A derivation of the averaged balance equations of fluid mechanics is presented including compressibility with alternative equations of state, viscous and thermal dissipation contributions, stream tube end boundary motion, and chemical reaction. Explicit utilization of the energy equation, or enthalpy equation in combination with the linear momentum and mass balances is investigated. Both the vorticity and Bernouilli equations are provided in alternative forms with thermodynamic energy assumptions to be used in engineering analysis and to discern assumptions.

This book systematically presents the consolidated findings of the phenomenon of self-organization observed during the onset of thermoacoustic instability using approaches from dynamical systems and complex systems theory. Over the last decade, several complex dynamical states beyond limit cycle oscillations such as quasiperiodicity, frequency-locking, period-n, chaos, strange non-chaos, and intermittency have been discovered in thermoacoustic systems operated in laminar and turbulent flow regimes. During the onset of thermoacoustic instability in turbulent systems, an ordered acoustic field and large coherent vortices emerge from the background of turbulent combustion. This emergence of order from disorder in both temporal and spatiotemporal dynamics is explored in the contexts of synchronization, pattern formation, collective interaction, multifractality, and complex networks. For the past six decades, the spontaneous emergence of large amplitude, self-sustained, tonal oscillations in confined combustion systems, characterized as thermoacoustic instability, has remained one of the most challenging areas of research. The presence of such instabilities continues to hinder the development and deployment of high-performance combustion systems used in power generation and propulsion applications. Even with the advent of sophisticated measurement techniques to aid experimental investigations and vast improvements in computational power necessary to capture flow physics in high fidelity simulations, conventional reductionist approaches have not succeeded in explaining the plethora of dynamical behaviors and the associated complexities that arise in practical combustion systems. As a result, models and theories based on such approaches are limited in their application to mitigate or evade thermoacoustic instabilities, which continue to be among the biggest concerns for engine manufacturers today. This book helps to overcome these limitations by providing appropriate methodologies to deal with nonlinear thermoacoustic oscillations, and by developing control strategies that can mitigate and forewarn thermoacoustic instabilities. The book is also beneficial to scientists and engineers studying the occurrence of several other instabilities, such as flow-induced vibrations, compressor surge, aeroacoustics and aeroelastic instabilities in diverse fluid-mechanical environments, to graduate students who intend to apply dynamical systems and complex systems approach to their areas of research, and to physicists who look for experimental applications of their theoretical findings on nonlinear and complex systems.

This updated new edition provides an introduction to the field of thermoacoustics. All of the key aspects of the topic are introduced, with the goal of helping the reader to acquire both an intuitive understanding and the ability to design hardware, build it, and assess its performance. Weaving together intuition, mathematics, and experimental results, this text equips readers with the tools to bridge the fields of thermodynamics and acoustics. At the same time, it remains firmly grounded in experimental results, basing its discussions on the distillation of a body of experiments spanning several decades and countries. The book begins with detailed treatment of the fundamental physical laws that underlie thermoacoustics. It then goes on to discuss key concepts, including simple oscillations, waves, power, and efficiency. The remaining portions of the book delve into more advanced topics and address practical concerns in applications chapters on hardware and measurements. With its careful progression and end-of-chapter exercises, this book will appeal to graduate students in physics and engineering as well as researchers and practitioners in either acoustics or thermodynamics looking to explore the possibilities of thermoacoustics. This revised and expanded second edition has been updated with an eye to modern technology, including computer animations and DeltaEC examples.

Oscillations of gas and/or liquid columns in a flow channel can lead to various phenomena such as Stirling cycle heat engines, pulse tube refrigerators, as well as thermally induced gas oscillations like Sondhauss tube and Rijke tube. Although those phenomena may look different from each other, they can be universally described by the concepts of work flow and heat flow. Work flow stands for the acoustic power used in acoustics. Heat flow is the energy flow associated with the hydrodynamic transport of entropy. These energy flows help us to understand the thermoacoustic phenomena and construct acoustical heat engines.The book aims to provide a comprehensive overview of how the oscillations of gas and/or liquid columns make possible the mutual energy conversions between work flow and heat flow through thermal interactions between fluids and channel walls. The thermodynamic aspects of energy flows are highlighted by introducing Lagrangian point of view to explain the thermodynamic cycles that the fluid parcels undergo. The relevant experimental results are provided to verify the theoretical analysis based on basic equations of fluid dynamics.

Fluid Mechanics, Second Edition deals with fluid mechanics, that is, the theory of the motion of liquids and gases. Topics covered range from ideal fluids and viscous fluids to turbulence, boundary layers, thermal conduction, and diffusion. Surface phenomena, sound, and shock waves are also discussed, along with gas flow, combustion, superfluids, and relativistic fluid dynamics. This book is comprised of 16 chapters and begins with an overview of the fundamental equations of fluid dynamics, including Euler's equation and Bernoulli's equation. The reader is then introduced to the equations of motion of a viscous fluid; energy dissipation in an incompressible fluid; damping of gravity waves; and the mechanism whereby turbulence occurs. The following chapters explore the laminar boundary layer; thermal conduction in fluids; dynamics of diffusion of a mixture of fluids; and the phenomena that occur near the surface separating two continuous media. The energy and momentum of sound waves; the direction of variation of quantities in a shock wave; one- and two-dimensional gas flow; and the intersection of surfaces of discontinuity are also also considered. This monograph will be of interest to theoretical physicists.

This e-book is a compilation of papers presented at the 6th Mechanical Engineering Research Day (MERD'19) - Kampus Teknologi UTeM, Melaka, Malaysia on 31 July 2019.

The boundary element method (BEM) is a modern numerical techniquewhich has enjoyed increasing popularity over the last two decades,and is now an established alternative to traditional computationalmethods of engineering analysis. The main advantage of the BEM isits unique ability to provide a complete solution in terms ofboundary values only, with substantial savings in modelling effort. This two-volume book set is designed to provide the readers with acomprehensive and up-to-date account of the boundary element methodand its application to solving engineering problems. Each volume isa self-contained book including a substantial amount of materialnot previously covered by other text books on the subject. Volume 1covers applications to heat transfer, acoustics, electrochemistryand fluid mechanics problems, while volume 2 concentrates on solidsand structures, describing applications to elasticity, plasticity,elastodynamics, fracture mechanics and contact analysis. The earlychapters are designed as a teaching text for final yearundergraduate courses. Both volumes reflect the experience of theauthors over a period of more than twenty years of boundary element research. This volume, Applications in Thermo-Fluids and Acoustics, provides acomprehensive presentation of the BEM from fundamentals to advancedengineering applications and encompasses: Steady and transient heat transfer Potential and viscous fluid flows Frequency and time-domain acoustics Corrosion and other electrochemical problems. A unique feature of this book is an in-depth presentation of BEMformulations in all the above fields, including detaileddiscussions of the basic theory, numerical algorithms and practicalengineering applications of the method. Written by an internationally recognised authority in the field,this is essential reading for postgraduates, researchers andpractitioners in civil, mechanical and chemical engineering andapplied mathematics.

The text is richly illustrated, lightly written and more wide-ranging than Volume 1. A comprehensive treatment of fluid-structure interactions involving axial flow and slender structures, such as piping, human veins, aircraft, nuclear reactor fuel and submarine skins. The emphasis is on fundamentals, particularly on the physical understanding and underlying mechanisms, as well as on applications.This book will be invaluable for researchers, professional engineers, applied scientists and students involved in the design, study or operation or systems involving fluid flow, internal or external structures, wind or ocean currents - Emphasizes real-world analysis of problems encountered in the field and presents their solutions - A practical and thorough literature review of over 1400 references, an excellent reference document - Bridges the gap between academic researchers and practitioners in industry

This book presents contributions to the 19th biannual symposium of the German Aerospace Aerodynamics Association (STAB) and the German Society for Aeronautics and Astronautics (DGLR). The individual chapters reflect ongoing research conducted by the STAB members in the field of numerical and experimental fluid mechanics and aerodynamics, mainly for (but not limited to) aerospace applications, and cover both nationally and EC-funded projects. Special emphasis is given to collaborative research projects conducted by German scientists and engineers from universities, research-establishments and industries. By addressing a number of cutting-edge applications, together with the relevant physical and mathematics fundamentals, the book provides readers with a comprehensive overview of the current research work in the field. Though the book’s primary emphasis is on the aerospace context, it also addresses further important applications, e.g. in ground transportation and energy.