This book presents the latest research results in the area of applied nonlinear dynamics and chaos theory. Papers by three academic generations address new applications of nonlinear dynamics to mechanics, including fluid-structure interaction, machining and mechanics of solids, and many other applications.
The interest of the applied mechanics community in chaotic dynamics of engineering systems has exploded in the last fifteen years, although research activity on nonlinear dynamical problems in mechanics started well before the end of the Eighties. It developed first within the general context of the classical theory of nonlinear oscillations, or nonlinear vibrations, and of the relevant engineering applications. This was an extremely fertile field in terms of formulation of mechanical and mathematical models, of development of powerful analytical techniques, and of understanding of a number of basic nonlinear phenomena. At about the same time, meaningful theoretical results highlighting new solution methods and new or complex phenomena in the dynamics of deterministic systems were obtained within dynamical systems theory by means of sophisticated geometrical and computational techniques. In recent years, careful experimental studies have been made to establish the actual occurrence and observability of the predicted dynamic phenomena, as it is vitally needed in all engineering fields. Complex dynamics have been shown to characterize the behaviour of a great number of nonlinear mechanical systems, ranging from aerospace engineering applications to naval applications, mechanical engineering, structural engineering, robotics and biomechanics, and other areas. The International Union of Theoretical and Applied Mechanics grasped the importance of such complex phenomena in the Eighties, when the first IUTAM Symposium devoted to the general topic of nonlinear and chaotic dynamics in applied mechanics and engineering was held in Stuttgart (1989).
This volume contains the proceedings of the IUTAM Symposium on Elastohydrodynamics and Microelastohydrodynamics held in Cardiff from 1-3 September 2004. It contains 31 articles by leading researchers in the field. The symposium focused on theoretical, experimental and computational issues in elastohydrodynamic lubrication (EHL) both in relation to smooth surfaces and in situations where the film is of the same order or thinner than the surface roughness (micro-EHL). The last IUTAM Symposium in this general area of contact of deformable bodies was in 1974. The emphasis in the Symposium was upon fundamental issues such as: solution methods; lubricant rheological models, thermal effects; both low and high elastic modulus situations; human and replacement joints; fluid traction; dynamic effects, asperity lubrication and the failure of lubrication; surface fatigue and thermal distress under EHL conditions. The book will be useful to those active in basic elastohydrodynamics research who wish to gain an up-to-date understanding of the subject from leading experts in the field.
The IUTAM Symposium on Mechanical and Electromagnetic Waves in Structured Media took place at the University of Sydney from January 18- 22, 1999. It brought together leading researchers from eleven countries for a week-long meeting, with the aim of providing cross-links between the com- nities studying related problems involving elastic and electromagnetic waves in structured materials. After the meeting, participants were invited to submit articles based on their presentations, which were refereed and assembled to constitute these Proceedings. The topics covered here represent areas at the forefront of research intoelastic and electromagnetic waves. They include effect of nonlinearity, diffusion and multiple scattering on waves, as well as asymptotic and numerical techniques. Composite materials are discussed in depth, with example systems ranging fromdusty plasmas to a magneto-elastic microstructured system. Also included are studies of homogenisation, that field which seeks to determine equivalent homogeneous systems which can give equivalent wave properties to structured materials, and inverse problems, in which waves are used as a probe to infer structural details concerning scattering systems. There are also strong groups of papers on the localization of waves by random systems, and photonic and phononic band gap materials. These are being developed by analogue with semiconductors for electrons, and hold out the promise of enabling designers to control the propagation of waves through materials in novel ways. We would like to thank the other members of the Scientific Committee (A.
During the last decades, continuum mechanics of porous materials has achieved great attention, since it allows for the consideration of the volumetrically coupled behaviour of the solid matrix deformation and the pore-fluid flow. Naturally, applications of porous media models range from civil and environmental engineering, where, e. g. , geote- nical problems like the consolidation problem are of great interest, via mechanical engineering, where, e. g. , the description of sinter materials or polymeric and metallic foams is a typical problem, to chemical and biomechanical engineering, where, e. g. , the complex structure of l- ing tissues is studied. Although these applications are principally very different, they basically fall into the category of multiphase materials, which can be described, on the macroscale, within the framework of the well-founded Theory of Porous Media (TPM). With the increasing power of computer hardware together with the rapidly decreasing computational costs, numerical solutions of complex coupled problems became possible and have been seriously investigated. However, since the quality of the numerical solutions strongly depends on the quality of the underlying physical model together with the experimental and mathematical possibilities to successfully determine realistic material parameters, a successful treatment of porous materials requires a joint consideration of continuum mechanics, experimental mechanics and numerical methods. In addition, micromechanical - vestigations and homogenization techniques are very helpful to increase the phenomenological understanding of such media.
In the last decades, new experimental and numerical techniques have taken many advanced features of porous media mechanics down to practical engineering applications. This happened in areas that sometimes were not even suspected to be open to engineering ideas at all. The challenge that often faces engineers in the field of geomechanics, biomechanics, rheology and materials science is the translation of ideas existing in one field to solutions in the other. The purpose of the IUTAM symposium from which this proceedings volume has been compiled was to dive deep into the mechanics of those porous media that involve mechanics and chemistry, mechanics and electromagnetism, mechanics and thermal fluctuations of mechanics and biology. The different sections have purposely not been formed according to field interest, but on the basis of the physics involved.
Phase transition phenomena in solids are of vital interest to physicists, materials scientists, and engineers who need to understand and model the mechanical behavior of solids during various kinds of phase transformations. This volume is a collection of 29 written contributions by distinguished invited speakers from 14 countries to the IUTAM Symposium on Mechanics of Martensitic Phase Transformation in Solids, the first IUTAM Symposium focusing on this topic. It contains basic theoretical and experimental aspects of the recent advances in the mechanics research of martensitic phase transformations. The main topics include microstructure and interfaces, material instability and its propagation, micromechanics approaches, interaction between plasticity and phase transformation, phase transformation in thin films, single and polycrystalline shape memory alloys, shape memory polymers, TRIP steels, etc. Due to the multidisciplinary nature of the research covered, this volume will be of interest to researchers, graduate students and engineers in the field of theoretical and applied mechanics as well as materials science and technology.
This book is concerned with the methods of solving the nonlinear Boltz mann equation and of investigating its possibilities for describing some aerodynamic and physical problems. This monograph is a sequel to the book 'Numerical direct solutions of the kinetic Boltzmann equation' (in Russian) which was written with F. G. Tcheremissine and published by the Computing Center of the Russian Academy of Sciences some years ago. The main purposes of these two books are almost similar, namely, the study of nonequilibrium gas flows on the basis of direct integration of the kinetic equations. Nevertheless, there are some new aspects in the way this topic is treated in the present monograph. In particular, attention is paid to the advantages of the Boltzmann equation as a tool for considering nonequi librium, nonlinear processes. New fields of application of the Boltzmann equation are also described. Solutions of some problems are obtained with higher accuracy. Numerical procedures, such as parallel computing, are in vestigated for the first time. The structure and the contents of the present book have some com mon features with the monograph mentioned above, although there are new issues concerning the mathematical apparatus developed so that the Boltzmann equation can be applied for new physical problems. Because of this some chapters have been rewritten and checked again and some new chapters have been added.
