Computer simulation studies in condensed matter physics form a rapidly developing field making sigificant contributions to important physical problems. The papers in this volume present new physical results and report new simulation techniques and new ways of interpreting simulational data, which cover simulation of both classical and quantum systems. Topics treated include - Multigrid and nonlocal updating methods in Monte Carlo simulations - Simulations of magnetic excitations and phase transitions - Simulations of aggregate formation - Molecular dynamics and Monte Carlo studies of polymers, polymer mixtures, and fluid flow - Quantum path integral and molecular dynamics studies of clusters and adsorbed layers on surfaces - New methods for simulating interacting boson and fermion systems - Simulational studies of electronic structure.
This volume comprises a selection of the best papers presented at the Seventh Interna tional Symposium on Applications of Laser Techniques to Fluid Mechanics held at The Calouste Gulbenkian Foundation in Lisbon, during the period of July 11 to 14,1994. The papers describe Applications to Fluid Mechanics, Applications to Combustion, Instrumentation for Velocity and Size Measurements and Instrumentation for Whole Field Velocity and demonstrate the continuing and healthy interest in the development of understanding of the methodology and implementation in terms of new instru mentation. The prime objective of this Seventh Symposium was to provide a forum for the presen tation of the most advanced research on laser techniques for flow measurements, and communicate significant results to fluid mechanics. The applications oflaser techniques to scientific and engineering fluid flow research was emphasized, but contributions to the theory and practice of laser methods were also considered where they facilitate new improved fluid mechanic research. Attention was placed on laser-Doppler anemometry, particle sizing and other methods for the measurement of velocity and scalar, such as particle image velocimetry and laser induced fluorescence. We would like to take this opportunity to thank those who participated. The assistance provided by the Advisory Committee, by assessing abstracts was highly appreciated.
Low Reynolds number aerodynamics is important to a number of natural and man-made flyers. Birds, bats, and insects have been of interest to biologists for years, and active study in the aerospace engineering community, motivated by interest in micro air vehicles (MAVs), has been increasing rapidly. The primary focus of this book is the aerodynamics associated with fixed and flapping wings. The book consider both biological flyers and MAVs, including a summary of the scaling laws-which relate the aerodynamics and flight characteristics to a flyer's sizing on the basis of simple geometric and dynamics analyses, structural flexibility, laminar-turbulent transition, airfoil shapes, and unsteady flapping wing aerodynamics. The interplay between flapping kinematics and key dimensionless parameters such as the Reynolds number, Strouhal number, and reduced frequency is highlighted. The various unsteady lift enhancement mechanisms are also addressed, including leading-edge vortex, rapid pitch-up and rotational circulation, wake capture, and clap-and-fling.
Particle image velocimetry, or PIV, refers to a class of methods used in experimental fluid mechanics to determine instantaneous fields of the vector velocity by measuring the displacements of numerous fine particles that accurately follow the motion of the fluid. Although the concept of measuring particle displacements is simple in essence, the factors that need to be addressed to design and implement PIV systems that achieve reliable, accurate, and fast measurements and to interpret the results are surprisingly numerous. The aim of this book is to analyze and explain them comprehensively.
This book describes and explains the basis of bio-inspired, leading-edge tubercles based on humpback whale flippers as passive but effective flow control devices, as well as providing a comprehensive practical guide in their applications. It first discusses the morphology of the humpback whale flipper from a biological perspective, before presenting detailed experimental and numerical findings from past investigations by various experts on the benefits of leading-edge tubercles and their engineering implementations. Leading-edge tubercle designs and functions have attracted considerable interest from researchers in terms of understanding their role in the underwater agility of these whales, and to exploit their flow dynamics in the development of new and novel engineering solutions. Extensive research over the past recent years has demonstrated that the maneuverability of these whales is at least in part due to the leading-edge tubercles acting as passive flow control devices to delay stall and increase lift in the post-stall regime. In addition to the inherent benefits in terms of aerodynamics and hydrodynamics, investigations into leading-edge tubercles have also broadened into areas of noise attenuation, stability and industrial applications. This book touches upon these areas, with an emphasis upon the effects of lifting-surface types, flow regimes, tubercle geometries, lifting-surface stability and potential industrial applications, among others. As such, it features contributions from key experts in the fields of biology, physics and engineering who have conducted significant studies into understanding the various aspects of leading-edge tubercles. Given the broad coverage and in-depth analysis, this book will benefit academic researchers, practicing engineers and graduate students interested in tapping into such a unique but highly functional flow control strategy.
This book reports on the latest knowledge concerning critical phenomena arising in fluid-structure interaction due to movement and/or deformation of bodies. The focus of the book is on reporting progress in understanding turbulence and flow control to improve aerodynamic / hydrodynamic performance by reducing drag, increasing lift or thrust and reducing noise under critical conditions that may result in massive separation, strong vortex dynamics, amplification of harmful instabilities (flutter, buffet), and flow -induced vibrations. Theory together with large-scale simulations and experiments have revealed new features of turbulent flow in the boundary layer over bodies and in thin shear layers immediately downstream of separation. New insights into turbulent flow interacting with actively deformable structures, leading to new ways of adapting and controlling the body shape and vibrations to respond to these critical conditions, are investigated. The book covers new features of turbulent flows in boundary layers over wings and in shear layers immediately downstream: studies of natural and artificially generated fluctuations; reduction of noise and drag; and electromechanical conversion topics. Smart actuators as well as how smart designs lead to considerable benefits compared with conventional methods are also extensively discussed. Based on contributions presented at the IUTAM Symposium “Critical Flow Dynamics involving Moving/Deformable Structures with Design applications”, held in June 18-22, 2018, in Santorini, Greece, the book provides readers with extensive information about current theories, methods and challenges in flow and turbulence control, and practical knowledge about how to use this information together with smart and bio-inspired design tools to improve aerodynamic and hydrodynamic design and safety.
Accessible and beautifully illustrated, this book collates global scientific research on the evolution, ecology and behaviour of barn owls and their relatives into a single volume. For researchers in ornithology, animal behaviour, ecology, conservation biology and evolutionary biology, it will also appeal to amateurs interested in barn owls.
The emphasis in this volume is on the structure and functional design of the integument. The book starts with a brief introduction to some basic principles of physics (mechanics) including Newton’s Three Laws of Motion. These principles are subsequently used to interpret the problems animals encounter in motion. It is in only the last 40 or so years that we have begun to understand how important a role the integument plays in the locomotion of many marine vertebrates. This involves the crossed-fiber architecture, which was first discovered in a classic study on nemertean worms. As a design principle we see that the crossed-fiber architecture is ubiquitous in nature. Research on some of the most dynamic marine vertebrates of the oceans – tuna, dolphins and sharks, and the extinct Jurassic ichthyosaurs – shows precisely how the crossed-fiber architecture contributes to high-speed swimming and (in lamnid sharks) may even aid in energy conservation. However, this design principle is not restricted to animals in the marine biota but is also found as far afield as the dinosaurs and, most recently, has been revealed as a major part of the microstructure of the most complex derivative of the integument, the feather. We see that a variety of phylogenetically diverse vertebrates take to the air by using skin flaps to glide from tree to tree or to the ground, and present detailed descriptions of innovations developed in pursuit of improved gliding capabilities in both extinct and modern day gliders. But the vertebrate integument had even greater things in store, namely true or flapping flight. Pterosaurs were the first vertebrates to use the integument as a membrane in true flapping flight and these interesting extinct animals are discussed on the basis of past and cutting-edge research , most intriguingly with respect to the structure of the flight membrane. Bats, the only mammals that fly, also employ integumental flight membranes. Classic research on bat flight is reviewed and supplemented with the latest research, which shows the complexities of the wing beat cycle to be significantly different from that of birds, as revealed by particle image velocimetry. The book’s largest chapter is devoted to birds, given that they make up nearly half of the over 22,000 species of tetrapods. The flight apparatus of birds is unique in nature and is described in great detail, with innovative research highlighting the complexity of the flight structures, bird flight patterns, and behavior in a variety of species. This is complimented by new research on the brains of birds, which shows that they are more complex than previously thought. The feather made bird flight possible, and was itself made possible by β-keratin, contributing to what may be a unique biomechanical microstructure in nature, a topic discussed in some depth. A highly polarized subject concerns the origin of birds and of the feather. Alleged fossilized protofeathers (primal simple feathers) are considered on the basis of histological and taphonomic investigative studies in Chapter 6. Finally, in Chapter 7 we discuss the controversies associated with this field of research. Professor Theagarten Lingham-Soliar works at the Nelson Mandela Metropolitan University, Port Elizabeth and is an Honorary Professor of Life Sciences at the University of KwaZulu-Natal.
