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Books > Science & Mathematics > Physics > Classical mechanics > Fluid mechanics
The GAMM Committee for Numerical Methods in Fluid Mechanics
organizes workshops which should bring together experts of a narrow
field of computational fluid dynamics (CFD) to exchange ideas and
experiences in order to speed-up the development in this field. In
this sense it was suggested that a workshop should treat the
solution of CFD problems on vector computers. Thus we organized a
workshop with the title "The efficient use of vector computers with
emphasis on computational fluid dynamics." The workshop took place
at the Computing Centre of the University of Karlsruhe, March
13-15,1985. The participation had been restricted to 22 people of 7
countries. 18 papers have been presented. In the announcement of
the workshop we wrote: "Fluid mechanics has actively stimulated the
development of superfast vector computers like the CRAY's or CYBER
205. Now these computers on their turn stimulate the development of
new algorithms which result in a high degree of vectorization
(sca1ar/vectorized execution-time). But with 3-D problems we
quickly reach the limit of present vector computers. If we want
e.g. to solve a system of 6 partial differential equations (e.g.
for u, v, w, p, k, or for the vectors u, curl u) on a 50x50x50 grid
we have 750.000 unknowns and for a 4th order difference method we
have circa 60 million nonzero coefficients in the highly sparse
matrix. This characterizes the type of problems which we want to
discuss in the workshop.""
6. 2 Creeping viscous flow in a semi-infinite channel 140 6. 3
Poiseuille flow in tubes of circular cross-section 144 6. 4 Motion
of a Newtonian liquid between two coaxial cylinders 148 151 6. 5
Bodies in liquids 6. 6 liquid flow and intermolecular forces 154
Non-Newtonian liquids 157 6. 7 6. 8 Viscometers 160 Chapter 7
Surface effects 163 7. 1 Introduction 163 7. 2 Excess surface free
energy and surface tension of liquids 163 7. 3 The total surface
energy of liquids 167 7. 4 Surface tension and intermolecular
forces 168 7. 5 Solid surfaces 171 7. 6 Specific surface free
energy and the intermolecular potential 172 7. 7 liquid surfaces
and the Laplace-Young equation 174 7. 8 liquid spreading 178 7. 9
Young's relation 181 7. 10 Capillary effects 184 7. 11 The sessile
drop 187 7. 12 Vapour pressure and liquid-surface curvature 189 7.
13 The measurement of surface free energies 191 Chapter 8 High
polymers and liquid crystals 197 8. 1 Introduction 197 8. 2 High
polymers 197 8. 3 The mechanisms of polymerisation 198 8. 4 The
size and shape of polymer molecules 199 8. 5 The structure of solid
polymers 201 8. 6 The glass transition temperature 203 8. 7 Young's
modulus of solid polymers 205 Stress-strain curves of polymers 8. 8
206 8. 9 Viscous flow in polymers 209 liquid crystals 8.
This investigation is an outgrowth of my doctoral dissertation at
Princeton University. I am particularly grateful to Professors
George F. Pinder and William G. Gray of Princeton for their advice
during both my research and my writing. I believe that
finite-element collocation holds promise as a numer ical scheme for
modeling complicated flows in porous media. However, there seems to
be a "conventional wisdom" maintaining that collocation is
hopelessly beset by oscillations and is, in some way, fundamentally
inappropriate for multiphase flows. I hope to dispel these
objections, realizing that others will remain for further work. The
U. S. National Science Foundation funded much of this study through
grant number NSF-CEE-8111240. TABLE OF CONTENTS ABSTRACT ;;
FOREWORD ;; ; CHAPTER ONE. THE PHYSICAL SYSTEM. 1.1 Introduction. 1
1.2 The reservoir and its contents. 5 1.3 Reservoir mechanics. 9
1.4 Supplementary constraints. 18 1.5 Governing equations. 26
CHAPTER TWO. REPRESENTING FLUID-PHASE BEHAVIOR. 39 2.1
Thermodynamics of the fluid system. 40 2.2 Standard
equation-of-state methods. 45 2.3 Maxwell-set interpolation.
The scope of the present book is to offer the most efficient tools
for the vectorization of serial computer programs. Here, by
vectorization we understand the adaptation of computer programs to
the special architecture of modern available vector computers to
exploit fully their potential, which will often result in
remarkable performance improvements. The book is written primarily
for users working in the various fields of computational physics,
for scientists as well as for programmers running their jobs on a
vector computer. The text may, however, also be of value to those
who are interested in numerical algorithms. Although the examples
discussed in chapter 9 have been taken from Computational Fluid
Dynamics, the numerical methods are well-known, and are applied in
many fields of Computational Physics. The book is divided into four
parts. After a short introduction which outlines the limits of
conventional serial computers in contrast to the possibilities
offered by the new vector machines, the second part is addressed to
the discussion of some main features of existing computer
architectures. We restrict ourselves to the vector computers
CRAY-1S and CDC-CYBER 205, although, in the meantime, many vector
and parallel computers and array processors are available such as
DENELCOR's Heterogeneous Element Processor (HEP), ICL's Distributed
Array Processor (DAP), SPERRY UNIVAC's Array Processing System
(APS), STAR TECHNOLOGIES ST-l00, FLOATING POINT SYSTEMS' Array
Processor (FPS), FUJITSU's FACOM VP-l00 and VP-200, HITACHI's
Integrated Array Processor (lAP), HITACHI's S 810/10 and S 810/20
and others.
Applied Mathematics is the art of constructing mathematical models
of observed phenomena so that both qualitative and quantitative
results can be predicted by the use of analytical and numerical
methods. Theoretical Mechanics is concerned with the study of those
phenomena which can be ob served in everyday life in the physical
world around us. It is often characterised by the macroscopic
approach which allows the concept of an element or particle of
material, small compared to the dimensions of the phenomena being
modelled, yet large compared to the molecular size of the material.
Then atomic and molecular phenomena appear only as quantities
averaged over many molecules. It is therefore natural that the
mathemati cal models derived are in terms of functions which are
continuous and well behaved, and that the analytical and numerical
methods required for their development are strongly dependent on
the theory of partial and ordinary differential equations. Much
pure research in Mathematics has been stimu lated by the need to
develop models of real situations, and experimental observations
have often led to important conjectures and theorems in Analysis.
It is therefore important to present a careful account of both the
physical or experimental observations and the mathematical analysis
used. The authors believe that Fluid Mechanics offers a rich field
for il lustrating the art of mathematical modelling, the power of
mathematical analysis and the stimulus of applications to readily
observed phenomena."
The concept of vorticity is of central importance in fluid
mechanics and the change and variability of atmospheric flow is
dominated by transient vortices of different time- and space
scales. Of particular importance are the most in- tense vortices
such as hurricanes, typhoons and tornadoes which are associated
with extreme and hazardous weather events of great concern to
society. In recent years the un- derstanding of these phenomena has
grown due to increased and improved surveillance by satellites and
aircraft as well as by numerical modelling and simulation,
theoretical studies and laboratory experiments. The symposium on
"Intense Atmospheric Vortices" was held at the European Centre for
Medium Range Weather Forecasts (ECMWF), Reading, England, July
14-17, 1981. The subject area of the Symposium was concerned with
observational work, experimental models, theoretical and numerical
studies in- volving hurricanes, typhoons, tornadoes and related
pheno- mena. The aim was to bring together experts on these meteo-
rological processes and on the fundamental fluid-dynamic mechanisms
for vorticity intensification from all parts of the world.
Thirtyfour scientists participated in the Sympo- sium, including
more than half of those leading world ex- perts in the field whom
the organizers had invited.
The content of this book is based, largely, on the core curriculum
in geophys ical fluid dynamics which land my colleagues in the
Department of Geophysical Sciences at The University of Chicago
have taught for the past decade. Our purpose in developing a core
curriculum was to provide to advanced undergraduates and entering
graduate students a coherent and systematic introduction to the
theory of geophysical fluid dynamics. The curriculum and the
outline of this book were devised to form a sequence of courses of
roughly one and a half academic years (five academic quarters) in
length. The goal of the sequence is to help the student rapidly
advance to the point where independent study and research are
practical expectations. It quickly became apparent that several
topics (e. g., some aspects of potential theory) usually thought of
as forming the foundations of a fluid-dynamics curriculum were
merely classical rather than essential and could be, however sadly,
dispensed with for our purposes. At the same time, the diversity of
interests of our students is so great that no curriculum can truly
be exhaust ive in such a curriculum period. It seems to me that the
best that can be achieved as a compromise is a systematic
introduction to some important segment of the total scope of
geophysical fluid dynamics which is illustrative of its most
fruitful methods."
The book provides an original approach in the research of
structural analysis of free developed shear compressible turbulence
at high Reynolds number on the base of direct numerical simulation
(DNS) and instability evolution for ideal medium (integral
conservation laws) with approximate mechanism of dissipation (FLUX
dissipative monotone "upwind" difference schemes) and does not use
any explicit sub-grid approximation and semi-empirical models of
turbulence. Convective mixing is considered as a principal part of
conservation law.Appropriate hydrodynamic instabilities (free
developed shear turbulence) are investigated from unique point of
view. It is based on the concept of large ordered structures with
stochastic core of small scale developed turbulence ("turbulent
spot"). Decay of "turbulent spot" are simulated by Monte Carlo
method. Proposed approach is based on two hypotheses: statistical
independence of the characteristic of large ordered structures
(LOS) and small-scale turbulence (ST) "and" weak influence of
molecular viscosity (or more generally, dissipative mechanism) on
properties of large ordered structures.Two versions of
instabilities, due to Rayleigh-Taylor and Richtmyer-Meshkov are
studied detail by the three-dimensional calculations, extended to
the large temporal intervals, up to turbulent stage and
investigation turbulent mixing zone (TMZ).The book covers both the
fundamental and practical aspects of turbulence and instability and
summarizes the result of numerical experiments conducted over 30
years period with direct participation of the author.In the book
are cited the opinions of the leading scientists in this area of
research: Acad. A S Monin (Russia), Prof. Y Nakamura (Japan, Nagoya
University) and Prof. F Harlow (USA, Los-Alamos).
Ever since airplane speeds started to approach the speed of sound,
the study of compressible flow problems attracted much talent and
support in the major indus trialized countries. Today, gas dynamics
is a mature branch of science whose many aspects and applications
are much too numerous to be mastered by a single person or to be
described in a few volumes. This book commemorates the 70th
birthday of a great pioneer and teacher of gas dynamics, Dr. Klaus
Oswatitsch, Professor of Fluid Mechanics at the Technical
University of Vienna and former Director of the Institute for
Theoretical Gas Dyna mics, Deutsche Forschungs-und Versuchsanstalt
fUr Luft-und Raumfahrt. Several reasons motivated us to prepare an
English translation of Oswatitsch's selected sci entific papers.
First, we hope that a book containing his major papers will be wel
come as a valuable reference text in gas dynamics. Oswatitsch's
work is frequently used in the literature in one form or another,
but it is usually quite time-consuming for the English speaking
reader to consult the original texts. As a result, reference to and
understanding of his papers is often incomplete. For example,
Oswatitsch's formulation of the equivalence rule hardly ever is
quoted in recent textbooks, al though it preceded declassification
of Whitcomb's results by several years. Further more, his papers
contain much information, which has not yet been fully appreciated
in the Anglo-American literature."
Provides unified coverage of computational heat transfer and fluid
dynamics. Covers basic concepts and then applies computational
methods for problem analysis and solution. Contains new chapters on
mesh generation and computer modeling of turbulent flow. Includes
ANSYS, STAR CCM+, and COMSOL CFD code and tutorials in the
appendix. Includes a Solutions Manual for instructor use.
This book presents the mathematical theory of turbulence to engineers and physicists, and the physical theory of turbulence to mathematicians. It is the result of many years of research by the authors to analyze turbulence using Sobolev spaces and functional analysis. In this way the authors have recovered parts of the conventional theory of turbulence, deriving rigorously from the Navier-Stokes equations that had been arrived at earlier by phenomenological arguments. Appendices give full details of the mathematical proofs and subtleties.
The aim of this book is to bring together classical and recent
developments in the particular field of Newtonian flow at low
Reynolds numbers. The methods are developed from first principles,
alternative formulations are compared, a variety of configurations
are addressed, the proper mathematical framework is discussed in
the context of functional analysis and integral-equation-theory,
and procedures of numerical solution in the context of the boundary
element method are introduced. The text contains a fair amount of
original material pertaining, in particular, to the properties and
explicit form of the Green's functions, and the theory of the
integral equations that arise from boundary integral
representations.
Originally published in 1926, this informative and detailed
textbook is primarily aimed at university students studying applied
mathematics for a science or engineering degree and contains a
large number of useful examples to work though. Basic knowledge of
elementary dynamics is assumed throughout, as is a working
knowledge of differential and integral calculus. Answers can be
found at the back of the book, as well as a summary of the methods
of solution of the equations contained. Examples are mostly
collected from a variety of past university and college examination
papers, and notably rigid dynamics has been confined to
two-dimensional motion and omissions have been made to all
reference of moving axes. Covering the topic in its entirety, this
book gives a panoramic overview of the subject and will be of
considerable value to anyone with a keen interest in mathematics
and engineering, as well as the history of education.
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