Download or read book Plasma Transport in Stochastic Magnetic Fields III written by John A. Krommes and published by . This book was released on 1982 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasma Transport in Stochastic Magnetic Fields III Kinetics of Test particle Diffusion written by and published by . This book was released on 1982 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A discussion is given of test particle transport in the presence of specified stochastic magnetic fields, with particular emphasis on the collisional limit. Certain paradoxes and inconsistencies in the literature regarding the form of the scaling laws are resolved by carefully distinguishing a number of physically distinct correlation lengths, and thus by identifying several collisional subregimes. The common procedure of averaging the conventional fluid equations over the statistics of a random field is shown to fail in some important cases because of breakdown of the Chapman-Enskog ordering in the presence of a stochastic field component with short autocorrelation length. A modified perturbation theory is introduced which leads to a Kubo-like formula valid in all collisionality regimes. The direct-interaction approximation is shown to fail in the interesting limit in which the orbit exponentiation length L/sub K/ appears explicitly. A higher order renormalized kinetic theory in which L/sub K/ appears naturally is discussed and used to rederive more systematically the results of the heuristic scaling arguments.

Download or read book Plasma Transport in Stochastic Magnetic Fields II written by John A. Krommes and published by . This book was released on 1978 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasma Transport in Stochastic Magnetic Fields I written by John A. Krommes and published by . This book was released on 1978 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasma Transport in Stochastic Magnetic Fields II Principles and Problems of Test Electron Transport written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A model stochastic differential equation is considered which describes guiding center electron motion in a statistically specified spectrum of turbulent magnetic fluctuations. The fluctuation intensity is assumed to satisfy the Chirikov criterion (resonance overlap) for onset of stochasticity. In this limit typical lines diffuse and are adequately described by a quasilinear diffusion coefficient D/sub m/. However, quasilinear theory does not describe an important mechanism for loss of particle correlations: particles collisionally diffuse from one line to an adjacent one which diverges rapidly from the first, carrying the particles away. The scale length L/sub K/ for line divergence is related to the inverse of the Kolmogorov-Sinai entropy. An attempt is made to determine L/sub K/ from a simplified Eulerian vertex renormalization. The exponentiation length which emerges is L/sub K/ approximately L/sub s/(anti k2/sub theta/D''/sub m/L/sub s/)−13, where L/sub s/ is the shear length, k bar/sub theta/ is a typical azimuthal wavenumber, and D''/sub m/ is of order D/sub m/. In a particular limit of weak shear, the particle diffusion coefficient can then be estimated as D approximately DELTA r2?sub c/, where .delta.r2 approximately D/sub m/z(tau/sub c/), z? is the distance traveled along the lines in time tau, and for static fluctuations tau/sub c/ approximately tau(L/sub delta/), where L/sub delta/ is L/sub K/ multiplied by a logarithmic factor involving the perpendicular collisional diffusion coefficient.

Download or read book Plasma Transport in Stochastic Magnetic Field Caused by Vacuum Resonant Magnetic Perturbations at Diverted Tokamak Edge written by and published by . This book was released on 2010 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasma Transport in Stochastic Magnetic Fields I General Considerations and Test Particle Transport written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A systematic theory is developed for the computation of electron transport in stochastic magnetic fields. Small scale magnetic perturbations arising, for example, from finite-.beta. micro-instabilities are assumed to destroy the flux surfaces of a standard tokamak equilibrium. Because the magnetic lines then wander in a volume, electron radial flux is enhanced due to the rapid particle transport along as well as across the lines. By treating the magnetic lines as random variables, it is possible to develop a kinetic equation for the electron distribution function. This is solved approximately to yield the diffusion coefficient.

Download or read book Transport in a Stochastic Magnetic Field written by Jean-Marcel Rax and published by . This book was released on 1992 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Turbulent Transport In Magnetized Plasmas Second Edition written by C Wendell Horton, Jr and published by #N/A. This book was released on 2017-07-21 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt: For a few seconds with large machines, scientists and engineers have now created the fusion power of the stars in the laboratory and at the same time find the rich range of complex turbulent electromagnetic waves that transport the plasma confinement systems. The turbulent transport mechanisms created in the laboratory are explained in detail in the second edition of 'Turbulent Transport in Magnetized Plasmas' by Professor Horton.The principles and properties of the major plasma confinement machines are explored with basic physics to the extent currently understood. For the observational laws that are not understood — the empirical confinement laws — offering challenges to the next generation of plasma students and researchers — are explained in detail. An example, is the confinement regime — called the 'I-mode' — currently a hot topic — is explored.Numerous important problems and puzzles for the next generation of plasma scientists are explained. There is growing demand for new simulation codes utilizing the massively parallel computers with MPI and GPU methods. When the 20 billion dollar ITER machine is tested in the 2020ies, new theories and faster/smarter computer simulations running in near real-time control systems will be used to control the burning hydrogen plasmas.

Download or read book Magnetic Stochasticity in Magnetically Confined Fusion Plasmas written by Sadrilla Abdullaev and published by Springer Science & Business Media. This book was released on 2013-11-19 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first book to systematically consider the modern aspects of chaotic dynamics of magnetic field lines and charged particles in magnetically confined fusion plasmas. The analytical models describing the generic features of equilibrium magnetic fields and magnetic perturbations in modern fusion devices are presented. It describes mathematical and physical aspects of onset of chaos, generic properties of the structure of stochastic magnetic fields, transport of charged particles in tokamaks induced by magnetic perturbations, new aspects of particle turbulent transport, etc. The presentation is based on the classical and new unique mathematical tools of Hamiltonian dynamics, like the action--angle formalism, classical perturbation theory, canonical transformations of variables, symplectic mappings, the Poincaré-Melnikov integrals. They are extensively used for analytical studies as well as for numerical simulations of magnetic field lines, particle dynamics, their spatial structures and statistical properties. The numerous references to articles on the latest development in the area are provided. The book is intended for graduate students and researchers who interested in the modern problems of magnetic stochasticity in magnetically confined fusion plasmas. It is also useful for physicists and mathematicians interested in new methods of Hamiltonian dynamics and their applications.

Download or read book Collisionless Transport in a Stochastic Magnetic Field written by R. B. White and published by . This book was released on 1992 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aspects of Anomalous Transport in Plasmas written by Radu Balescu and published by CRC Press. This book was released on 2005-04-01 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anomalous transport is a ubiquitous phenomenon in astrophysical, geophysical and laboratory plasmas; and is a key topic in controlled nuclear fusion research. Despite its fundamental importance and ongoing research interest, a full understanding of anomalous transport in plasmas is still incomplete, due to the complexity of the nonlinear phenomena involved. Aspects in Anomalous Transport in Plasmas is the first book to systematically consider anomalous plasma transport theory and provides a unification of the many theoretical models by emphasizing interrelations between seemingly different methodologies. It is not intended as a catalogue of the vast number of plasma instabilities leading to anomalous transport; instead it chooses a number of these and emphasizes the aspects specifically due to turbulence. After a brief introduction, the microscopic theory of turbulence is discussed, including quasilinear theory and various aspects of renormalization methods, which leads to an understanding of resonance broadening, mode coupling, trajectory correlation and clumps. The second half of the book is devoted to stochiastic tramsport, using methods based on the Langevin equations and on Random Walk theory. This treatment aims at going beyond the traditional limits of weak turbulence, by introducing the recently developed method of decorrelation trajectories, and its application to electrostatic turbulence, magnetic turbulence and zonal flow generation. The final chapter includes very recent work on the nonlocal transport phenomenon.

Download or read book Nonlocal Heat Transport in a Stochastic Magnetic Field written by Jean-Marcel Rax and published by . This book was released on 1991 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1978 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Transport Phenomena in Stochastic Magnetic Mirrors written by Leonid M. Malyshkin and published by . This book was released on 2000 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasma Transport in Mixed Magnetic Topologies written by and published by . This book was released on 1992 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: A simple model is introduced to illustrate some features concerning anomalous transport associated with magnetic turbulence. For magnetic topologies that are described as bands of stochasticity separated by regions with good flux surfaces, the transport coefficients deviate significantly from those describing completely stochastic magnetic fields. It is possible to have the electron heat diffusivity exceed a runaway electron diffusion coefficient, despite the existence of widespread magnetic stochasticity. Comparing the ratios of transport coefficients is not an accurate way to determine whether anomalous plasma transport is controlled by electrostatic or electromagnetic fluctuations.