This book presents a comprehensive survey of the origin of turbulence in near-wall shear layer flows. Instead of going too far into details modern approaches to the problem are discussed in a conceptual treatment. The transition from laminar to turbulent flows in shear layers is described including the generation of flow perturbations, their amplification and development, the breakdown of the initial laminar state, and transformation to a turbulent regime. This book also presents new approaches to boundary-layer transitions with strong external-flow perturbations and to the prediction and control of the presented near-wall transitions to turbulence. This book is addressed to researchers, lecturers and students in engineering, physics and mathematics.

This book is aimed at scientists and practicing engineers who are currently exploring or would like to explore the complexity of fabrication processes of polymer composites. It deals with the mechanics and modeling aspects of discontinuous and continuous fiber composites and familarizes the engineer with the critical and fundamental issues of material processing and transport phenomena in polymeric composites and their applications in modeling and simulating specific composite manufacturing processes.

Divided into three parts, Part A deals with the deformation science or rheology of these filled materials. It clearly shows the need to characterize their flow behavior before one can draw any conclusions about its processibility during manufacturing. Part B focuses on development of constitutive equations to describe the flow and deformation behavior of such materials under external processing conditions. Part C discusses the mathematical models for selected composite processes and their implementation into a computer simulation to analyze the process behavior. The processes represented in Part C cover a cross-section of important manufacturing processes and maintain a balance between processes that use short fibers and continuous fibrous materials.

This book gathers the proceedings of the 12th instalment in the bi-annual Workshop series on Direct and Large Eddy Simulation (DLES), which began in 1994 and focuses on modern techniques used to simulate turbulent flows based on the partial or full resolution of the instantaneous turbulent flow structure. With the rapidly expanding capacities of modern computers, this approach has attracted more and more interest over the years and will undoubtedly be further enhanced and applied in the future. Hybrid modelling techniques based on a combination of LES and RANS approaches also fall into this category and are covered as well. The goal of the Workshop was to share the state of the art in DNS, LES and related techniques for the computation and modelling of turbulent and transitional flows. The respective papers highlight the latest advances in the prediction, understanding and control of turbulent flows in academic and industrial applications.

This volume presents selected papers from the IUTAM Symposium on Reynolds Number Scaling in Turbulent Flow, convened in Princeton, NJ, USA, September I1-13, 2002. The behavior ofturbulence at high Reynolds number is interesting from a fundamental point of view, in that most theories of turbulence make very specific predictions in the limit of infinite Reynolds number. From a more practical point of view, there exist many applications that involve turbulent flow where the Reynolds numbers are extremely large. For example, large vehicles such as submarines and commercial transports operate at Reynolds 9 numbers based on length ofthe order oft0 , and industrial pipe flows cover a 7 very wide range of Reynolds numbers up to 10 * Many very important applications of high Reynolds number flow pertain to atmospheric and other geophysical flows where extremely high Reynolds numbers are the rule rather than the exception, and the understanding of climate changes and the prediction of destructive weather effects hinges to some extent on our appreciation ofhigh-Reynolds number turbulence behavior. The important effects of Reynolds number on turbulence has received a great deal of recent attention. The objective of the Symposium was to bring together many of the world's experts in this area to appraise the new experimental results, discuss new scaling laws and turbulence models, and to enhance our mutual understanding of turbulence.

Design happens everywhere, whether in animate objects (e.g., dendritic lung structures, bacterial colonies, and corals), inanimate patterns (river basins, beach slope, and dendritic crystals), social dynamics (pedestrian traffic flows), or engineered systems (heat dissipation in electronic circuitry). This design in nature often takes on remarkably similar patterns, which can be explained under one unifying Constructal Law. This book explores the unifying power of the Constructal Law and its applications in all domains of design generation and evolution, ranging from biology and geophysics to globalization, energy, sustainability, and security.
The Constructal Law accounts for the universal tendency of flow systems to morph into evolving configurations that provide greater and easier access over time. The Constructal Law resolves the many and contradictory ad hoc statements of optimality, end design, and destiny in nature, such as minimum and maximum entropy production and minimum and maximum flow resistance, and also explains the designs that are observed and copied in biomimetics.
"Constructal Law and the Unifying Principle of Design" covers the fundamentals of Constructal Theory and Design, as well as presenting a variety ofstate-of-the-art applications. Experts from the biological, physical and social sciences demonstrate the unification of all design phenomena in nature, and apply this knowledge to novel designs in modern engineering, such as vascularization for self-healing and self-cooling materials for aircraft, and tree fins and cavities for heat transfer enhancement.

The book presents a state-of-the-art in environmental aerodynamics and the structural design of wind energy support structures, particularly from a modern computational perspective. Examples include real-life applications dealing with pollutant dispersion in the building environment, pedestrian-level winds, comfort levels, relevant legislation and remedial measures. Design methodologies for wind energy structures include reliability assessment and code frameworks.

This thesis first reveals the mechanism of Goertler instabilities and then demonstrates how transitions at hypersonic flows can be effectively controlled (either promoted or suppressed) with Goertler or Klebanoff modes. It focuses on understanding and controlling flow transitions from mild laminar to fully turbulent flows at high speeds-aspects that have become crucial at the dawn of an incredible era, in which hypersonic vehicles are becoming available. Once this occurs, it will be possible to travel from Beijing to Los Angeles within just 2 hours, and we will all live in a genuinely global village-and not just virtually, but physically. Goertler instabilities have often been used to promote flow transition in hypersonic vehicles. However, how Goertler instabilities are excited and how they evolve in hypersonic flows are questions that have yet to be answered.

Investigation of vortex wakes behind various aircraft, especially behind wide bodied and heavy cargo ones, is of both scientific and practical in terest. The vortex wakes shed from the wing's trailing edge are long lived and attenuate only atdistances of10-12kmbehindthe wake generating aircraft. The encounter of other aircraft with the vortex wake of a heavy aircraft is open to catastrophic hazards. For example, air refueling is adangerous operationpartly due to thepossibility of the receiver aircraft's encountering the trailing wake of the tanker aircraft. It is very important to know the behavior of vortex wakes of aircraft during theirtakeoff andlanding operations whenthe wakes canpropagate over the airport's ground surface and be a serious hazard to other depart ing or arriving aircraft. This knowledge can help in enhancing safety of aircraft's movements in the terminal areas of congested airports where the threat of vortex encounters limits passenger throughput. Theoreticalinvestigations of aircraft vortex wakes arebeingintensively performedinthe major aviationnations.Usedforthispurpose are various methods for mathematical modeling of turbulent flows: direct numerical simulation based on the Navier-Stokes equations, large eddy simulation using the Navier-Stokes equations in combination with subrigid scale modeling, simulation based on the Reynolds equations closed with a differential turbulence model. These approaches are widely used in works of Russian and other countries' scientists. It should be emphasized that the experiments in wind tunnels and studies of natural vortex wakes behind heavy and light aircraft in flight experiments are equally important.

In this book we will introduce the modeling process of turbulent particulate flows which are encountered in many engineering and environmental applications. These types of flows usually also involve heat and mass transfer and turbulence adds another dimension to the complexity of the problem and hence a rigorous mathematical treatment is usually required. This required mathematical background makes the learning curve for new research students and practicing engineers extremely steep. Therefore modeling process for new or existing problems is extremely slow and is usually restricted to minor improvements to the to the available models.

In this book we try to gather the required mathematical knowledge and introduce them more intuitively. Many numerical simulations of basic processes and equation will be given to provide the reader with a physical understanding of the different terms in the underlying equations. We will start the modeling process from a mesoscopic level which deals with the system of an intermediate length scale between the size of the atoms or molecules and the bulk of the material. This provides a unique opportunity for the reader to intuitively add different phenomena to their models and equipped with the necessary mathematical tools derive the final models for their problems.

In this book fluid mechanics and thermodynamics (F&T) are approached as interwoven, not disjoint fields. The book starts by analyzing the creeping motion around spheres at rest: Stokes flows, the Oseen correction and the Lagerstrom-Kaplun expansion theories are presented, as is the homotopy analysis. 3D creeping flows and rapid granular avalanches are treated in the context of the shallow flow approximation, and it is demonstrated that uniqueness and stability deliver a natural transition to turbulence modeling at the zero, first order closure level. The difference-quotient turbulence model (DQTM) closure scheme reveals the importance of the turbulent closure schemes' non-locality effects. Thermodynamics is presented in the form of the first and second laws, and irreversibility is expressed in terms of an entropy balance. Explicit expressions for constitutive postulates are in conformity with the dissipation inequality. Gas dynamics offer a first application of combined F&T. The book is rounded out by a chapter on dimensional analysis, similitude, and physical experiments.

Micro Transport Phenomena During Boiling reviews the new achievements and contributions in recent investigations at microscale. The content mainly includes (i) fundamentals for conducting investigations of micro boiling, (ii) microscale boiling and transport phenomena, (iii) boiling characteristics at microscale, (iv) some important applications of micro boiling transport phenomena. This book is intended for researchers and engineers in the field of micro energy systems, electronic cooling, and thermal management in various compact devices/systems at high heat removal and/or heat dissipation. Dr. Xiaofeng Peng, who had passed away on Sep. 10, 2009, was a professor at the Department of Thermal Engineering, Tsinghua University, China."

This book is devoted to an investigation of some important problems of mod ern filtering theory concerned with systems of 'any nature being able to per ceive, store and process an information and apply it for control and regulation'. (The above quotation is taken from the preface to 27]). Despite the fact that filtering theory is l'argely worked out (and its major issues such as the Wiener-Kolmogorov theory of optimal filtering of stationary processes and Kalman-Bucy recursive filtering theory have become classical) a development of the theory is far from complete. A great deal of recent activity in this area is observed, researchers are trying consistently to generalize famous results, extend them to more broad classes of processes, realize and justify more simple procedures for processing measurement data in order to obtain more efficient filtering algorithms. As to nonlinear filter ing, it remains much as fragmentary. Here much progress has been made by R. L. Stratonovich and his successors in the area of filtering of Markov processes. In this volume an effort is made to advance in certain of these issues. The monograph has evolved over many years, coming of age by stages. First it was an impressive job of gathering together the bulk of the impor tant contributions to estimation theory, an understanding and moderniza tion of some of its results and methods, with the intention of applying them to recursive filtering problems."

This book covers the latest research on porous materials at the submicron scale and inspires readers to better understand the porosity of materials, as well as to develop innovative new materials. A comprehensive range of materials are covered, including carbon-based and organic-based porous materials, porous anodic alumina, silica, and titania-based sol-gel materials. The fabrication, characterization, and applications of these materials are all explored, with applications ranging from sensors, thermoelectrics, catalysis, energy storage, to photovoltaics. Also of practical use for readers are chapters that describe the basics of porous silicon fabrication and its use in optical sensing and drug delivery applications; how thermal transport is affected in porous materials; how to model diffusion in porous materials; and a unique chapter on an innovative spectroscopic technique used to characterize materials' porosity. This is an ideal book for graduate students, researchers, and professionals who work with porous materials.

This book is written for researchers as well as engineers in an industrial environment. Following a longstanding tradition of the Les Houches Summer Schools, all chapters are pedagogically presented and accessible for graduate students. The book treats 2D and 3D turbulence from the experimental, theoretical and computational points of view. The reader will find, for example, comprehensive accounts of fully developed turbulence experiments, simulating deterministically coherent vortices formation, and statistical prediction of industrial flows, and a very complete review of 2D turbulence. Fundamental concepts like topological fluid dynamics in MHD flows or finite-time singularities of the Burgers, Euler and Navier--Stokes equations complete the volume.

What do combustion engines, fusion reactors, weather forecast, ocean ?ows, our sun, and stellar explosions in outer space have in common? Of course, the physics and the length and time scales are vastly di?erent in all cases, but it is alsowellknownthatinallofthem,onsomerelevantlengthscales,thematerial ?ows that govern the dynamical and/or secular evolution of the systems are chaotic and often unpredictable: they are said to be turbulent. In fact, the term "turbulence" is used for an enormous variety of p- nomena in very di?erent ?elds, including geophysics, astrophysics, and - gineering. Unfortunately, these communities do not talk to each other too often. Therefore, back in 2005, we organized a workshop on "Interdis- plinary Aspects of Turbulence" at the Ringberg Castle in the Bavarian Alps, to discuss topics such as the basic concepts of turbulence, the di?- ent approaches of modelling and simulations used in the various areas, and also possible tests. This workshop was a great success and the proceedings can be found on the Internet (www.mpa-garching.mpg.de/mpa/publications/ proceedings/proceedings-en.html) as well as pdf-?les of several of the talks presented (www.mpa-garching. mpg.de/hydro/Turbulence/).

This book gathers the proceedings of the Fifth Symposium on Hybrid RANS-LES Methods, which was held on March 19-21 in College Station, Texas, USA. The different chapters, written by leading experts, reports on the most recent developments in flow physics modelling, and gives a special emphasis to industrially relevant applications of hybrid RANS-LES methods and other turbulence-resolving modelling approaches. The book addresses academic researchers, graduate students, industrial engineers, as well as industrial R&D managers and consultants dealing with turbulence modelling, simulation and measurement, and with multidisciplinary applications of computational fluid dynamics (CFD), such as flow control, aero-acoustics, aero-elasticity and CFD-based multidisciplinary optimization. It discusses in particular advanced hybrid RANS-LES methods. Further topics include wall-modelled Large Eddy Simulation (WMLES) methods, embedded LES, and a comparison of the LES methods with both hybrid RANS-LES and URANS methods. Overall, the book provides readers with a snapshot on the state-of-the-art in CFD and turbulence modelling, with a special focus to hybrid RANS-LES methods and their industrial applications.

< div="">This textbook on Fundamentals of Gas Dynamics will help students with a background in mechanical and/or aerospace engineering and practicing engineers working in the areas of aerospace propulsion and gas dynamics by providing a rigorous examination of most practical engineering problems. The book focuses both on the basics and more complex topics such as quasi one dimensional flows, oblique shock waves, Prandtl Meyer flow, flow of steam through nozzles, etc. End of chapter problems, solved illustrations and exercise problems are presented throughout the book to augment learning. ^

This book presents a critical and modern analysis of the conceptual foundations of statistical mechanics as laid down in Boltzmann's works. The author emphasises the relation between microscopic reversibility and macroscopic irreversibility. Students will find a clear and detailed explanation of fundamental concepts such as equipartition, entropy and ergodicity. They will learn about Brownian motion, the modern treatment of the thermodynamic limit phase transitions, the microscopic and macroscopic theory of the coexistence of phases, statistical mechanics of stationary states, and fluctuations and dissipation in chaotic motions.

Experts in rheology and polymer processing present up-to-date, fundamental and applied information on the rheological properties of polymers, in particular those relevant to processing, contributing to the physical understanding and the mathematical modelling of polymer processing sequences. Basic concepts of non-Newtonian fluid mechanics, micro-rheological modelling and constitutive modelling are reviewed, and rheological measurements are described. Topics with practical relevance are debated, such as linear viscoelasticity, converging and diverging flows, and the rheology of multiphase systems. Approximation methods are discussed for the computer modelling of polymer melt flow. Subsequently, polymer processing technologies are studied from both simulation and engineering perspectives. Mixing, crystallization and reactive processing aspects are also included. Audience: An integrated and complete view of polymer processing and rheology, important to institutions and individuals engaged in the characterisation, testing, compounding, modification and processing of polymeric materials. Can also support academic polymer processing engineering programs.

This book gathers the best articles presented by researchers and industrial experts at the International Conference on "Innovative Design, Analysis and Development Practices in Aerospace and Automotive Engineering (I-DAD 2020)". The papers discuss new design concepts, and analysis and manufacturing technologies, with a focus on achieving improved performance by downsizing; improving the strength-to-weight ratio, fuel efficiency and operational capability at room and elevated temperatures; reducing wear and tear; addressing NVH aspects, while balancing the challenges of Euro VI/Bharat Stage VI emission norms, greenhouse effects and recyclable materials. Presenting innovative methods, this book is a valuable reference resource for professionals at educational and research organizations, as well as in industry, encouraging them to pursue challenging projects of mutual interest.

This thesis represents the first systematic description of the two-phase flow problem. Two-phase flows of volatile fluids in confined geometries driven by an applied temperature gradient play an important role in a range of applications, including thermal management, such as heat pipes, thermosyphons, capillary pumped loops and other evaporative cooling devices. Previously, this problem has been addressed using a piecemeal approach that relied heavily on correlations and unproven assumptions, and the science and technology behind heat pipes have barely evolved in recent decades. The model introduced in this thesis, however, presents a comprehensive physically based description of both the liquid and the gas phase. The model has been implemented numerically and successfully validated against the available experimental data, and the numerical results are used to determine the key physical processes that control the heat and mass flow and describe the flow stability. One of the key contributions of this thesis work is the description of the role of noncondensables, such as air, on transport. In particular, it is shown that many of the assumptions used by current engineering models of evaporative cooling devices are based on experiments conducted at atmospheric pressures, and these assumptions break down partially or completely when most of the noncondensables are removed, requiring a new modeling approach presented in the thesis. Moreover, Numerical solutions are used to motivate and justify a simplified analytical description of transport in both the liquid and the gas layer, which can be used to describe flow stability and determine the critical Marangoni number and wavelength describing the onset of the convective pattern. As a result, the results presented in the thesis should be of interest both to engineers working in heat transfer and researchers interested in fluid dynamics and pattern formation.

This volume contains the proceedings of the 2001 DLES4 workshop. It describes and discusses state-of-the-art modeling and simulation approaches for complex flows. Fundamental turbulence and modeling issues but also elements from modern numerical analysis are at the heart of this field of interest.

This book covers the experimental and theoretical study of convection in non-isothermal ferro-nanofluids (FNFs). Since FNFs are not transparent and magnetic fields are very sensitive to the shape of the boundary between magnetic and nonmagnetic media, special flow visualization techniques based on the use of thermo-sensitive liquid crystal films, infrared cameras, as well as local and integral temperature sensors are discussed in the book. This book considers several major configurations of convective chambers and the applied magnetic field. For each of them, the stability boundaries are determined theoretically and experimentally. The physical types of dominant instabilities and the characteristics of their interactions are subsequently established using linear and weakly non-linear hydrodynamic stability analyses and elements of bifurcation theory. The book also discusses the potential of using magnetically controlled ferro-nanofluids as a heat carrier in situations where heat removal by natural convection is not possible due to the lack of gravity (orbital stations) or extreme confinement (microelectronics). Researchers and practitioners working in the areas of fluid mechanics, hydrodynamic stability, and heat and mass transfer will benefit from this book.