Fluid Mechanics Of Planets And Stars

This book explores the dynamics of planetary and stellar fluid layers, including atmospheres, oceans, iron cores, and convective and radiative zones in stars, describing the different theoretical, computational and experimental methods used to study these problems in fluid mechanics, including the advantages and limitations of each method for different problems. This scientific domain is by nature interdisciplinary and multi-method, but while much effort has been devoted to solving open questions within the various fields of mechanics, applied mathematics, physics, earth sciences and astrophysics, and while much progress has been made within each domain using theoretical, numerical and experimental approaches, cross-fertilizations have remained marginal. Going beyond the state of the art, the book provides readers with a global introduction and an up-to-date overview of relevant studies, fully addressing the wide range of disciplines and methods involved. The content builds on the CISM course “Fluid mechanics of planets and stars”, held in April 2018, which was part of the research project FLUDYCO, supported by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program.

This book grew out of the need to provide students with a solid introduction to modern fluid dynamics. It offers a broad grounding in the underlying principles and techniques used, with some emphasis on applications in astrophysics and planetary science. The book comprehensively covers recent developments, methods and techniques, including, for example, new ideas on transitions to turbulence (via transiently growing stable linear modes), new approaches to turbulence (which remains the enigma of fluid dynamics), and the use of asymptotic approximation methods, which can give analytical or semi-analytical results and complement fully numerical treatments. The authors also briefly discuss some important considerations to be taken into account when developing a numerical code for computer simulation of fluid flows. Although the text is populated throughout with examples and problems from the field of astrophysics and planetary science, the text is eminently suitable as a general introduction to fluid dynamics. It is assumed that the readers are mathematically equipped with a reasonable knowledge in analysis, including basics of ordinary and partial differential equations and a good command of vector calculus and linear algebra. Each chapter concludes with bibliographical notes in which the authors briefly discuss the chapter's essential literature and give recommendations for further, deeper reading. Included in each chapter are a number of problems, some of them relevant to astrophysics and planetary science. The book is written for advanced undergraduate and graduate students, but will also prove a valuable source of reference for established researchers.

Cosmology, astronomy and astrophysics modified by application of modern fluid mechanics, turbulence, turbulent mixing, fossil turbulence, fossil turbulent waves and turbulent transport processes in the ocean, atmosphere, stars and other objects composed of natural fluids. New cosmology replaces the standard model of old cosmology, and renders concepts of cold dark matter and dark energy obsolete. Galaxy dark matter consists of frozen gas primordial Earth-mass planets in dense clumps with enough planets to make a million stars. All stars form in the clumps by planet mergers. Stars such as the sun die by overeating the planets until they explode to form stardust that is collected and processed by the planets to form life. Thirty million planets exist per star in a galaxy.

This first course in fluid dynamics covers the basics and introduces a wealth of astronomical applications.

In all phases of the life of a star, hydrodynamical processes play a major role. This volume gives a comprehensive overview of the state of knowledge in stellar astrophysical fluid dynamics, and its publication marked the 60th birthday of Douglas Gough, Professor of Theoretical Physics at the University of Cambridge and leading contributor to stellar astrophysical fluid dynamics. Topics include properties of pulsating stars, helioseismology, convection and mixing in stellar interiors, dynamics of stellar rotation, planet formation and the generation of stellar and planetary magnetic fields. Each chapter is written by leading experts in the field, and the book provides an overview that is central to any attempt to understand the properties of stars and their evolution. With extensive references to the technical literature, this is a valuable text for researchers and graduate students in stellar astrophysics.

This textbook is a general introduction to the dynamics of astrophysical fluids for students with a knowledge of basic physics at the undergraduate level. No previous knowledge of fluid dynamics or astrophysics is required because the author develops all new concepts in context. The first four chapters cover classical fluids, relativistic fluids, photon fluids and plasma fluids, with many cosmic examples being included. The remaining six chapters deal with astrophysical applications: stars, stellar systems, astrophysical plasmas, cosmological applications, and large scale structure of the universe. Astrophysical fluid dynamics is a promising branch of astronomy, with wide applicability. This textbook considers the role of plasma and magnetism in planets, stars, galaxies, the interplanetary, interstellar and intergalactic media, as well as the universe at large.

The increasing power of computer resources along with great improvements in observational data in recent years have led to some remarkable and rapid advances in astrophysical fluid dynamics. The subject spans three distinct but overlapping communities whose interests focus on (1) accretion discs and high-energy astrophysics; (2) solar, stellar, and galactic magnetic fields; and (3) the geodynamo, planetary magnetic fields, and associated experiments. This book grew out of a special conference sponsored by the London Mathematical Society with the support of EPSRC that brought together leading researchers in all of these areas to exchange ideas and review the status of the field. The many interesting problems addressed in this volume concern:

This book is dedicated to readers who want to learn fluid dynamics from the beginning. It assumes a basic level of mathematics knowledge that would correspond to that of most second-year undergraduate physics students and examines fluid dynamics from a physicist’s perspective. As such, the examples used primarily come from our environment on Earth and, where possible, from astrophysics. The text is arranged in a progressive and educational format, aimed at leading readers from the simplest basics to more complex matters like turbulence and magnetohydrodynamics. Exercises at the end of each chapter help readers to test their understanding of the subject (solutions are provided at the end of the book), and a special chapter is devoted to introducing selected aspects of mathematics that beginners may not be familiar with, so as to make the book self-contained.

Fluid dynamical forces drive most of the fundamental processes in the Universe and so play a crucial role in our understanding of astrophysics. This comprehensive textbook, first published in 2007, introduces the necessary fluid dynamics to understand a wide range of astronomical phenomena, from stellar structures to supernovae blast waves, to accretion discs. The authors' approach is to introduce and derive the fundamental equations, supplemented by text that conveys a more intuitive understanding of the subject, and to emphasise the observable phenomena that rely on fluid dynamical processes. The textbook has been developed for use by final-year undergraduate and starting graduate students of astrophysics, and contains over fifty exercises. It is based on the authors' many years of teaching their astrophysical fluid dynamics course at the University of Cambridge.

Cosmology, astronomy and astrophysics modified by application of modern fluid mechanics, turbulence, turbulent mixing, fossil turbulence, fossil turbulent waves and turbulent transport processes in the ocean, atmosphere, stars and other objects composed of natural fluids. New cosmology renders concepts of cold dark matter and dark energy obsolete. Galaxy dark matter consists of frozen gas primordial Earth-mass planets in dense clumps with enough planets to make a million stars. All stars form by planet mergers. Stars such as the sun die by overeating the planets until they explode to form stardust that is collected and processed by the planets to form life. The cover image shows the Stephan Quintet compact group of galaxies end on and stretching. New Cosmology predicts galaxies form by fragmentation along vortex lines of turbulence in the plasma soon before transition to gas at 0.002% of the age of the universe since the big bang (13.7 Gyr).