This monograph is the result of my PhD thesis work in Computational Fluid Dynamics at the Massachusettes Institute of Technology under the supervision of Professor Earll Murman. A new finite element al gorithm is presented for solving the steady Euler equations describing the flow of an inviscid, compressible, ideal gas. This algorithm uses a finite element spatial discretization coupled with a Runge-Kutta time integration to relax to steady state. It is shown that other algorithms, such as finite difference and finite volume methods, can be derived using finite element principles. A higher-order biquadratic approximation is introduced. Several test problems are computed to verify the algorithms. Adaptive gridding in two and three dimensions using quadrilateral and hexahedral elements is developed and verified. Adaptation is shown to provide CPU savings of a factor of 2 to 16, and biquadratic elements are shown to provide potential savings of a factor of 2 to 6. An analysis of the dispersive properties of several discretization methods for the Euler equations is presented, and results allowing the prediction of dispersive errors are obtained. The adaptive algorithm is applied to the solution of several flows in scramjet inlets in two and three dimensions, demonstrat ing some of the varied physics associated with these flows. Some issues in the design and implementation of adaptive finite element algorithms on vector and parallel computers are discussed."

Prof. Newman is considered one of the great chemical engineers of his time. His reputation derives from his mastery of all phases of the subject matter, his clarity of thought, and his ability to reduce complex problems to their essential core elements. He is a member of the National Academy of Engineering, Washington, DC, USA, and has won numerous national awards including every award offered by the Electrochemical Society, USA. His motto, as known by his colleagues, is "do it right the first time." He has been teaching undergraduate and graduate core subject courses at the University of California, Berkeley (UC Berkeley), USA, since joining the faculty in 1966. His method is to write out, in long form, everything he expects to convey to his class on a subject on any given day. He has maintained and updated his lecture notes from notepad to computer throughout his career. This book is an exact reproduction of those notes. This book shows a clean and concise way on how to use different analytical techniques to solve equations of multiple forms that one is likely to encounter in most engineering fields, especially chemical engineering. It provides the framework for formulating and solving problems in mass transport, fluid dynamics, reaction kinetics, and thermodynamics through ordinary and partial differential equations. It includes topics such as Laplace transforms, Legendre's equation, vector calculus, Fourier transforms, similarity transforms, coordinate transforms, conformal mapping, variational calculus, superposition integrals, and hyperbolic equations. The simplicity of the presentation instils confidence in the readers that they can solve any problem they come across either analytically or computationally.

The study of materials which exhibit new and unconventional properties is of central importance for the devel- opment of advanced and refined technologies in many fields of engineering science. In this connection there has been a rapidly growing interest in real fluid effects on wave phenomena in the past few years. A prominent example is provided by Bethe-Zel'dovich-Thompson (BZT) fluids which have the distinguishing feature that they exhibit negative nonlinearity over a finite range of temperature and pressures in the pure vapour phase. However, two phase flows with and without phase change are an even richer source of new unexpected and previously thought impossible phenomena. Topics covered by this volume include waves in gases near the critical point, waves in retrograde fluids, temperature waves in superfluid helium and density waves in suspensions of particles in liquids. Clearly, the aim of the various contributions is twofold. First, they are intended to provide scientists and engineers working in these and related areas with an overview of various new physical phenomena as for example expansion shocks, sonic shocks, shock splitting, evaporation and liquafaction shocks and the experimental techniques needed to study these phenomena. Second, an attempt is made to discuss aspects of their mathematical modeling with special emphasis on properties which these phenomena have in common.

Out of the multitude of physical processes whose mechanisms depend on the interaction between the atmosphere and a lake, only those have been selected for discussion in this book which are inevitable in the mathematical modeling of lake hydrology and the microclimates, i.e., the meteorological regime over lakes and surrounding land. There are many reasons for a combined consideration of tile hydrological and meteorological aspects. First of all, they are essentially similar from a fluid mechanical point of view. Thus, the same phenomenon, viz., the turbulent plan etary boundary layer, is represented in lakes as the upper well-mixed water layer and in the atmosphere as the lower air layer directly influenced by thermal and dynamical action of the underlying surface. Processes at the air/water interface are equally important in energy transfer in both media. And finally, dynamical and thermal interaction between the adjoining atmospheric and lacustrine bound ary layers appears to be even stronger than between the upper and deep-water layers of a lake."

The most frequently used method for the numerical integration of parabolic differential equa tions is the method of lines, where one first uses a discretization of space derivatives by finite differences or finite elements and then uses some time-stepping method for the the solution of resulting system of ordinary differential equations. Such methods are, at least conceptually, easy to perform. However, they can be expensive if steep gradients occur in the solution, stability must be controlled, and the global error control can be troublesome. This paper considers a simultaneaus discretization of space and time variables for a one-dimensional parabolic equation on a relatively long time interval, called 'time-slab'. The discretization is repeated or adjusted for following 'time-slabs' using continuous finite element approximations. In such a method we utilize the efficiency of finite elements by choosing a finite element mesh in the time-space domain where the finite element mesh has been adjusted to steep gradients of the solution both with respect to the space and the time variables. In this way we solve all the difficulties with the classical approach since stability, discretization error estimates and global error control are automatically satisfied. Such a method has been discussed previously in 3] and 4]. The related boundary value techniques or global time integration for systems of ordinary differential equations have been discussed in several papers, see 12] and the references quoted therein."

This book is designed to fill a professional vacuum in the new field of advance, high-angle, vectored stealth aircraft. The subject matter presented in the volume has never before been investigated and presented as a unified field of study because it covers entirely new fields and because specialized fragments of this unified field are scattered throughout literature in specific problems. The book is of interest to aeronautical and mechanical engineers, electrical and control engineers, aerospace industry, USAF, US Navy, NASA, pilots and instructors.

From the Preface:"The purpose of this book is to present and apply a language and to discuss methods which make it very convenient to exploit such analogies, and which are uniquely suited to describe and explain non-equilibrium phenomena in a rich variety of many-particle systems: the language of time correlation functions and linear response theory."

The numerical simulation of the Euler equations of Fluid Dynamics has been these past few years a challenging problem both for research scientists and aerospace engineers. The increasing interest of more realistic models such as the Euler equations originates in Aerodynamics and also Aerothermics where aerospace applications such as military aircrafts and also space vehicles require accurate and efficient Euler solvers (which can be extended to more complicated modelisations including non-equilibrium chemistry) for su personic and hypersonic flows at high angles of attack and Mach number regimes involving strong shocks and vorticity. This book contains the proceedings of the GAMM Workshop on the Numerical Simu lation of Compressible Euler Flows. that W: LS held at INRIA, Rocquencourt (France), on June 10-13, 1986. The purpose of this event was to compare in terms of accuracy and efficiency several codes for solving compressible inviscid, mainly steady, Euler flows. This workshop was a sequel of the GAMM workshop held in 1979 in Stockholm; this time, though, because of the present strong activity in numerical methods for the Euler equat.ions, the full-potential approach was not included. Since 1979, other Eulpr workshops have been organised, sev eral of them focussed on airfoil calculations; however, many recently derived methods were not presented at these workshops, because, among other reasons, the methods were not far enough developed, or had not been applied to flow problems of sufficient complexity. In fact, the 1986 GAMM workshop scored very high as regards to the novelty of methods."

The last decade has seen a dramatic increase of our abilities to solve numerically the governing equations of fluid mechanics. In design aerodynamics the classical potential-flow methods have been complemented by higher modelling-level methods. Euler solvers, and for special purposes, already Navier-Stokes solvers are in use. The authors of this book have been working on the solution of the Euler equations for quite some time. While the first two of us have worked mainly on algorithmic problems, the third has been concerned off and on with modelling and application problems of Euler methods. When we started to write this book we decided to put our own work at the center of it. This was done because we thought, and we leave this to the reader to decide, that our work has attained over the years enough substance in order to justify a book. The problem which we soon faced, was that the field still is moving at a fast pace, for instance because hyper sonic computation problems became more and more important."

These proceedings contain original (refereed) research articles by specialists from many countries, on a wide variety of aspects of Navier-Stokes equations. Additionally, 2 survey articles intended for a general readership are included: one surveys the present state of the subject via open problems, and the other deals with the interplay between theory and numerical analysis.

Gesamtwerk: In diesem Werk der beiden bedeutenden Aerodynamiker wird das gesamte Gebiet der Flugzeugaerodynamik von den Grundlagen bis zu den Entwicklungen der 60er Jahre des 20. Jahrhunderts in klarer, ingenieursgemasser Form dargestellt. Das Hauptgewicht liegt dabei auf den physikalisch und technisch wichtigen Sachverhalten. Die erlauterten Berechnungsverfahren werden durch zahlreiche Beispielrechnungen und Abbildungen veranschaulicht sowie durch Vergleich mit experimentellen Werten uberpruft. Zweiter Band: Im zweiten Band wird die Theorie des Tragflugels endlicher Spannweite bei inkompressibler Stroemung, die Theorie des Tragflugels bei kompressibler Stroemung, die Aerodynamik des Rumpfes, der Flugel-Rumpf-Anordnung, der Leitwerke sowie der Ruder und Klappen behandelt.

For the last ten years, there has been an ever-increasing awareness that fluid motion and transport processes influenced by buoyancy are of interest in many fields of science and technology. In particular, a lot of research has been devoted to the oscillatory behaviour of metallic melts (low-Pr fluids) due to the very crucial impact of such flow oscillations on the quality of growing crystals, semi-conductors or metallic alloys, for advanced technology applications. Test cases on the 2D oscillatory convection in differentially heated cavities containing low-Pr fluids have been defined by the organizing committee, and proposed to the community in 1987. The GAMM-Worshop was attended by 55 scientists from 12 countries, in Oct. 1988 in Marseille (France). Twenty-eight groups contributed to the mandatory cases coming from France (12), other European countries (7) and other countries: USA, Japan and Australia (9). Several groups also presented solutions of various related problems such as accurate determination of the threshold for the onset of oscillations, thermocapillary effect in open cavities, and 3D simulations. Period doubling, quasi- periodic behaviour, reverse transition and hysteresis loops have been reported for high Grashof numbers in closed cavities. The workshop was also open to complementary contributions (5), from experiments and theory (stability and bifurcation analysis). The book contains details about the various methods employed and the specific results obtained by each contributor.

In recent years the subject of relativistic fluid dynamics has found substantial applications in astrophysics and cosmology (theories of gravitational collapse, models of neutron stars, galaxy formation), as well as in plasma physics (relativistic fluids have been considered as models for relativistic particle beams) and nuclear physics (relativistic fluids are currently used in the analysis of the heavy ion reactions). Modern methods of analysis and differential geometry have now also been introduced. The International C.I.M.E. Course brought together expertise and interest from several areas (astrophysics, plasma physics, nuclear physics, mathematical methods) to create an appropriate arena for discussion and exchange of ideas. The main lecture courses introduced the most significant aspects of the subject and were delivered by leading specialists. The notes of these have been written up for this volume and constitute an up-to-date and thorough treatment of these topics. Several contributions from the seminars on specialized topics of complementary interest to the courses are also included.

Gesamtwerk: In diesem Werk der beiden bedeutenden Aerodynamiker wird das gesamte Gebiet der Flugzeugaerodynamik von den Grundlagen bis zu den Entwicklungen der 60er Jahre des 20.Jahrhunderts in klarer, ingenieursgemasser Form dargestellt. Das Hauptgewicht liegt dabei auf den physikalisch und technisch wichtigen Sachverhalten. Die erlauterten Berechnungsverfahren werden durch zahlreiche Beispielrechnungen und Abbildungen veranschaulicht sowie durch Vergleich mit experimentellen Werten uberpruft. Erster Band: Der erste Band behandelt die Grundlagen der Stromungsmechanik einschliesslich der Gasdynamik und der Grenzschichttheorie, und zwar mit besonderer Betonung der Anwendungen in der Flugtechnik. Ausserdem enthalt der erste Band die Profiltheorie, d.h. den ersten Teil der Aerodynamik des Tragflugels."

The papers included in this proceedings volume are mostly original research papers, dealing with life-span of waves, nonlinear interaction of waves, and various applications to fluid mechanics.

In full multigrid methods for elliptic difference equations one works on a sequence of meshes where a number of pre- and/or postsmoothing steps are performed on each level. As is well known these methods can converge very fast on problems with a smooth solution and a regular mesh, but the rate of convergence can be severely degraded for problems with unisotropy or discontinuous coefficients unless some form of robust smoother is used. Also problems can arise with the increasingly coarser meshes because for some types of discretization methods, coercivity may be lost on coarse meshes and on massively parallel computers the computation cost of transporting information between computer processors devoted to work on various levels of the mesh can dominate the whole computing time. For discussions about some of these problems, see (11). Here we propose a method that uses only two levels of meshes, the fine and the coarse level, respec tively, and where the corrector on the coarse level is equal to a new type of preconditioner which uses an algebraic substructuring of the stiffness matrix. It is based on the block matrix tridiagonal structure one gets when the domain is subdivided into strips. This block-tridiagonal form is used to compute an approximate factorization whereby the Schur complements which arise in the recursive factorization are approximated in an indirect way, i. e."

This valuable volume provides a broad understanding of the main computational techniques used for processing reclamation of fluid and solid mechanics. The aim of these computational techniques is to reduce and eliminate the risks of mechanical systems failure in hydraulic machines. Using many computational methods for mechanical engineering problems, the book presents not only a platform for solving problems but also provides a wealth of information to address various technical aspects of troubleshooting of mechanical system failure. The focus of the book is on practical and realistic fluids engineering experiences. Many photographs and figures are included, especially to illustrate new design applications and new instruments.

This textbook presents numerical solution techniques for incompressible turbulent flows that occur in a variety of scientific and engineering settings including aerodynamics of ground-based vehicles and low-speed aircraft, fluid flows in energy systems, atmospheric flows, and biological flows. This book encompasses fluid mechanics, partial differential equations, numerical methods, and turbulence models, and emphasizes the foundation on how the governing partial differential equations for incompressible fluid flow can be solved numerically in an accurate and efficient manner. Extensive discussions on incompressible flow solvers and turbulence modeling are also offered. This text is an ideal instructional resource and reference for students, research scientists, and professional engineers interested in analyzing fluid flows using numerical simulations for fundamental research and industrial applications.

From the preface: Fluid dynamics is an excellent example of how recent advances in computational tools and techniques permit the rapid advance of basic and applied science. The development of computational fluid dynamics (CFD) has opened new areas of research and has significantly supplemented information available from experimental measurements. Scientific computing is directly responsible for such recent developments as the secondary instability theory of transition to turbulence, dynamical systems analyses of routes to chaos, ideas on the geometry of turbulence, direct simulations of turbulence, three-dimensional full-aircraft flow analyses, and so on. We believe that CFD has already achieved a status in the tool-kit of fluid mechanicians equal to that of the classical scientific techniques of mathematical analysis and laboratory experiment.

"I do not think at all that I am able to present here any procedure of investiga tion that was not perceived long ago by all men of talent; and I do not promise at all that you can find here anything_ quite new of this kind. But I shall take pains to state in clear words the pules and ways of investigation which are followed by ahle men, who in most cases are not even conscious of foZlow ing them. Although I am free from illusion that I shall fully succeed even in doing this, I still hope that the little that is present here may please some people and have some application afterwards. " Bernard Bolzano (Wissenschaftslehre, 1929) The following book results from aseries of lectures on the mathematical theory of turbulence delivered by the author at the Purdue University School of Aeronautics and Astronautics during the past several years, and represents, in fact, a comprehensive account of the author's work with his graduate students in this field. It was my aim in writing this book to give to engineers and scientists a mathematical feeling for a subject, which because of its nonlinear character has resisted mathematical analysis for many years. On account vii i of its refractory nature this subject was categorized as one of seven "elementary catastrophes." The material presented here is designed for a first graduate course in turbulence. The complete course has been taught in one semester."

With the advent of super computers during the last ten years, the numerical simulation of viscous fluid flows modeled by the Navier-Stokes equations is becoming a most useful tool in Aircraft and Engine Design. In fact, compressible Navier-Stokes solvers tend to constitute the basic tools for many industrial applications occuring in the simulation of very complex turbulent and combustion phenomena. In Aerospace Engineering, as an exemple, their mathematical modelization requires reliable and robust methods for solving very stiff non linear partial differential equations. For the above reasons, it was clear that a workshop on this topic would be of interest for the CFD community in order to compare accuracy and efficiency of Navier-Stokes solvers on selected external and internal flow problems using different numerical approaches. The workshop was held on 4-6 December 1985 at Nice, France and organized by INRIA with the sponsorship of the GAMM Committee on Numerical Methods in Fluid Mechanics.

Turbulent reactive flows are of common occurrance in combustion engineering, chemical reactor technology and various types of engines producing power and thrust utilizing chemical and nuclear fuels. Pollutant formation and dispersion in the atmospheric environment and in rivers, lakes and ocean also involve interactions between turbulence, chemical reactivity and heat and mass transfer processes. Considerable advances have occurred over the past twenty years in the understanding, analysis, measurement, prediction and control of turbulent reactive flows. Two main contributors to such advances are improvements in instrumentation and spectacular growth in computation: hardware, sciences and skills and data processing software, each leading to developments in others. Turbulence presents several features that are situation-specific. Both for that reason and a number of others, it is yet difficult to visualize a so-called solution of the turbulence problem or even a generalized approach to the problem. It appears that recognition of patterns and structures in turbulent flow and their study based on considerations of stability, interactions, chaos and fractal character may be opening up an avenue of research that may be leading to a generalized approach to classification and analysis and, possibly, prediction of specific processes in the flowfield. Predictions for engineering use, on the other hand, can be foreseen for sometime to come to depend upon modeling of selected features of turbulence at various levels of sophistication dictated by perceived need and available capability.