Author: Berk Geveci Publisher: ISBN: Category : Plates, Aluminum Languages : en Pages : 564
Book Description
The response of two- and three-dimensional plates to the motion of a single recti-linear vortex in incompressible flow is studied for various physical parameters. It is shown that the passage of a vortex over the plate can induce complex vibrations and large deformations of the plate.
Author: Michele Ducceschi Publisher: ISBN: Category : Languages : en Pages : 154
Book Description
Thin plate vibrations display a rich and complex dynamics that ranges from linear to strongly nonlinear regimes when increasing the vibration amplitude with respect to the thickness. This thesis is concerned with the development of a numerical code able to simulate without restrictions this large spectrum of dynamical features, described by the von Kármán equations, in the case of flat, homogeneous plates presenting a rectangular geometry. The main application of such a code is to produce gong-like sounds, in the context of sound synthesis by physical modelling. For that, a modal approach is used, in order to reduce the original Partial Differential Equations to a set of couped Ordinary Differential Equations. An energy-conserving, second-order accurate time integration scheme is developed in order to yield a stability condition. The most appealing features of the modal scheme are its accuracy and the possibility of implementing a rich loss mechanism by selecting an appropriate damping factor for each one of the modes. The sound produced by the numerical code is systematically compared to another numerical technique based on Finite Difference techniques. Fundamental aspects of the physics of nonlinear vibrations are also considered in the course of this work. When a plate vibrates in a weakly nonlinear regime, modal couplings produce amplitude-dependent vibrations, internal resonances, instabilities, jumps and bifurcations. The modal scheme is used to construct and analyse the nonlinear response of the plate in the vicinity of its first eigenfrequencies, both in free and forced-damped vibrations, showing as a result the effect of damping and forcing on the nonlinear normal modes of the underlying Hamiltonian system. When plates vibrate in a strongly nonlinear regime, the most appropriate description of the dynamics is given in terms of the statistical properties of the system, because of the vast number of interacting degrees-of-freedom. Theoretically, this framework is offered by the Wave Turbulence theory. Given the large amount of modes activated in such vibrations, a Finite Difference, energy-conserving code is preferred over the modal scheme. Such a scheme allows to produce a cascade of energy including thousands of modes when the plate is forced sinusoidally around one of its lowest eigenfrequencies. A statistical interpretation of the outcome of the simulation is offered, along with a comparison with experimental data and other numerical results found in the literature. In particular, the effect of the pointwise forcing as well as geometrical imperfections of the plates are analysed.
Author: Sanjay Singh Publisher: Springer ISBN: 9811058490 Category : Technology & Engineering Languages : en Pages : 369
Book Description
This book includes high-quality research papers presenting the latest advances in aerospace and related engineering fields. The papers are organized according to six broad areas (i) Aerospace Propulsion, (ii) Space Research, Avionics and Instrumentation, (iii) Aerodynamics Wind Tunnel and Computational fluid dynamics (CFD), (iv) Structural Analysis and Finite Element Method (FEM), (v) Materials, Manufacturing and Air Safety and (vi) Aircraft Environmental and Control System and Stability, making it easy for readers to find the information they require. Offering insights into the state of the art in aerospace engineering, the original research presented is valuable to academics, researchers, undergraduate and postgraduate students as well as professionals in industry and R&D. The clearly written book can be used for the validation of data, and the development of experimental and simulation techniques as well as other mathematical approaches.
Author: Tomomichi Nakamura Publisher: Butterworth-Heinemann ISBN: 0080983529 Category : Technology & Engineering Languages : en Pages : 425
Book Description
In many plants, vibration and noise problems occur due to fluid flow, which can greatly disrupt smooth plant operations. These flow-related phenomena are called flow-induced vibration. This book explains how and why such vibrations happen and provides hints and tips on how to avoid them in future plant design. The world-leading author team doesn't assume prior knowledge of mathematical methods and provides the reader with information on the basics of modeling. The book includes several practical examples and thorough explanations of the structure, the evaluation method and the mechanisms to aid understanding of flow-induced vibrations. - Helps ensure smooth plant operations - Explains the structure, evaluation method and mechanisms - Shows how to avoid vibrations in future plant design
Author: Marco Amabili Publisher: Cambridge University Press ISBN: 1139469029 Category : Science Languages : en Pages : 391
Book Description
This unique book explores both theoretical and experimental aspects of nonlinear vibrations and stability of shells and plates. It is ideal for researchers, professionals, students, and instructors. Expert researchers will find the most recent progresses in nonlinear vibrations and stability of shells and plates, including advanced problems of shells with fluid-structure interaction. Professionals will find many practical concepts, diagrams, and numerical results, useful for the design of shells and plates made of traditional and advanced materials. They will be able to understand complex phenomena such as dynamic instability, bifurcations, and chaos, without needing an extensive mathematical background. Graduate students will find (i) a complete text on nonlinear mechanics of shells and plates, collecting almost all the available theories in a simple form, (ii) an introduction to nonlinear dynamics, and (iii) the state of art on the nonlinear vibrations and stability of shells and plates, including fluid-structure interaction problems.
Author: Michael P. Païdoussis Publisher: Cambridge University Press ISBN: 9781107652958 Category : Technology & Engineering Languages : en Pages : 414
Book Description
Structures in contact with fluid flow, whether natural or man-made, are inevitably subject to flow-induced forces and flow-induced vibration: from plant leaves to traffic signs and to more substantial structures, such as bridge decks and heat exchanger tubes. Under certain conditions the vibration may be self-excited, and it is usually referred to as an instability. These instabilities and, more specifically, the conditions under which they arise are of great importance to designers and operators of the systems concerned because of the significant potential to cause damage in the short term. Such flow-induced instabilities are the subject of this book. In particular, the flow-induced instabilities treated in this book are associated with cross-flow, that is, flow normal to the long axis of the structure. The book treats a specific set of problems that are fundamentally and technologically important: galloping, vortex-shedding oscillations under lock-in conditions, and rain-and-wind-induced vibrations, among others. The emphasis throughout is on providing a physical description of the phenomena that is as clear and up-to-date as possible.
Author: Berk Geveci
Author: Michele Ducceschi
Author: 
Author: Sanjay Singh
Author: 
Author: Professor of Mechanics Peter Hagedorn
Author: Tomomichi Nakamura
Author: Marco Amabili
Author: Michael P. Païdoussis
Author: C. Y. Chia