This book is primarily concerned with turbulence in superfluid helium. Quantized vorticity has traditionally generated great interest among physicists, but there are now also important engineering applications such as liquid helium cooling of superconducting magnets. Presently much research is done on the relationship between superfluid turbulence and classical turbulence, as intense turbulence can be generated in liquid helium due to its small kinematic viscosity. There is also a close relationship between superfluid behaviour and quantized vorticity in liquid helium and in atomic Bose--Einstein condensates. Putting special emphasis on the interplay between the different disciplines involved, this readable account of recent research will appeal not only to established researchers but also to newcomers and graduate students wishing to enter the field.

This book deals with the application of spectral methods to problems of uncertainty propagation and quanti?cation in model-based computations. It speci?cally focuses on computational and algorithmic features of these methods which are most useful in dealing with models based on partial differential equations, with special att- tion to models arising in simulations of ?uid ?ows. Implementations are illustrated through applications to elementary problems, as well as more elaborate examples selected from the authors' interests in incompressible vortex-dominated ?ows and compressible ?ows at low Mach numbers. Spectral stochastic methods are probabilistic in nature, and are consequently rooted in the rich mathematical foundation associated with probability and measure spaces. Despite the authors' fascination with this foundation, the discussion only - ludes to those theoretical aspects needed to set the stage for subsequent applications. The book is authored by practitioners, and is primarily intended for researchers or graduate students in computational mathematics, physics, or ?uid dynamics. The book assumes familiarity with elementary methods for the numerical solution of time-dependent, partial differential equations; prior experience with spectral me- ods is naturally helpful though not essential. Full appreciation of elaborate examples in computational ?uid dynamics (CFD) would require familiarity with key, and in some cases delicate, features of the associated numerical methods. Besides these shortcomings, our aim is to treat algorithmic and computational aspects of spectral stochastic methods with details suf?cient to address and reconstruct all but those highly elaborate examples.

This textbook provides a coherent and structured overview of fluid mechanics, a discipline concerned with many natural phenomena and at the very heart of the most diversified industrial applications and human activities. The balance between phenomenological analysis, physical conceptualization and mathematical formulation serve both as a unifying educational marker and as a methodological guide to the three parts of the work. The thermo-mechanical motion equations of a homogeneous single-phase fluid are established, from which flow models (perfect fluid, viscous) and motion classes (isovolume, barotropic, irrotational, etc.) are derived. Incompressible, potential flows and compressible flows, both in an isentropic evolution and shock, of an ideal inviscid fluid are addressed in the second part. The viscous fluid is the subject of the last one, with the creeping motion regime and the laminar, dynamic and thermal boundary layer. Historical perspectives are included whenever they enrich the understanding of modern concepts. Many examples, chosen for their pedagogical relevance, are dealt with in exercises. The book is intended as a teaching tool for undergraduate students, wishing to acquire a first command of fluid mechanics, as well as graduates in advanced courses and engineers in other fields, concerned with completing what is sometimes a scattered body of knowledge.

Thisbookfocusesonthedynamicsoftheoceanbeingin?uencedbytheEarth'sro- tion and density strati?cation. Fluids in motion are a dif?cult subject of study that traditionally requires advanced knowledge of analytical mathematics, in particularly matrix algebra, differential and integral calculus, and complex analysis. Hence, this fascinating ?eld of science, known as geophysical ?uid dynamics, is accessible only to a limited number of students - those who either are naturally geniuses or those who underwent tough years of intense University study. Fluid processes are inherently complex and analytical solutions describing ?uid dynamics exist only in a few instances and only under highly simpli?ed assu- tions. Computer-based numerical models are required to approximate ?uid beh- ior in more realistic situations. Because of its complexity, universities tend to offer subjects in computational modelling of ?uid dynamics only at postgraduate level. This is a pity given that ?uid processes are truly fascinating in nature and given that the oceans play a signi?cant role in shaping life on Earth. The approach I pursue in this book is different from the traditional approach.

This book is an introduction to current research on the N- vortex problem of fluid mechanics. Its goal is to describe the Hamiltonian aspects of vortex dynamics so that graduate students and researchers can use the book as an entry point into the rather large literature on integrable and non-integrable vortex problems within the broader context of dynamical systems. It is as self-contained as possible: the only training required of the reader is a good background in advanced calculus and ordinary and partial differential equations at the level of a typical undergraduate engineering, physics, or applied mathematics major. Exercises of varying difficulty are found at the end of each chapter which often require the reader to fill in details of proofs or complete examples.

This work describes the different operational regimes and the dominant mechanisms of flows in disperse systems.

Flow induced vibration and noise (FIVN) remains a critical research topic. Even after over 50 years of intensive research, accurate and cost-effective FIVN simulation and measurement techniques remain elusive. This book gathers the latest research from some of the most prominent experts in the field. It describes methods for characterizing wall pressure fluctuations, including subsonic and supersonic turbulent boundary layer flows over smooth and rough surfaces using computational methods like Large Eddy Simulation; for inferring wall pressure fluctuations using inverse techniques based on panel vibrations or holographic pressure sensor arrays; for calculating the resulting structural vibrations and radiated sound using traditional finite element methods, as well as advanced methods like Energy Finite Elements; for using scaling approaches to universally collapse flow-excited vibration and noise spectra; and for computing time histories of structural response, including alternating stresses. This book presents the proceedings of the First International Workshop on Flow Induced Noise and Vibration (FLINOVIA), which was held in Rome, Italy, in November 2013. The authors' backgrounds represent a mix of academia, government, and industry, and several papers include applications to important problems for underwater vehicles, aerospace structures and commercial transportation. The book offers a valuable reference guide for all those working in the area of flow-induced vibration and noise.

A few years ago the Helmholtz Association (HGF) consisting of 15 research Institutions including the German Aerospace Center (DLR) started a network research program called 'Virtual Institutes'. The basic idea of this program was to establish research groups formed by Helmholtz research centers and universities to study and develop methods or technologies for future applications and educate young scientists. It should also enable and encourage the partners of this Virtual Institute after 3 years funding to continue their cooperation in other programs. Following this HGF request and chance the DLR Windtunnel Department of the Institute of Aerodynamics and Flow Technology took the initiative and established a network with other DLR institutes and German u- versities RWTH Aachen, University of Stuttgart and Technical University Munich. The main goal of this network was to share the experience in system analysis, ae- dynamics and material science for aerospace for improving the understanding and applicability of some key technologies for future reusable space transportation s- tems. Therefore, the virtual institute was named RESPACE (Key Technologies for Re- Usable Space Systems).

Many leading experts contribute to this follow-up to An Introduction to Reservoir Simulation using MATLAB/GNU Octave: User Guide for the MATLAB Reservoir Simulation Toolbox (MRST). It introduces more advanced functionality that has been recently added to the open-source MRST software. It is however a self-contained introduction to a variety of modern numerical methods for simulating multiphase flow in porous media, with applications to geothermal energy, chemical enhanced oil recovery (EOR), flow in fractured and unconventional reservoirs, and in the unsaturated zone. The reader will learn how to implement new models and algorithms in a robust, efficient manner. A large number of numerical examples are included, all fully equipped with code and data so that the reader can reproduce the results and use them as a starting point for their own work. Like the original textbook, this book will prove invaluable for researchers, professionals and advanced students using reservoir simulation methods. This title is available as Open Access on Cambridge Core.

The scope of this book is to present in a systematic and unified manner the ray method (in its various forms) for studying nonlinear wave propagation in situations of physical interest (essentially fluid dynamics and plasma physics). The book could be used for an advanced graduate course on nonlinear waves. It should also be of interest to applied mathematicians, physicists and engineers, working in areas related to nonlinear waves.

In these lectures, most of them given at the University of Montreal while he held the Aisenstadt Chair, Roman Jackiw provides a view of fluid dynamics from an entirely novel perspective. He begins by explaining the motivation and reviewing the classical theory, but in a manner different from textbook discussions. Among other topics, he discusses conservation laws and Euler equations, and a method for finding their canonical structure; C. Eckart's Lagrangian and a relativistic generalization for vortex-free motion; nonvanishing vorticity and the Clebsch parameterization for the velocity vector. Jackiw then discusses some specific models for nonrelativistic and relativistic fluid mechanics with more than one spatial dimension, including the Chaplygin gas (whose negative pressure is inversely proportional to density), and the scalar Born-Infeld model. He shows how both the Chaplygin gas and the Born-Infeld model devolve from the parameterization-invariant Nambu-Goto action. As in particle physics, Jackiw shows, fluid mechanics enhanced by supersymmetry, non-Abelian degrees of freedon, and non commuting coordinates. Jackiw discusses the need for a non-Abelian fluid mechanics, and proposes a Lagrangian, which involves a non-Abelian auxiliary field, whose Chern-Simons density should be a total derivative. The generalization to magnetohydrodynamics, which results from including a dynamical non-Abelian guage filed, reduces in the Abelian limit to conventional magnetohydrodynamics. For one-dimensional cases, the models mentioned above are completely integrable, and Jackiw gives the general solution of the Chaplygin gas and the Born-Infeld model on a line, as well as a general solution of the Nambu-Goto theory for a 1-brane (string) in two spatial dimensions. Jackiw discusses the need for a non-Abelian fluid mechanics and proposes a Lagrangian, which involves a non-Abelian auxiliary field whose Chern-Simons density should be a total derivative. The generalization to magnetohydrodynamics, which results from including a dynamical non-Abelian gauge field, reduces in the Abelian limit to conventional magnetohydrodynamics.

This book gives the basic analytical framework for the description of turbulent flows and discusses various types encountered by civil engineers involved in hydraulic analysis and design, as well as environmental engineers. It also presents a detailed exposition of the various dimensions of turbulent flow. The book is extremely useful for practising engineers, particularly in the field of hydraulic analysis and design, building dynamics and environmental engineering.

Turbulence and the associated turbulent transport of scalar and vector fields is a classical physics problem that has dazzled scientists for over a century, yet many fundamental questions remain. Igor Rogachevskii, in this concise book, systematically applies various analytical methods to the turbulent transfer of temperature, particles and magnetic field. Introducing key concepts in turbulent transport including essential physics principles and statistical tools, this interdisciplinary book is suitable for a range of readers such as theoretical physicists, astrophysicists, geophysicists, plasma physicists, and researchers in fluid mechanics and related topics in engineering. With an overview to various analytical methods such as mean-field approach, dimensional analysis, multi-scale approach, quasi-linear approach, spectral tau approach, path-integral approach and analysis based on budget equations, it is also an accessible reference tool for advanced graduates, PhD students and researchers.

This book is the result of two decades of research work which started with an accidental observation. One of my students, Dipl. phys. Volkmar Lenz, - ticed that the speckle pattern of laser light scattered by a cuvette containing diluted milk performed a strange motion every time he came near the cuvette with his thumb. After thinkingabout this e?ect we came to the conclusion that this motion can only be caused by scatteringparticles with di?erent velocities, as in the case of the di?raction pattern of an optical grating: A linear motion of the grating does not change the pattern whereas a rotation of the grating does. The observed speckle motion could then be explained qualitatively as produced by the inhomogeneous velocity of the convection within the cuvette which was produced by the heat of the thumb. The theoretical treatment of this e?ect revealed that the velocity gradient of the light scattering medium is responsible for the speckle motion. The idea to use this e?ect for developingmeasurement techniques for velocity gradients arose almost immediately. For that purpose we had to develop not only experimental set-ups to measure the pattern velocity but also the theory which describes the connection between this velocity and the velocity gradient. The result of this work together with the description of a method developed by another group forms the contents of this book. I am indebted to the students who worked in my laboratory and developed the measurement techniques. These were, in temporal order, Dr.

Vortex flow is one of the fundamental types of fluid and gas motion. These flows are the most spectacular in the form of concentrated vortices, characterized by the localization of vorticity (curl of velocity) in bounded regions of a space, beyond which the vorticity is either absent or rapidly falls down to zero. Concentrated vortices are often observed in nature, exemplified by atmospheric cyclones, whirlwinds and tornados, oceanic vortices, whirlpools on a water s- face, and ring vortices caused by explosive outburst of volcanoes. In technical - vices concentrated vortices form when flow separates from sharp edges of flying vehicles and ships. Among these are vortices flowing off the ends of airplane wings, and intentionally generated vortices for intensification of burning in c- bustion chambers, vortices in cyclonic devices used for mixing or separation of impurities in fluids and gases. One such remarkable and frequent type of conc- trated vortices is a vortex ring which constitutes a vortex tube closed into a t- oidal ring moving in a surrounding fluid like an isolated body out of contact with solid boundaries of the flow region if such boundaries exist. Formation and motion of vortex rings are important part of the dynamics of a continuum medium and have been studied for more than a century.

Condensing 40 years of teaching experience, this unique textbook will provide students with an unrivalled understanding of the fundamentals of fluid mechanics, and enable them to place that understanding firmly within a biological context. Each chapter introduces, explains, and expands a core concept in biofluid mechanics, establishing a firm theoretical framework for students to build upon in further study. Practical biofluid applications, clinical correlations, and worked examples throughout the book provide real-world scenarios to help students quickly master key theoretical topics. Examples are drawn from biology, medicine, and biotechnology with applications to normal function, disease, and devices, accompanied by over 500 figures to reinforce student understanding. Featuring over 120 multicomponent end-of-chapter problems, flexible teaching pathways to enable tailor-made course structures, and extensive Matlab and Maple code examples, this is the definitive textbook for advanced undergraduate and graduate students studying a biologically-grounded course in fluid mechanics.

The main idea of the present study is to demonstrate that the qualitative theory of diffe rential equations, when applied to problems in fluid-and gasdynamics, will contribute to the understanding of qualitative aspects of fluid flows, in particular those concerned with geometrical properties of flow fields such as shape and stability of its streamline patterns. It is obvious that insight into the qualitative structure of flow fields is of great importance and appears as an ultimate aim of flow research. Qualitative insight fashions our know ledge and serves as a good guide for further quantitative investigations. Moreover, quali tative information can become very useful, especially when it is applied in close corres pondence with numerical methods, in order to interpret and value numerical results. A qualitative analysis may be crucial for the investigation of the flow in the neighbourhood of singularities where a numerical method is not reliable anymore due to discretisation er rors being unacceptable. Up till now, familiar research methods -frequently based on rigorous analyses, careful nu merical procedures and sophisticated experimental techniques -have increased considera bly our qualitative knowledge of flows, albeit that the information is often obtained indirectly by a process of a careful but cumbersome examination of quantitative data. In the past decade, new methods are under development that yield the qualitative infor mation more directly. These methods, make use of the knowledge available in the qualitative theory of differen tial equations and in the theory of bifurcations."

This textbook presents a systematic study of the qualitative and geometric theory of nonlinear differential equations and dynamical systems. Although the main topic of the book is the local and global behavior of nonlinear systems and their bifurcations, a thorough treatment of linear systems is given at the beginning of the text. All the material necessary for a clear understanding of the qualitative behavior of dynamical systems is contained in this textbook, including an outline of the proof and examples illustrating the proof of the Hartman-Grobman theorem, the use of the Poincare map in the theory of limit cycles, the theory of rotated vector fields and its use in the study of limit cycles and homoclinic loops, and a description of the behavior and termination of one-parameter families of limit cycles. In addition to minor corrections and updates throughout, this new edition includes materials on higher order Melnikov theory and the bifurcation of limit cycles for planar systems of differential equations, including new sections on Francoise's algorithm for higher order Melnikov functions and on the finite codimension bifurcations that occur in the class of bounded quadratic systems.

foundations of duct acoustics to the acoustic design of duct systems, through practical modeling, optimization and measurement techniques. Discover in-depth analyses of one- and three-dimensional models of sound generation, propagation and radiation, as techniques for assembling acoustic models of duct systems from simpler components are described. Identify the weaknesses of mathematical models in use and improve them by measurement when needed. Cope with challenges in acoustic design, and improve understanding of the underlying physics, by using the tools described. An essential reference for engineers and researchers who work on the acoustics of fluid machinery ductworks.

This technical book considers the application side of LDA techniques. Starting from the basic theories that are crucial for each LDA user, the main subject of the book is focused on diverse application methods. In details, it deals with universal methodical techniques that have been mostly developed in the last 15 years. The book thus gives for the first time an application reference for LDA users in improving the optical conditions and enhancing the measurement accuracies. It also provides the guidelines for simplifying the measurements and correcting measurement errors as well as for clarifying the application limits and extending the application areas of LDA techniques. Beside the treatments of some traditional optical and flow mechanical features influencing the measurement accuracies, the book shows a broad spectrum of LDA application methods in the manner of measuring the flow turbulence, resolving the secondary flow structures, and quantifying the optical aberrations at measurements of internal flows etc.. Thus, it also supports the further developments of both the hard- and software of LDA instrumentations.

Dynamics of Ice Sheets and Glaciers presents an introduction to the dynamics and thermodynamics of flowing ice masses on Earth. Based on an outline of general continuum mechanics, the different initial-boundary-value problems for the flow of ice sheets, ice shelves, ice caps and glaciers are systematically derived. Special emphasis is put on developing hierarchies of approximations for the different systems, and suitable numerical solution techniques are discussed. A separate chapter is devoted to glacial isostasy. The book is appropriate for graduate courses in glaciology, cryospheric sciences, environmental sciences, geophysics and related fields. Standard undergraduate knowledge of mathematics (calculus, linear algebra) and physics (classical mechanics, thermodynamics) provide a sufficient background for successfully studying the text.

Crystal growth, casting, soldering, welding, high-energy surface treatment, nuclear safety systems and geophysical flows are just a few examples where solidification and convection occur together. These processes are interactive on micro- and macroscales: flow affects the distribution of heat and species and hence the freezing process, while solidification evolves flow boundaries, as in crusting, for example, and hence can radically alter the convection. Mathematical modellers, experimentalists and applied scientists were invited to this colloquium with the aim of consolidating our understanding of such interactions, of identifying key outstanding issues, and of developing new approaches in this important area of fundamental research. Both invited and contributed papers focus on both fundamental and technologically relevant problems.

This book grew out of lectures on geophysical fluid dynamics delivered over many years at the Moscow Institute of Physics and Technology by the author (and, with regard to some parts of the book, by his colleagues). During these lectures the students were advised to read many books, and sometimes individual articles, in order to acquaint themselves with the necessary material, since there was no single book available which provided a sufficiently complete and systematic account (except, perhaps, the volumes on Hydrophysics of the Ocean, Hydrodynamics of the Ocean, and Geodynamics in the ten-volume Oceanology series published by Nauka Press in 1978-1979; these refer, however, specifically to the ocean, and anyway they are much too massive to be convenient for study by students). As far as we know, no text corresponding to our understanding of geophysical fluid dynamics has as yet been published outside the Soviet Union. The present book is designed to fill this gap. Since it is customary to write the preface after the entire book has been completed, the author has an opportunity there to raise some points of possible criticism by the reviewers and readers. First of all, note that this work presents the theoretical fundamentals of geophysical fluid dynamics, and that observational and experimental data (which in the natural sciences are always very copious) are referred to only rarely and briefly.

This book addresses the hydrostatics and stability of ships and other floating marine structures - a fundamental aspect of naval architecture and offshore engineering for naval architects and marine engineers. It starts from the most basic concepts, assuming that the reader has no prior knowledge of the subject. By presenting the topic in a methodical and step-by-step manner, the book helps students to enhance their understanding, while also providing valuable guidelines for lecturers teaching related courses.