Download or read book Tearing Mode Analysis in Tokamaks Revisited written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A new[Delta][prime] shooting code has been developed to investigate tokamak plasma tearing mode stability in a cylinder and large aspect ratio ([epsilon][le] 0.25) toroidal geometries, neglecting toroidal mode coupling. A different computational algorithm is used (shooting out from the singular surface instead of into it) to resolve the strong singularities at the mode rational surface, particularly in the presence of finite pressure term. Numerical results compare favorably with Furth et al. results. The effects of finite pressure, which are shown to decrease[Delta][prime], are discussed. It is shown that the distortion of the flux surfaces by the Shafranov shift, which modifies the geometry metric element stabilizes the tearing mode significantly, even in a low[beta] regime before the toroidal magnetic curvature effects come into play. Double tearing modes in toroidal geometries are examined as well. Furthermore, m[ge] 2 tearing mode stability criteria are compared with three dimensional initial value MHD simulation by the FAR code.

Download or read book Tearing Mode Dynamics in Tokamak Plasmas written by Richard Fitzpatrick and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of humankind's ultimate energy source, nuclear fusion, has proceeded slowly but surely over the course of the last 60 years. This comprehensive book aims to outline a realistic, comprehensive, self-consistent, analytic theory of tearing mode dynamics in tokamak plasmas. It discusses a fluid theory of a highly magnetized plasma that treats the electrons and ions as independent fluids, and then proceeds to develop the theory of tearing modes, first approximating the geometry of a tokamak plasma as a periodic cylinder, but eventually considering the toroidal structure of real tokamak plasmas. This book also describes the stability of tearing modes, the saturation of such modes, and the evolution of their phase velocity due to interaction with other tearing modes, as well as the resistive vacuum vessel, and imperfections in the tokamak's magnetic field. This text will appeal to scientists and graduate students engaged in nuclear fusion research, and would make a useful reference for graduate plasma physics courses. Part of IOP Series in Plasma Physics.

Download or read book Tearing Mode Dynamics in Tokamak Plasmas written by Nikolaos Vergos and published by . This book was released on 2016 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most problematic instabilities in tokamak plasmas is tearing modes; they are driven by current and pressure gradients, and involve a reconfiguration of the magnetic and velocity fields localized into a narrow region located at a resonant magnetic surface. While the equilibrium magnetic field lines are located on concentric nested toroidal flux surfaces, the instability creates magnetic islands in which field lines connect flux tubes together, allowing for a high radial heat transport, and, thus, resulting in a loss of confinement, and, potentially, disruptions. In order for the magnetic field lines to break and reconnect, we need to take into account the resistivity of the plasma and solve the resistive magnetohydrodynamics (MHD) equations. The analytical solution consists of a boundary layer analysis (asymptotic matching) and takes advantage of the small radial width of the region where the perturbations vary significantly. Indeed, ideal magnetohydrodynamics can be used everywhere except in that narrow region where the full resistive problem must be solved. This dissertation addresses two related problems in the study of resistive tearing modes, and their interactions with externally induced resonant magnetic perturbations (error-fields). First, an in-depth investigation of the bifurcated states of a rotating, quasi-cylindrical, tokamak plasma in the presence of a resonant error-field is performed, within the context of constant-[greek letter psi] resistive MHD theory. The response of the rotating plasma is studied in both the linear, and the nonlinear regime. In general, there is a "forbidden band" of tearing mode rotation frequencies that separates a branch of high-frequency solutions from a branch of low-frequency solutions. When a high-frequency solution crosses the upper boundary of the forbidden band there is a bifurcation to a low-frequency solution, and vice versa. Second, the analysis is extended to include the study of braking and locking of tearing mode rotation by the interaction of the mode with an error-field. It is found that this interaction can brake the plasma rotation, suppress magnetic island evolution and drive locked modes.

Download or read book Tearing Mode Activity in the Phaedrus T Tokamak written by Binsheng Cui and published by . This book was released on 1993 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Threshold Condition for Nonlinear Tearing Modes in Tokamaks written by and published by . This book was released on 1996 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low-mode-number tearing, mode nonlinear evolution is analyzed emphasizing the need for a threshold condition, to account for observations in tokamaks. The discussion is illustrated by two models recently introduced in the literature. The models can be compared with the available data and/or serve as a basis for planning some experiments in order to either test theory (by means of beta-limit scaling laws, as proposed in this paper) or attempt to control undesirable tearing modes. Introducing a threshold condition in the tearing mode stability analysis is found to reveal some bifurcation points and thus domains of intrinsic stability in the island dynamics operational space.

Download or read book Computational Modeling of Neoclassical and Resistive MHD Tearing Modes in Tokamaks written by Thomas A. Gianakon and published by . This book was released on 1996 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stability of Tearing Modes in Tokamak Plasmas written by C.C. Hegna and published by . This book was released on 1994 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Coupling of Tearing Modes in Tokamaks written by J. Michael Finn and published by . This book was released on 1977 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book University of Wisconsin Center for Plasma Theory and Computation Report written by and published by . This book was released on 1989 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nonlinear Tearing Modes in Tokamaks written by R. B. White and published by . This book was released on 1976 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kink and Tearing Mode Instabilities in a Tokamak written by O.P. Pogutse and published by . This book was released on 1977 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Turbulent Stabilization of the Tearing Mode in Tokamak Plasmas written by E. Esarey and published by . This book was released on 1985 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book TEARING MODES IN TOKAMAKS WITH LOWER HYBRID CURRENT DRIVE written by X.Q. XU and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Neoclassical Tearing Modes in Tokamak Fusion Test Reactor Experiments Part I Measurements of Magnetic Islands and Delta Prime written by and published by . This book was released on 1997 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tearing type modes are observed in most high-confinement operation regimes in TFTR. Three different methods are used to measure the magnetic island widths: external magnetic coils, internal temperature fluctuation from electron cyclotron emission (ECE) diagnostic and an experiment where the plasma major radius is rapidly shifted ('Jog' experiments). A good agreement between the three methods is observed. Numerical and analytic calculations of delta prime (the tearing instability index) are compared with an experimental measurement of delta prime using the tearing mode eigenfunction mapped from the Jog data. The obtained negative delta prime indicates that the observed tearing modes cannot be explained by the classical current-gradient-driven tearing theory.

Download or read book Reduced MHD modeling of tearing mode interactions in Tokamaks written by J. W. Eastwood and published by . This book was released on 1986 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reduced Equations for Finite Beta Tearing Modes in Tokamaks written by and published by . This book was released on 1984 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Toroidal effects on tearing mode instabilities in tokamaks written by George Lee Flint and published by . This book was released on 1973 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: