Fluid Mechanics At Interfaces 1

Interfaces are present in most fluid mechanics problems. They not only denote phase separations and boundary conditions, but also thin flames and discontinuity waves. Fluid Mechanics at Interfaces 1 focuses on the science of interfaces, in particular, using various scientific methods of analysis relating to space, speed and time. Our investigation takes us from the microscopic or small scale (starting with molecular and nanoscopic scales) to the macroscopic (including meso and interstellar scales), and also explores the laws of interfaces (classical mechanics, quantum mechanics and relativistic mechanics). Chapter 1 examines the questions raised by modeling interfaces in the presence of one or more fluid phases. Chapter 2 discusses the action of turbulence in liquid–vapor flows that contain both small, dispersed bubbles as well as large bubbles, with heat exchanges at the interfaces. In addition, a new model is presented, using large eddy simulation (LES). Chapter 3 studies an original method for calculating the drag force and thermal transfers in flows around networks of spherical particles, while Chapter 4 focuses on the relationships between interfaces and critical fluids. Chapter 5 examines shearing, which causes anomalies in the Brownian motion of particles in strongly fluctuating near-critical mixtures, and Chapter 6 introduces basic concepts related to combustion interfaces, raising the question of the combustion of solids, before ending with a brief presentation of the Rankine–Hugoniot theory and a historical overview of the research carried out in the field of combustion.

In this book experts discuss research and applications in interfacial fluid dynamics.

This book highlights some recent advances in interfacial research in the fields of fluid mechanics and materials science at the beginning of the twenty-first century. It is an extension of the presentations made during the conference “Interfaces for the 21st Century,” held on August 16-18, 1999, in Monterey, California. It includes papers by sixteen renowned experts in the field of interfacial mechanics, abstracts contributed by research scientists, and a summary of a panel discussion on future research directions. The book covers experimental and theoretical approaches, with the unifying philosophy being the investigation of new techniques for modeling the dynamics of interfaces. A number of new and exciting solution methods and experimental studies, as well as the physical problems that initiated them, are presented.

Interfaces are present in most fluid mechanics problems. They not only denote phase separations and boundary conditions, but also thin flames and discontinuity waves. Fluid Mechanics at Interfaces 1 focuses on the science of interfaces, in particular, using various scientific methods of analysis relating to space, speed and time. Our investigation takes us from the microscopic or small scale (starting with molecular and nanoscopic scales) to the macroscopic (including meso and interstellar scales), and also explores the laws of interfaces (classical mechanics, quantum mechanics and relativistic mechanics). Chapter 1 examines the questions raised by modeling interfaces in the presence of one or more fluid phases. Chapter 2 discusses the action of turbulence in liquid–vapor flows that contain both small, dispersed bubbles as well as large bubbles, with heat exchanges at the interfaces. In addition, a new model is presented, using large eddy simulation (LES). Chapter 3 studies an original method for calculating the drag force and thermal transfers in flows around networks of spherical particles, while Chapter 4 focuses on the relationships between interfaces and critical fluids. Chapter 5 examines shearing, which causes anomalies in the Brownian motion of particles in strongly fluctuating near-critical mixtures, and Chapter 6 introduces basic concepts related to combustion interfaces, raising the question of the combustion of solids, before ending with a brief presentation of the Rankine–Hugoniot theory and a historical overview of the research carried out in the field of combustion.

Environmental Fluid Mechanics (EFM) studies the motion of air and water at several different scales, the fate and transport of species carried along by these fluids, and the interactions among those flows and geological, biological, and engineered systems. EFM emerged some decades ago as a response to the need for tools to study problems of flow and transport in rivers, estuaries, lakes, groundwater and the atmosphere; it is a topic of increasing importance for decision makers, engineers, and researchers alike. The second edition of the successful textbook "Fluid Mechanics of Environmental Interfaces" is still aimed at providing a comprehensive overview of fluid mechanical processes occurring at the different interfaces existing in the realm of EFM, such as the air-water interface, the air-land interface, the water-sediment interface, the surface water-groundwater interface, the water-vegetation interface, and the water-biological systems interface. Across any of these interfaces mass, momentum, and heat are exchanged through different fluid mechanical processes over various spatial and temporal scales. In this second edition, the unique feature of this book, considering all the topics from the point of view of the concept of environmental interface, was maintained while the chapters were updated and five new chapters have been added to significantly enlarge the coverage of the subject area. The book starts with a chapter introducing the concept of EFM and its scope, scales, processes and systems. Then, the book is structured in three parts with fifteen chapters. Part one, which is composed of four chapters, covers the processes occurring at the interfaces between the atmosphere and the surface of the land and the seas, including the transport of dust and the dispersion of passive substances within the atmosphere. Part two deals in five chapters with the fluid mechanics at the air-water interface at small scales and sediment-water interface, including the advective diffusion of air bubbles, the hyporheic exchange and the tidal bores. Finally, part three discusses in six chapters the processes at the interfaces between fluids and biotic systems, such as transport processes in the soil-vegetation-lower atmosphere system, turbulence and wind above and within the forest canopy, flow and mass transport in vegetated open channels, transport processes to and from benthic plants and animals and coupling between interacting environmental interfaces. Each chapter has an educational part, which is structured in four sections: a synopsis of the chapter, a list of keywords that the reader should have encountered in the chapter, a list of questions and a list of unsolved problems related to the topics covered by the chapter. The book will be of interest to graduate students and researchers in environmental sciences, civil engineering and environmental engineering, (geo)physics, atmospheric science, meteorology, limnology, oceanography, and applied mathematics.

Interfaces are present in most fluid mechanics problems. They not only denote phase separations and boundary conditions, but also thin flames and discontinuity waves. Fluid Mechanics at Interfaces 2 examines cases that involve one-dimensional or bi-dimensional manifolds, not only in gaseous and liquid physical states but also in subcritical fluids and in single- and multi-phase systems that may be pure or mixed. Chapter 1 addresses certain aspects of turbulence in discrete mechanics, briefly describing the physical model associated with discrete primal and dual geometric topologies before focusing on channel flow simulations at turbulence-inducing Reynolds numbers. Chapter 2 centers on atomization in an accelerating domain. In one case, an initial Kelvin–Helmholtz instability generates an acceleration field, in turn creating a Rayleigh–Taylor instability which ultimately determines the size of the droplets formed. Chapter 3 explores numerical studies of pipes with sudden contraction using OpenFOAM, and focuses on modeling that will be useful for engines and automobiles. Chapters 4 and 5 study the evaporation of droplets that are subject to high-frequency perturbations, a possible cause of instabilities in injection engines. The Heidmann model, which replaces the droplets in motion in a combustion chamber with a single continuously-fed droplet, is made more complex by considering the finite conduction heat transfer phenomenon. Finally, Chapter 6 is devoted to a study of the rotor blade surface of a Savonius wind turbine, considering both a non-stationary and a three-dimensional flow.

This book constitutes a comprehensive survey of the balance equations for mass, momentum and energy for the interfaces in pure fluids and mixtures. Constitutive laws are presented for many situations in engineering science, and examples are provided, including surface viscosity effects, variable surface tension and vapor recoil. In addition, some extensions of existing theory are given: stretch effect in premixed flames, relaxation zones downstream two-phase shock waves, and effective surface tension for high gradient zones.

This book highlights some recent advances in interfacial research in the fields of fluid mechanics and materials science at the beginning of the twenty-first century. It is an extension of the presentations made during the conference "Interfaces for the 21st Century," held on August 16?18, 1999, in Monterey, California. It includes papers by sixteen renowned experts in the field of interfacial mechanics, abstracts contributed by research scientists, and a summary of a panel discussion on future research directions. The book covers experimental and theoretical approaches, with the unifying philosophy being the investigation of new techniques for modeling the dynamics of interfaces. A number of new and exciting solution methods and experimental studies, as well as the physical problems that initiated them, are presented.