Victor V. Kozlov – författare

Based on newinformation obtained on free microjets, this book explains the latest phenomenain flame evolution in the presence of a transverse acoustic field with roundand plane propane microjet combustion. It gives an overview of recentexperimental results on instability and dynamics of jets at low Reynoldsnumbers and provides the reader, step by step, with the milestones and recentadvances in jet flow stability and combustion. Readers will also discover aclarification of the differences between top-hat and parabolic round and planejet instability. Chapters demonstrate features of the interaction between jet and crossflow, andhow experimental data testify to similarities of the perturbed flow patterns oflaminar and turbulent round jets. A similar response of the jets to externalacoustic oscillations is shown, as well as the peculiarities of the effect of atransverse acoustic field on downstream evolution of round and plane macro- andmicrojets. Basic features of round and plane, macro and micro jets' evolutionaffected by initial conditions at the nozzle outlet and by environmentalperturbations are highlighted.Students of fluid mechanics will gain a solid foundation in hydrodynamicstability and combustion of subsonic jet flow and researchers will value thepresentation of special aspects of instability and transition. The work treatsboth theoretical and practical facets, and it includes supplementary materialsuch as PowerPoint multimedia notes based on results of laboratory scientificexperiments.

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.

The English teach mechanics as an experimental science, while on the Continent, it has always been considered a more deductive and a priori science. Unquestionably, the English are right. * H. Poincare, Science and Hypothesis Descartes, Leibnitz, and Newton As is well known, the basic principles of dynamics were stated by New­ ton in his famous work Philosophiae Naturalis Principia Mathematica, whose publication in 1687 was paid for by his friend, the astronomer Halley. In essence, this book was written with a single purpose: to prove the equivalence of Kepler's laws and the assumption, suggested to Newton by Hooke, that the acceleration of a planet is directed toward the center of the Sun and decreases in inverse proportion to the square of the distance between the planet and the Sun. For this, Newton needed to systematize the principles of dynamics (which is how Newton's famous laws appeared) and to state the "theory of fluxes" (analysis of functions of one variable). The principle of the equality of an action and a counteraction and the inverse square law led Newton to the theory of gravitation, the interaction at a distance. In addition, New­ ton discussed a large number of problems in mechanics and mathematics in his book, such as the laws of similarity, the theory of impact, special vari­ ational problems, and algebraicity conditions for Abelian integrals. Almost everything in the Principia subsequently became classic. In this connection, A. N.

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.

The English teach mechanics as an experimental science, while on the Continent, it has always been considered a more deductive and a priori science. Unquestionably, the English are right. * H. Poincare, Science and Hypothesis Descartes, Leibnitz, and Newton As is well known, the basic principles of dynamics were stated by New­ ton in his famous work Philosophiae Naturalis Principia Mathematica, whose publication in 1687 was paid for by his friend, the astronomer Halley. In essence, this book was written with a single purpose: to prove the equivalence of Kepler's laws and the assumption, suggested to Newton by Hooke, that the acceleration of a planet is directed toward the center of the Sun and decreases in inverse proportion to the square of the distance between the planet and the Sun. For this, Newton needed to systematize the principles of dynamics (which is how Newton's famous laws appeared) and to state the "theory of fluxes" (analysis of functions of one variable). The principle of the equality of an action and a counteraction and the inverse square law led Newton to the theory of gravitation, the interaction at a distance. In addition, New­ ton discussed a large number of problems in mechanics and mathematics in his book, such as the laws of similarity, the theory of impact, special vari­ ational problems, and algebraicity conditions for Abelian integrals. Almost everything in the Principia subsequently became classic. In this connection, A. N.

At the suggestion of the USSR National Committee of Theo­ retical and Applied Mechanios the International Union of Theo­ retical and Applied Meohanics made a deoision to organize the Second IUTAM Symposium on Laminar-Turbulent Transition in No­ vosibirsk. Professor Yanenko was entrusted to be the chairman of the scientific committee. It was proposed that about 100 scientists would participate in the Symposium and that 60 lectures and invited lectures would be delivered; as for the theme of the Symposium, it was devoted to experimental and theoretical stu­ dies of laminar-turbulent transition in fluids and gases, i.e. the physical problems of transition and mathematical modeling in shear flows. It was planned to lay a special emphasis on fundamental mechanisms of the transition process. The scienti­ fio committee approved of the scope of the Symposium having considered the changes in the directions of the stUdies which took place since the First Symposium. For example, there was singled out the problem of transformation of external distur­ bances into eigenoscillations of shear flows, i.e. the recep­ tivity problem which was only slightly touched upon at the First Symposium. A new section appeared devoted to the inter­ relation of the flow separation phenomenon and its stability. It was planned to focus the attention on the secondary instability at transition to turbulence at the non-linear stage of the flow breakdown as well as on the loss of stability and the disturbances development in 3-D flows.

Separated flows and jets are closely linked in a variety of applications. They are of great importance in various fields of fluid mechanics including vehicle efficiency, technical branches concerned with gas/liquid flows, atmospheric effects on various constructions, etc. Knowledge of the physics of separated flows and jets and the development of reliable control techniques are prerequisite for future progress in the field. These aspects were in focus during the IUTAM-Symposium which was held in Novosibirsk, 9-13 July, 1990. This volume contains a selection of papers presenting recent results of theoretical and numerical studies as well as experimental work on separated flows and jets. The topics include sub- and supersonic, laminar and turbulent separation as well as organized structures in separated flows and jets. The reader will find here the state of the art and major trends for research in this field of aero-hydrodynamics.

Starting from fundamentals of classical stability theory, an overview is given of the transition phenomena in subsonic, wall-bounded shear flows. At first, the consideration focuses on elementary small-amplitude velocity perturbations of laminar shear layers, i.e. instability waves, in the simplest canonical configurations of a plane channel flow and a flat-plate boundary layer. Then the linear stability problem is expanded to include the effects of pressure gradients, flow curvature, boundary-layer separation, wall compliance, etc. related to applications. Beyond the amplification of instability waves is the non-modal growth of local stationary and non-stationary shear flow perturbations which are discussed as well. The volume continues with the key aspect of the transition process, that is, receptivity of convectively unstable shear layers to external perturbations, summarizing main paths of the excitation of laminar flow disturbances. The remainder of the book addresses the instability phenomena found at late stages of transition. These include secondary instabilities and nonlinear features of boundary-layer perturbations that lead to the final breakdown to turbulence. Thus, the reader is provided with a step-by-step approach that covers the milestones and recent advances in the laminar-turbulent transition. Special aspects of instability and transition are discussed through the book and are intended for research scientists, while the main target of the book is the student in the fundamentals of fluid mechanics. Computational guides, recommended exercises, and PowerPoint multimedia notes based on results of real scientific experiments supplement the monograph. These are especially helpful for the neophyte to obtain a solid foundation in hydrodynamic stability.To access the supplementary material go to extras.springer.com and type in the ISBN for this volume.