Long-wavelength Microinstabilities in Toroidal Plasmas PDF Download

Author: G. Rewoldt
Publisher:
ISBN:
Category : Drift waves
Languages : en
Pages : 27

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Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 28

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Book Description
Realistic kinetic toroidal eigenmode calculations have been carried out to support a proper assessment of the influence of long-wavelength microturbulence on transport in tokamak plasmas. In order to efficiently evaluate large-scale kinetic behavior extending over many rational surfaces, significant improvements have been made to a toroidal finite element code used to analyze the fully two-dimensional (r, [theta]) mode structures of trapped-ion and toroidal ion temperature gradient (ITG) instabilities. It is found that even at very long wavelengths, these eigenmodes exhibit a strong ballooning character with the associated radial structure relatively insensitive to ion Landau damping at the rational surfaces. In contrast to the long-accepted picture that the radial extent of trapped-ion instabilities is characterized by the ion-gyroradius-scale associated with strong localization between adjacent rational surfaces, present results demonstrate that under realistic conditions, the actual scale is governed by the large-scale variations in the equilibrium gradients. Applications to recent measurements of fluctuation properties in TFTR L-mode plasmas indicate that the theoretical trends appear consistent with spectral characteristics as well as rough heuristic estimates of the transport level. Benchmarking calculations in support of the development of a three-dimensional toroidal gyrokinetic code indicate reasonable agreement with respect to both the properties of the eigenfunctions and the magnitude of the eigenvalues during the linear phase of the simulations of toroidal ITG instabilities.

Author: Taik Soo Hahm
Publisher:
ISBN:
Category : Computer simulation
Languages : en
Pages : 7

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Author: Wallace M. Manheimer
Publisher: CRC Press
ISBN:
Category : Art
Languages : en
Pages : 312

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Magnetohydrodynamics, the study of the motion of electrically conducting fluids in magnetic fields, is an important area in plasma physics. The effects of instabilities in such electrical fluids are very difficult to calculate and this is the first book to deal with the subject as a whole in a detailed manner. MHD and Microinstabilities in Confined Plasma starts from first principles and builds up to a full understanding of MHD. It features a number of topics not covered in other books on plasma, including non-linear theory, anomalous transport and magnetic reconnection.

Author: Ferdinand F. Cap
Publisher: Academic Press
ISBN: 148327098X
Category : Science
Languages : en
Pages : 575

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Handbook on Plasma Instabilities, Volume 2 consists of four chapters on plasma instabilities. Chapter 14 discusses the various aspects of microinstabilities. Beam-plasma systems are covered in Chapter 15, while the various stabilization methods are presented in Chapter 16. This book concludes with deliberations on parametric effects in Chapter 17. Other topics discussed include the microinstabilities of a homogeneous unmagnetized plasma; kinetic theory of macroscopic instabilities; basic beam physics; and beam-plasma instabilities. The magnetic field configuration stabilization; macroscopic nonmagnetic stabilization methods; parametric instabilities in homogeneous unmagnetized plasmas; and parametric effects in bounded and inhomogeneous plasmas are also elaborated in this text. This publication is beneficial to students and researchers conducting work on unstable plasma.

Author:
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ISBN:
Category :
Languages : en
Pages : 7

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Fluctuating bootstrap currents provide a mechanism for long wavelength electromagnetic fluctuations in tokamak plasmas. The existence of micro-magnetic islands may be responsible for the experimental observations of core density fluctuations. A fluctuation model is introduced for the tokamak that describes the magnetic topology as a time-varying mix of magnetic islands, stochastic zones and good'' magnetic surfaces.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 12

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This report discusses long-wavelength microinstabilities in toroidal plasmas and alpha particle destabilization of TAE modes in TFTR DT Experiments.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 8

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A comprehensive program for the development and use of particle simulation techniques for solving the gyrokinetic Vlasov-Maxwell equations on massively parallel computers has been carried out at Princeton Plasma Physics Laboratory. This is a key element of our ongoing theoretical efforts to systematically investigate physics issues vital to understanding tokamak plasmas. In this paper, our focus is on spatial-gradient-driven microinstabilities. Their importance is supported by the recent progress in achieving a physics-based understanding of anomalous transport in toroidal systems which has been based on the proposition that these drift-type electrostatic modes dependent on ion temperature gradient (ITG) and trapped particle effects are dominant in the bulk (''confinement'') region. Although their presence is consistent with a number of significant confinement trends, results from high temperature tokamaks such as TFTR have highlighted the need for better insight into the nonlinear properties of such instabilities in long-mean-free-path plasmas. In addressing this general issue, we report important new results including (i) the first fully toroidal 3D gyrokinetic simulation of ITG modes and (ii) realistic toroidal eigenmode calculations demonstrating the unique capability to deal with large scale kinetic behavior extending over many rational surfaces. The effects of ITG modes (iii) on the inward pinch of impurities in 3D slab geometry and (iv) on the existence of microtearing modes in 2D slab are also discussed. Finally, (v) sheared toroidal flow effects on trapped-particle modes are presented.

Author:
Publisher:
ISBN:
Category : Nuclear energy
Languages : en
Pages : 912

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Author: MITSURU KIKUCHI
Publisher: International Atomic Energy
ISBN:
Category : Antiques & Collectibles
Languages : en
Pages : 1158

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