Download or read book Experimental investigations of driven Alfv n wave resonances in a tokamak plasma using carbon dioxide laser interferometry written by Todd Edwin Evans and published by . This book was released on 1984 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental investigation of driven Alfv n wave resonances on the PRETEXT tokamak written by William David Booth and published by . This book was released on 1988 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Study of the Shear Alfven Resonance in a Tokamak written by Franklin Douglas Witherspoon and published by . This book was released on 1984 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tokamak Plasma written by B. B. Kadomtsev and published by CRC Press. This book was released on 1992 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of tokamaks and their role in fusion reactors has been known for some time, but it is only now that plasma physicists have reached a clear understanding of the major principles governing the behaviour of confined high-temperature plasma. This book gives a timely and comprehensive survey of these concepts as well as a simple presentation of the basic physics involved. The topics discussed include: the theory of plasma equilibrium and its main instabilities, semi-empirical approaches for investigating heat transport, major plasma instabilities restricting the region of a tokamak's operating modes, a variety of plasma confinement regimes and other phenomena such as MARFE, magnetic bubbles and fishbones. The author proposes a new mechanism for anomalous heat transport connected with the idea of microscale 'island' structure. The information is presented in a clear and systematic way which will make this book interesting and useful to a broad spectrum of scientists and engineers involved in fusion reactor research. '...an excellent book - authoritative, broad and bristling with insight' Professor R D Hazeltine, The University of Texas at Austin.

Download or read book Fluctuations in a Tokamak Plasma written by R. L. Kubena and published by . This book was released on 1978 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation of low frequency floating potential fluctuations (f d"200 kHz) in a research tokamak plasma using two spatially separated electrostatic probes has been performed. The spectra, correlation length, and the phase velocity of the fluctuations in both the radial and azimuthal direction have been determined. The propagation velocity in the toroidal direction was also measured and was found to be in the direction of electron current flow. The waves traveled azimuthally in the ion diamagnetic drift direction, even after the usual E x B rotation was taken into account. The electron density fluctuations associated with these oscillations were large, [delta]n/n [approximately] 0.35 - 0.50. The spectra were found to have regularly spaced peaks which seemed to be related to specific azimuthal modes (m =1,2,3, ..., etc.) A parametric study was made to determine what effect plasma parameters had on these peaks. During periods of high electron density in the first 2 msec of the plasma lifetime, strong sawtooth type oscillations were observed. These oscillations typically had frequencies of approximately 10 kHz and were also present when large amounts of neutral gas were added during the discharge by a process called "gas puffing." The results are compared with experimental observations made on other plasma devices with electric and magnetic probes and with microwave and CO2 laser scattering techniques. (The scattering measurements are complimentary to the probe measurements since, in the former case, the wavelength is fixed by the scattering angle, but the oscillations could not be spatially localized.) The oscillations in the Caltech torus were probably related to a drift-tearing type instability which is thought to play a major role in the anomalous particle and energy flux observed in tokamaks. Comparisons are made between current theory and the experimental results. However, the theory for the observed oscillations is still in a rudimentary stage of development, and it is hoped that the present investigation will stimulate future analytical work.

Download or read book Current drive and Plasma formation Experiments on the Versator II Tokamak Using Lower hybrid and Electron cyclotron Waves written by Jeffrey Alan Colborn and published by . This book was released on 1992 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Alfven Wave Studies on a Tokamak written by David Kortbawi and published by . This book was released on 1987 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theory of Tokamak Plasmas written by R.B. White and published by North Holland. This book was released on 1989-08-04 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a graduate textbook on tokamak physics, designed to provide a basic introduction to plasma equilibrium, particle orbits, transport, and those ideal and resistive magnetohydrodynamic instabilities which dominate the behavior of a tokamak discharge, and to develop the mathematical methods necessary for their theoretical analysis.

Download or read book Development and Experimental Evaluation of Theoretical Models for Ion Cyclotron Resonance Frequency Heating of Tokamak Plasmas written by Mervi Mantsinen and published by . This book was released on 1999 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radio frequency Heating and Propagation in Tokamak Plasmas in the Ion Cyclotron Range of Frequencies written by Tak Kuen Mau and published by . This book was released on 1977 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Particle Exhaust and Neutral Fueling in Spherical Tokamaks with Resonant Magnetic Perturbation Fields written by Ian Jacob Waters and published by . This book was released on 2018 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Resonant Magnetic Perturbations (RMPs) and Advanced Divertors (ADs) are both promising candidates to be utilized to meet the challenges of power exhaust in future fusion devices. A combination of both approaches is a promising avenue in order to achieve a stable, high performance plasma edge in an integrated way that takes into account divertor heat load limits while allowing for density and impurity control. The latter is of particular importance in spherical tokamaks which feature Edge Localized Mode free high confinement H-mode regimes prone to density rises and core impurity accumulation. The capability to control core densities and particle exhaust in spherical tokamaks needs to be assessed to determine their viability for compact fusion nuclear science facilities. The experimentally observed, density pump-out effect induced by the application of small amplitude RMPs is an important phenomena with respect to density control but its underlying cause is not well understood. One proposed mechanism for this density pump-out is that the opening of formerly confined field lines from the plasma edge enables enhanced parallel exhaust from the core plasma into the scrape-off-layer and to the divertor targets. Further, regions of stochasticity inside the separatrix can lead to enhanced perpendicular transport, even if these field lines do not themselves escape to the wall. Based on magneto-hydrodynamic (MHD) modeling, it has been previously proposed that a particular resonant response to the applied RMP fields--the so called "Edge-Peeling" response--enhances these geometric changes and thus drives enhanced exhaust. How much these mechanisms contribute to the overall pump-out is an open question. Further, how these RMPs impact the fundamental coupling between the plasma core, edge, and scrape-off-layer, through changes to particle fueling and particle exhaust, is the subject of this thesis. The EMC3-EIRENE code is utilized to assess these scenarios on the Mega-Ampere Spherical Tokamak (MAST) and it's upgrade (MAST-U). Initially, work was carried out to validate the theoretical mechanism for enhanced exhaust: that pressure gradients drive flows along open field lines in the plasma edge. Modeling showed that flows generated by local gas puffing are robust to changes in plasma parameters, and ultimately are a fundamental feature that can be experimentally validated. The underlying mechanism of static pressure driven flows was resolved with a 1D model. Modeling was then used to study the impact of RMP fields specifically. The inclusion of plasma response (from a resistive single fluid MHD model) in the RMP fields shows a more moderate response of density and temperature to the RMPs than does a vacuum field approach in MAST lower single null discharges. In this scenario, enhanced exhaust is shown to contribute to the density pump-out, but the modeled confinement changes underpredict the impact expected from analysis of experiments. Applying this same approach in MAST double null discharges--a second test case from experiment--shows that the addition of RMPs with the single fluid Edge-Peeling response does not cause a consistent pump-out signature in the modeling. This numerical finding of no density pump-out is in contrast to experimental observations for such configurations. This is found in spite of the fact that field lines are escaping the confined region, pressure driven flows are formed, and characteristic lobe structures appear in the plasma edge. This study has shown in a consistent manner that pressure driven flows along field lines are a viable mechanism to govern the plasma particle exhaust from the edge reservoir. If 3D magnetic flux bundles generated by RMP fields connect to regions deep inside of the separatrix, the parallel pressure gradient towards divertor targets will drive enhanced particle flux out of the formerly confined region of the plasma. If the length scale of connection is too long such that the parallel pressure gradient can not be maintained, the flow vanishes, and in spite of the nominal 3D structures in the magnetic field, no impact on particle exhaust is seen. This finding is important for the efforts to understand plasma exhaust with RMP fields. The mere existence of the 3D lobes of the separatrix, formed by the RMP fields, is not sufficient to explain the plasma density pump out alone. But for plasma scenarios with short connection length, and magnetic fields characterized by steep radial gradients they are a viable contributor.

Download or read book Experimental Observations of MHD Activity and Alfven Waves in a Tokamak Plasma written by Louis Robert Giannone and published by . This book was released on 1986 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book On the Evaluation of Currents in a Tokamak Plasma During Combined Ohmic and RF Current Drive written by Dieter Eckhartt and published by . This book was released on 1986 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Observation of Energetic Particle Driven Modes Relevant to Advanced Tokamak Regimes written by R. Nazikian and published by . This book was released on 2004 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Resonance and Synergy Effects on Fast Ion Transport in Tokamaks written by Majid Khan and published by LAP Lambert Academic Publishing. This book was released on 2012 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of today's most challenging issues in energy physics and engineering is the utilization of nuclear fusion power which can provide a lasting energy supply on earth. In the context of designing and developing magnetic confinement fusion reactors, the behavior of high-energetic ions in tokamaks deserves careful examination in theory, experiments and simulations since these ions play a crucial role in achieving and sustaining favorable fusion conditions in the fuel plasma. Thus a burning deuterium (D)-tritium (T) plasma tends to become self-heated by fusion born alphas. Therefore the behavior of energetic alpha particles in a D-T fusion reactor, i.e. their transport and losses as well as their impact on plasma stability must be well understood. In this book we examine the trajectories and diffusion properties of fast alpha particles in a tokamak reactor. For that we employ an orbit following code using a symplectic integration algorithm which allows for accurate calculations of the ion trajectories over long time periods, even in the presence of magnetic and electric field perturbations. The investigations presented in the book are of scientific importance to fusion research.

Download or read book Tokamak Plasma Wave Studies Via Multi channel Far Infrared Laser Scattering written by Hyeon Keo Park and published by . This book was released on 1984 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tokamak Plasma Interaction with Limiters written by Charles Spencer Pitcher and published by . This book was released on 1988 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: