flow-Oscillator Modeling of Vortex-Induced Bluff-Body Oscillations

An Analytical Mechanics Framework for Flow-Oscillator Modeling of Vortex-Induced Bluff-Body Oscillations

Author: Sohrob Mottaghi

Publisher: Springer

Published: 2019-08-08

Total Pages: 245

ISBN-13: 3030261336

DOWNLOAD EBOOK

This self-contained book provides an introduction to the flow-oscillator modeling of vortex-induced bluff-body oscillations. One of the great challenges in engineering science also happens to be one of engineering design – the modeling, analysis and design of vibrating structures driven by fluid motion. The literature on fluid–structure interaction is vast, and it can be said to comprise a large fraction of all papers published in the mechanical sciences. This book focuses on the vortex-induced oscillations of an immersed body, since, although the importance of the subject has long been known, it is only during the past fifty years that there have been concerted efforts to analytically model the general behavior of the coupling between vortex shedding and structural oscillations. At the same time, experimentalists have been gathering data on such interactions in order to help define the various regimes of behavior. This data is critical to our understanding and to those who develop analytical models, as can be seen in this book. The fundamental bases for the modeling developed in this book are the variational principles of analytical dynamics, in particular Hamilton’s principle and Jourdain’s principle, considered great intellectual achievements on par with Newton’s laws of motion. Variational principles have been applied in numerous disciplines, including dynamics, optics and quantum mechanics. Here, we apply variational principles to the development of a framework for the modeling of flow-oscillator models of vortex-induced oscillations.


Vortex Methods: Selected Papers Of The First International Conference On Vortex Methods

Vortex Methods: Selected Papers Of The First International Conference On Vortex Methods

Author: Kyoji Kamemoto

Publisher: World Scientific

Published: 2000-05-11

Total Pages: 228

ISBN-13: 9814493287

DOWNLOAD EBOOK

Vortex methods have been developed and applied to many kinds of flows related to various problems in wide engineering and scientific fields. The purpose of the First International conference on Vortex methods was to provide an opportunity for engineers and scientists to present their achievements, exchange ideas and discuss new developments in mathematical and physical modeling techniques and engineering applications of vortex methods.


A Discrete Vortex Analysis of Flow About Stationary and Transversely Oscillating Circular Cylinders

A Discrete Vortex Analysis of Flow About Stationary and Transversely Oscillating Circular Cylinders

Author: Turgut Sarpkaya

Publisher:

Published: 1979

Total Pages: 0

ISBN-13:

DOWNLOAD EBOOK

A comprehensive numerical model has been developed to investigate the characteristics of flow about a circular cylinder undergoing synchronized transverse oscillations. The model is based on the rediscretization of the shear layers, wake-boundary-layer interaction, and the dissipation of vorticity. The forces acting on the cylinder, rate of vorticity flux, Strouhal number, cylinder response, oscillations of the stagnation and separation points, longitudinal and transverse spacing of the vortices, and the base pressure have been calculated and shown to be in conformity with those obtained experimentally. The model has been used to predict the characteristics of hydroelastic oscillations of a cylinder in the range of synchronization. The numerical experiments shed considerable light on the interaction between the fluid motion in the wake and the dynamics of the body. An extensive sensitivity analysis has been carried out to determine the stability of all the parameters and hence the stability of the numerical model itself. (Author).


A Discrete Vortex Analysis of Flow About Stationary and Transversely Oscillating Circular Cylinders

A Discrete Vortex Analysis of Flow About Stationary and Transversely Oscillating Circular Cylinders

Author: Ray L. Shoaff

Publisher:

Published: 1978

Total Pages: 167

ISBN-13:

DOWNLOAD EBOOK

A comprehensive numerical model has been developed to investigate the characteristics of flow about a circular cylinder undergoing synchronized transverse oscillations. The model is based on the rediscretization of the shear layers, wake-boundary-layer interaction, and the dissipation of vorticity. The forces acting on the cylinder, rate of vorticity flux, Strouhal number, cylinder response, oscillations of the stagnation and separation points, longitudinal and transverse spacing of the vortices, and the base pressure have been calculated and shown to be in conformity with those obtained experimentally. The model has been used to predict the characteristics of hydroelastic oscillations of a cylinder in the range of synchronization. The numerical experiments shed considerable light on the interaction between the fluid motion in the wake and the dynamics of the body. An extensive sensitivity analysis has been carried out to determine the stability of all the parameters and hence the stability of the numerical model itself. (Author).


Vortex Shedding from Stationary and Vibrating Bluff Bodies in a Shear Flow

Vortex Shedding from Stationary and Vibrating Bluff Bodies in a Shear Flow

Author:

Publisher:

Published: 1980

Total Pages: 0

ISBN-13:

DOWNLOAD EBOOK

If a fluid is in relative motion past a stationary bluff, or unstreamlined, structure and the vortex shedding frequency approaches one of the natural frequencies of the structure, then resonant flow-induced oscillations of the structure can occur when the damping of the system is sufficiently low. These resonant oscillations are accompanied by a 'lock-on' or capture of the vortex shedding frequency by the vibration frequency over a range of flow speeds, and this lock-on effect causes the wake and the structure to oscillate in unison. The periodic lift and the mean drag forces are amplified as a result of the vibrations, and changes in these fluid forces are closely related to the changes that occur in the flow field in the near wake of the body. Many practical ocean and wind engineering situations involve lightly-damped structures that are located in flows of air or water that are nonuniform along the length of the structure. The primary difference between a uniform flow and a shear flow is the presence and added complexity, in a shear flow, of vorticity whose vector is normal to the plane of the flow. When the incident flow approaches the body this vorticity is turned into the flow direction and interacts with the vortices which are shed from the body into the wake.