Study on Magnetohydrodynamic Turbulence and Its Astrophysical Applications

Study on Magnetohydrodynamic Turbulence and Its Astrophysical Applications

In closing, this book demonstrates the key role of MHD turbulence in connecting diverse astrophysical processes and unraveling long-standing astrophysical problems, as foreseen by Chandrasekhar, a founder of modern astrophysics.

Author: Siyao Xu

Publisher: Springer

ISBN: 9789811375156

Category: Science

Page: 157

View: 986

Turbulence and magnetic fields are ubiquitous in the Universe. Their importance to astronomy cannot be overestimated. The theoretical advancements in magnetohydrodynamic (MHD) turbulence achieved during the past two decades have significantly influenced many fields of astronomy. This book provides predictive theories of the magnetic field generation by turbulence and the dissipation of MHD turbulence. These fundamental non-linear problems were believed to be tractable only numerically. This book provides complete analytical descriptions in quantitative agreement with existing numerics, as well as theoretical predictions in physical regimes still unreachable by simulations, and explanations of various related observations. It also discusses and promotes the astrophysical applications of MHD turbulence theories, including (i) the particle acceleration and radiation in high-energy phenomena, e.g., Gamma-Ray Bursts, supernova remnants, cosmic rays; (ii) interstellar density fluctuations and the effect on observations, e.g., Faraday rotation, scattering measurements of Galactic and extragalactic radio sources; (iii) density and magnetic field structure in molecular clouds toward star formation. In closing, this book demonstrates the key role of MHD turbulence in connecting diverse astrophysical processes and unraveling long-standing astrophysical problems, as foreseen by Chandrasekhar, a founder of modern astrophysics.
Categories: Science

Broken Symmetry in Ideal Magnetohydrodynamic Turbulence

Broken Symmetry in Ideal Magnetohydrodynamic Turbulence

Author: John V. Shebalin

Publisher:

ISBN: NASA:31769000621113

Category:

Page: 17

View: 585

A numerical study of the long-time evolution of a number of cases of inviscid, isotropic, incompressible, three-dimensional fluid and magneto-fluid turbulence has been completed. The results confirm that ideal magnetohydrodynamic turbulence is non-ergodic if there is no external magnetic field present. This is due essentially to a canonical symmetry being broken in an arbitrary dynamical representation. The broken symmetry manifests itself as a coherent structure, i.e., a non-zero time-averaged part of the turbulent magnetic field. The coherent structure is observed, in one case, to contain about eighteen percent of the total energy. Isotropic turbulence, Ideal magnetohydrodynamics, Broken symmetry.
Categories:

Magnetohydrodynamic Turbulence

Magnetohydrodynamic Turbulence

... I. D. and Townsend, A. (1959). Small-scale variation of convected quantities
like temperature in a turbulent fluid. ... Dynamics and statistics in inverse cascade
processes in 2D magnetohydrodynamic turbulence, Phys. Rev. Lett. 72, 3469–72
.

Author: Dieter Biskamp

Publisher: Cambridge University Press

ISBN: 1139441671

Category: Science

Page:

View: 670

This book presents an introduction to, and modern account of, magnetohydrodynamic (MHD) turbulence, an active field both in general turbulence theory and in various areas of astrophysics. The book starts by introducing the MHD equations, certain useful approximations and the transition to turbulence. The second part of the book covers incompressible MHD turbulence, the macroscopic aspects connected with the different self-organization processes, the phenomenology of the turbulence spectra, two-point closure theory, and intermittency. The third considers two-dimensional turbulence and compressible (in particular, supersonic) turbulence. Because of the similarities in the theoretical approach, these chapters start with a brief account of the corresponding methods developed in hydrodynamic turbulence. The final part of the book is devoted to astrophysical applications: turbulence in the solar wind, in accretion disks, and in the interstellar medium. This book is suitable for graduate students and researchers working in turbulence theory, plasma physics and astrophysics.
Categories: Science

Surface Disturbances in Magnetohydrodynamics

Surface Disturbances in Magnetohydrodynamics

... of tangential disturbances is important for the development of a quantitative
explanation of the characteristics of magnetohydrodynamic turbulence .
Turbulent motion is developed as a result of instability of laminar flow of a liquid
or gas .

Author: Sergeĭ Ivanovich Syrovat͡skiĭ

Publisher:

ISBN: UIUC:30112106739839

Category: Magnetohydrodynamics

Page: 90

View: 998

Categories: Magnetohydrodynamics

Turbulence in Magnetohydrodynamics

Turbulence in Magnetohydrodynamics

[78] J. Cho, Simulations of relativistic force-free magnetohydrodynamic
turbulence, Astrophys.J. 621 (2005), 324–327. [79] J. Cho, Non-locality of
hydrodynamic and magnetohydrodynamic turbulence, Astrophys. J. 725 (2010),
1786–1791.

Author: Andrey Beresnyak

Publisher: Walter de Gruyter GmbH & Co KG

ISBN: 9783110263282

Category: Science

Page: 286

View: 600

Magnetohydrodynamics describes dynamics in electrically conductive fluids. These occur in our environment as well as in our atmosphere and magnetosphere, and play a role in the sun's interaction with our planet. In most cases these phenomena involve turbulences, and thus are very challenging to understand and calculate. A sound knowledge is needed to tackle these problems. This work gives the basic information on turbulence in nature, comtaining the needed equations, notions and numerical simulations. The current state of our knowledge and future implications of MHD turbulence are outlined systematically. It is indispensable for all scientists engaged in research of our atmosphere and in space science.
Categories: Science

NASA Thesaurus

NASA Thesaurus

MAGNEToHYDRODYNAMIC. STABILITY-(COWT). PLASMA EQUILIBRIUM
PLASMA LIFETIME PLASMA LOSS PLASMA PINCH PLASMA POTENTIALS
PLASMA SLABS PLASMA TEMPERATURE PLASMA TURBULENCE PLASMAS
 ...

Author:

Publisher:

ISBN: MINN:30000011024605

Category: Aeronautics

Page:

View: 165

Categories: Aeronautics

Large Eddy Simulations of Compressible Magnetohydrodynamic Turbulence

Large Eddy Simulations of Compressible Magnetohydrodynamic Turbulence

Supersonic, magnetohydrodynamic (MHD) turbulence is thought to play an important role in many processes - especially in astrophysics, where detailed three-dimensional observations are scarce.

Author: Philipp Grete

Publisher:

ISBN: OCLC:972382973

Category:

Page:

View: 100

Supersonic, magnetohydrodynamic (MHD) turbulence is thought to play an important role in many processes - especially in astrophysics, where detailed three-dimensional observations are scarce. Simulations can partially fill this gap and help to understand these processes. However, direct simulations with realistic parameters are often not feasible. Consequently, large eddy simulations (LES) have emerged as a viable alternative. In LES the overall complexity is reduced by simulating only large and intermediate scales directly. The smallest scales, usually referred to as subgrid-scales (SGS), ...
Categories:

Broken Symmetry in Ideal Magnetohydrodynamic Turbulence

Broken Symmetry in Ideal Magnetohydrodynamic Turbulence

The results confirm that ideal magnetohydrodynamic turbulence is non-ergodic if there is no external magnetic field present. This is due essentially to a canonical symmetry being broken in an arbitrary dynamical representation.

Author: National Aeronautics and Space Administration (NASA)

Publisher: Createspace Independent Publishing Platform

ISBN: 1725194759

Category:

Page: 38

View: 411

A numerical study of the long-time evolution of a number of cases of inviscid, isotropic, incompressible, three-dimensional fluid, and magneto-fluid turbulence has been completed. The results confirm that ideal magnetohydrodynamic turbulence is non-ergodic if there is no external magnetic field present. This is due essentially to a canonical symmetry being broken in an arbitrary dynamical representation. The broken symmetry manifests itself as a coherent structure, i.e., a non-zero time-averaged part of the turbulent magnetic field. The coherent structure is observed, in one case, to contain about eighteen percent of the total energy. Shebalin, John V. Unspecified Center NASA-TM-109017, ICASE-93-49, NAS 1.15:109017, AD-A272673 RTOP 505-90-52-01...
Categories:

Turbulence and Nonlinear Dynamics in MHD Flows

Turbulence and Nonlinear Dynamics in MHD Flows

Turbulence and Nonlinear Dynamics in MHD Flows M. Meneguzzi, A. Pquuet
and PL. Sulem (Editors) © Elsevier Science Publishers B.V. (North-Holland),
1989 ON THE ORIGIN OF SOLAR WIND TURBULENCE: HELIOS DATA
REVISITED ...

Author: M. Meneguzzi

Publisher: Elsevier

ISBN: 9780444598738

Category: Science

Page: 290

View: 459

Topics discussed at this international workshop include: magnetic fields in astrophysical flows, slow and fast dynamos, MHD turbulence in space plasmas and in the laboratory, exact solutions to MHD, topology and chaos in MHD, helicity and velocity-magnetic correlations, turbulent reconnection and non-magnetic flows.
Categories: Science

Nonlinear MHD Waves and Turbulence

Nonlinear MHD Waves and Turbulence

Recent developments in the derivation of reduced models for weakly
compressible magnetohydrodynamic (MHD) turbulence are discussed. A four-
field system of equations has been derived from the compressible
magnetohydrodynamic ...

Author: Thierry Passot

Publisher: Springer Science & Business Media

ISBN: 9783540666974

Category: Science

Page: 385

View: 664

The workshop "Nonhnear MHD Waves and Turbulence" was held at the - servatoire de Nice, December 1-4, 1998 and brought together an international group of experts in plasma physics, fluid dynamics and applied mathematics. The aim of the meeting was to survey the current knowledge on two main topics: (i) propagation of plasma waves (like Alfven, whistler or ion-acoustic waves), their instabilities and the development of a nonlinear dynamics lea ding to solitonic structures, wave collapse or weak turbulence; (ii) turbulence in magnetohydrodynamic flows and its reduced description in the presence of a strong ambient magnetic fleld. As is well known, both aspects play an important role in various geophysical or astrophysical media such as the - gnetospheres of planets, the heliosphere, the solar wind, the solar corona, the interplanetary and interstellar media, etc. This volume, which includes expanded versions of oral contributions pre sented at this meeting, should be of interest for a large community of resear chers in space plasmas and nonlinear sciences. Special effort was made to put the new results into perspective and to provide a detailed literature review. A main motivation was the attempt to relate more closely the theoretical un derstanding of MHD waves and turbulence (both weak and strong) with the most recent observations in space plasmas. Some papers also bring interesting new insights into the evolution of hydrodynamic or magnetohydrodynamic structures, based on systematic asymptotic methods.
Categories: Science

Nonlinear Processes in Geophysics

Nonlinear Processes in Geophysics

Three key issues are identified regarding the use of Hall MHD to describe
turbulence in kinetic plasmas : ( 1 ) what are the wave modes comprising the
turbulence at scales kd ; > 1 ?; ( 2 ) are the collisionless damping rates from
linear kinetic ...

Author:

Publisher:

ISBN: UCSD:31822031460157

Category: Geophysics

Page:

View: 509

Categories: Geophysics

Advances in Turbulence 7

Advances in Turbulence 7

Shebalin , J . V . , Matthaeus , W . H . & Montgomery , D . ( 1983 ) Anisotropy in
MHD turbulence due to a mean magnetic ... of shear - Alfvén wave packets :
Implications for weak magnetohydrodynamic turbulence in astrophysical plasmas
.

Author: Uriel Frisch

Publisher: Springer Science & Business Media

ISBN: STANFORD:36105023056927

Category: Science

Page: 613

View: 471

This volume contains an overview of the state of turbulence research with some bias towards work done in Europe. It represents an almost complete collection of the invited and contributed papers delivered at the Seventh European Turbulence Conference, sponsored by EUROMECH and ERCOFTAC and organized by the Observatoire de la Cote d'Azur. High-Reynolds number experiments combined with techniques of imaging, non-intrusive probing, processing and simulation provide high-quality data which put significant constraints on possible theories. For the first time, it has been shown, for a class of passive scalar problems, why dimensional analysis sometimes gives the wrong answers and how anomalous intermittency corrections can be calculated from first principles. The volume is thus geared towards specialists in the area of flow turbulence who could not attend the conference as well as anybody interested in this rapidly-moving field.
Categories: Science

Magnetic Helicity in Space and Laboratory Plasmas

Magnetic Helicity in Space and Laboratory Plasmas

Montgomery, D., L. Turner, and G. Vahala, Three dimensional
magnetohydrodynamic turbulence in cylindrical geometry, Phys. Fluids 21, 757-
764, 1978. Montgomery, D., and L. Phillips, Minimum dissipation rates in
magnetohydrodynamics, ...

Author: Michael R. Brown

Publisher: American Geophysical Union

ISBN: UCSD:31822027770403

Category: Science

Page: 304

View: 533

Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 111. Using the concept of magnetic helicity, physicists and mathematicians describe the topology of magnetic fields: twisting, writhing, and linkage. Mathematically, helicity is related to linking integrals, which Gauss introduced in the 19th century to describe the paths of asteroids in the sky. In the late 1970s the concept proved to be critical to understand laboratory plasma experiments on magnetic reconnection, dynamos, and magnetic field relaxation. In the late 1980s it proved equally important in understanding turbulence in the solar wind and the interplanetary magnetic field. During the last five years interest in magnetic helicity has grown dramatically in solar physics, and it will continue to grow as observations of vector magnetic fields become increasingly sophisticated.
Categories: Science

Magnetohydrodynamics

Magnetohydrodynamics

The conflicting results achieved using different expansion methods led us to a
speculative deduction that the double expansion applied here is physically close
to the description of quasi - two - dimensional ( 2 < d < 3 ) turbulent flows .

Author:

Publisher:

ISBN: UCSD:31822022679690

Category:

Page:

View: 153

Categories:

International Aerospace Abstracts

International Aerospace Abstracts

... developed magnetohydrodynamic turbulence ( c75 A95 - 16545 ) Convective -
type instabilities in developed small - scale magnetohydrodynamic turbulence (
c75 A95 - 16549 ) Modified adiabatic approximation for a hydrogen atom moving
 ...

Author:

Publisher:

ISBN: UOM:39015030228251

Category: Aeronautics

Page:

View: 328

Categories: Aeronautics

Lecture Notes on Turbulence

Lecture Notes on Turbulence

MAGNETOHYDRODYNAMIC TURBULENCE Preface Magnetohydrodynamic (
MHD ) turbulence is more difficult to present in lectures than fluid turbulence is ,
for several reasons : ( 1 ) less is known about it , theoretically and experimentally
 ...

Author: Jackson R. Herring

Publisher: World Scientific

ISBN: 9971508273

Category: Science

Page: 371

View: 830

This book is a formal presentation of lectures given at the 1987 Summer School on Turbulence, held at the National Center for Atmospheric Research under the auspices of the Geophysical Turbulence Program. The lectures present in detail certain of the more challenging and interesting current turbulence research problems in engineering, meteorology, plasma physics, and mathematics. The lecturers-Uriel Frisch (Mathematics), Douglas Lilly (Meteorology), David Montgomery (Plasma Physics), and Hendrik Tennekes (Engineering) ? are distinguished for both their research contributions and their abilities to communicate these to students with enthusiasm. This book is distinguished by its simultaneous focus on the fundamentals of turbulent flows (in neutral and ionized fluids) and on a presentation of current research tools and topics in these fields.
Categories: Science

Proceedings of the Mini workshop on Physical Processes in the Solar Transition region and Corona Institute of Theoretical Astrophysics University of Oslo 18 20 June 1990

Proceedings of the Mini workshop on Physical Processes in the Solar Transition region and Corona  Institute of Theoretical Astrophysics  University of Oslo  18 20 June 1990

Marsch , E. , MHD Turbulence in the Solar Wind , in Physics of the Inner
Heliosphere , Vol . II , ed . by R. Schwenn and E. Marsch , Springer - Verlag ,
Heidelberg , in press , 1990a . Marsch , E. , Kinetic physics of the solar wind
plasma , in ...

Author: P. Maltby

Publisher:

ISBN: CHI:82081321

Category: Solar atmosphere

Page: 199

View: 932

Categories: Solar atmosphere

Progress in Turbulence Research

Progress in Turbulence Research

Developed. Magnetohydrodynamic. Turbulence. Nathan Kleeorin* Ben-Gurion
University of the Negev, Beer-Sheva, Israel ... of mean magnetic force caused by
a developed small-scale magnetohydrodynamic (MHD) turbulence is considered.

Author: Herman Branover

Publisher: AIAA

ISBN: 1600864155

Category: Turbulence

Page: 348

View: 163

Categories: Turbulence

Journal of the Physical Society of Japan

Journal of the Physical Society of Japan

... Physical Society of Japan Simulation Study of Energy Conversion Process in
Magnetohydrodynamic Turbulence Due ... and the dynamo action in the
magnetohydrodynamic ( MHD ) turbulence due to the magnetorotational
instability ( MRI ) ...

Author:

Publisher:

ISBN: OSU:32435075516666

Category: Physics

Page:

View: 769

Categories: Physics