Author: Philippe Ghendrih
Publisher: World Scientific
ISBN: 9814644846
Category : Science
Languages : en
Pages : 336
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Book Description
This book compiles the contributions from various international experts on magnetized plasma physics, both in controlled fusion and in astrophysics, and on atmospheric science. Most recent results are presented along with new ideas. The various facets of rotation and momentum transport in complex systems are discussed, including atmospheric-ocean turbulence, the constraints, and the concept of potential vorticity. The close interplay between flows and magnetohydrodynamics dynamo action, instabilities, turbulence and structure dynamics are the main focus of the book, in the context of astrophysics and magnetic fusion devices like Tokamak, and Reversed Field Pinch. Both physicists and advanced students interested in the field will find the topics as interesting as researchers from other fields who are looking to broaden their perspectives.
Author: John Rice
Publisher: Springer Nature
ISBN: 3030922669
Category : Science
Languages : en
Pages : 158
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Book Description
This book provides a comprehensive look at the state of the art of externally driven and self-generated rotation as well as momentum transport in tokamak plasmas. In addition to recent developments, the book includes a review of rotation measurement techniques, measurements of directly and indirectly driven rotation, momentum sinks, self-generated flow, and momentum transport. These results are presented alongside summaries of prevailing theory and are compared to predictions, bringing together both experimental and theoretical perspectives for a broad look at the field. Both researchers and graduate students in the field of plasma physics will find this book to be a useful reference. Although there is an emphasis on tokamaks, a number of the concepts are also relevant to other configurations.
Author: Steven Mark Crooks
Publisher:
ISBN:
Category :
Languages : en
Pages : 246
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Book Description
Author: Horton, Jr C Wendell
Publisher: #N/A
ISBN: 9813225904
Category : Science
Languages : en
Pages : 524
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Book Description
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.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 1
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Book Description
This report covers the UW-Madison activities that took place within a larger DoE Center Administered and directed by Professor George Tynan at the University of California, San Diego. The work at Wisconsin will also be covered in the final reporting for the entire center, which will be submitted by UCSD. There were two main activities, one experimental and one that was theoretical in nature, as part of the Center activities at the University of Wisconsin, Madison. First, the Center supported a experimentally focused postdoc (Chris Cooper) to carry out fundamental studies of momentum transport in rotating and weakly magnetized plasma. His experimental work was done on the Plasma Couette Experiment, a cylindrical plasma confinement device, with a plasma flow created through electromagnetically stirring plasma at the plasma edge facilitated by arrays of permanent magnets. Coopers work involved developing optical techniques to measure the ion temperature and plasma flow through Doppler shifted line radiation from the plasma Argon ions. This included passive emission measurements and development of a novel ring summing Fabry-Perot spectroscopy system, and the active system involved using a diode laser to induce fluorescence. On the theoretical side, CMTFO supported a postdoc (Johannes Pueschel) to carry out a gyrokinetic extension of resisdual zonal flow theory to the case with magnetic fluctuations, showing that magnetic stochasticity disrupts zonal flows. The work included a successful comparison with gyrokinetic simulations. This work and its connection to the broader CMTFOwill be covered more thoroughly in the final CMTFO report from Professor Tynan.
Author: Ian Emanuel Ochs
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
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Book Description
This dissertation focuses on two related topics: controlling plasma rotation, and extracting ash from fusion reactors. Rotation is an extremely useful tool in plasma control, allowing for instability suppression, enhanced confinement, and the separation of different species. Ash, meanwhile, is a hot, charged byproduct of the fusion reaction that tends to heat electrons, degrading confinement and radiating away energy. Alpha channeling rectifies this situation by transferring the ash energy into a useful wave, while simultaneously extracting the ash from the plasma.It has been proposed that alpha channeling also extracts net charge from the plasma, generating an electric field and thus E x B rotation. However, existing theories do not explain how this process would conserve momentum.To develop a consistent theory, we first examine collisional transport in a magnetized plasma to review the deep connection between charge transport and momentum conservation. We then use this intuition to guide the development of a self-consistent, momentum-conserving theory of alpha channeling. We find an important difference between plane waves which grow in time, which do not drive rotation, and spatially structured waves, which do. This theory definitively determines the conditions under which alpha channeling extracts charge, within a very simple mathematical framework.Our models have many applications. We explore how E x B rotation can be used in toroidal systems to provide a self-consistent rotational transform, or in open-field-line geometries to centrifuge and remediate nuclear waste. We also show how waves can mediate collisionless momentum exchange between plasma constituents, and thus generate currents and magnetic fields in astrophysical systems.The techniques we develop turn out to also have immediate application to inertial confinement systems. We uncover surprising effects in Z-pinches, showing how magneto-inertial fusion reactors can be made more reactive than previously thought by leveraging multi-ion transport effects that naturally flush out ash. We also explain unintuitive rotation and current redistribution effects in existing Z-pinch experiments.Despite our application to very different plasma systems, occurring in apparently far-flung regimes of plasma physics, the same themes and models emerge repeatedly. Recognizing these deep connections reveals new opportunities for improving plasma control.
Author: Pierre Cottier
Publisher: LAP Lambert Academic Publishing
ISBN: 9783659411038
Category :
Languages : en
Pages : 128
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Book Description
The magnetic confinement in tokamaks is for now the most advanced way towards energy production by nuclear fusion. Both theoretical and experimental studies showed that rotation generation can increase its performance by reducing the turbulent transport in tokamak plasmas. The rotation influence on the heat and particle fluxes is studied along with the angular momentum transport with the quasi-linear gyro-kinetic eigenvalue code QuaLiKiz. For this purpose, the QuaLiKiz code is modified in order to take the plasma rotation into account and compute the angular momentum flux. It is shown that QuaLiKiz framework is able to correctly predict the angular momentum flux including the ExB shear induced residual stress as well as the influence of rotation on the heat and particle fluxes. The different contributions to the turbulent momentum flux are studied and successfully compared against both non-linear gyro-kinetic simulations and experimental data.
Author: Per Helander
Publisher: Cambridge University Press
ISBN: 9780521020985
Category : Science
Languages : en
Pages : 316
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Book Description
A graduate level text treating transport theory, an essential element of theoretical plasma physics.
Author: Jesse Ethan Pino
Publisher:
ISBN:
Category : Accretion (Astrophysics)
Languages : en
Pages : 224
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Book Description
The Magnetorotational Instability (MRI) is believed to be the primary mechanism for angular momentum transfer in astrophysical accretion disks. This instability, which exists in ionized disks in the presence of weak magnetic fields, can either transfer angular momentum directly, or give rise to anomalous viscosity via non-linear turbulence. While many previous analytical treatments are concerned with the local theory of the MRI, when the length scale of rotation shear is comparable to the length scale of the most unstable modes, a global analysis is necessary. In this dissertation we investigate the global theory of the linear MRI. In particular, we show how rotation shear can localize global modes and how the global growth rates can differ signicantly from the local approximation in certain cases. Changes in the equilibrium density are considered. In addition, the effects of Hall Magnetohydrodynamics on the MRI are studied in both the local and global cases.
Author: Jason Michael Kriesel
Publisher:
ISBN:
Category :
Languages : en
Pages : 424
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Book Description
