Download or read book Quiet Periods in Edge Turbulence Preceding the L H Transition in NSTX written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes the first observations in NSTX of 'quiet periods' in the edge turbulence preceding the L-H transition, as diagnosed by the GPI diagnostic near the outer midplane separatrix. During these quiet periods the GPI D[alpha] light emission pattern was transiently similar to that seen during Hmode, i.e. with a relatively small fraction of the GPI light emission located outside the separatrix. These quiet periods had a frequency of ~3 kHz for at least 30 msec before the L-H transition, and were correlated with changes in the direction of the local poloidal velocity. The GPI turbulence images were also analyzed to obtain an estimate for the dimensionless poloidal shearing S =(dVp/dr)(Lr/Lp)[tau]. The values of S were strongly modulated by the quiet periods, but not otherwise varying for at least 30 msec preceding the L-H transition. Since neither the quiet periods nor the shear flow increased significantly immediately preceding the L-H transition, neither of these appears to be the trigger for this transition, at least for these cases in NSTX.
Download or read book H Mode Turbulence Power Threshold ELM and Pedestal Studies in NSTX written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High-confinement mode (H-mode) operation plays a crucial role in NSTX [National Spherical Torus Experiment] research, allowing higher beta limits due to reduced plasma pressure peaking, and long-pulse operation due to high bootstrap current fraction. Here, new results are presented in the areas of edge localized modes (ELMs), H-mode pedestal physics, L-H turbulence, and power threshold studies. ELMs of several other types (as observed in conventional aspect ratio tokamaks) are often observed: (1) large, Type I ELMs, (2) ''medium'' Type II/III ELMs, and (3) giant ELMs which can reduce stored energy by up to 30% in certain conditions. In addition, many high-performance discharges in NSTX have tiny ELMs (newly termed Type V), which have some differences as compared with ELM types in the published literature. The H-mode pedestal typically contains between 25-33% of the total stored energy, and the NSTX pedestal energy agrees reasonably well with a recent international multi-machine scaling. We find that the L-H transition occurs on a [approx]100 [micro]sec timescale as viewed by a gas puff imaging diagnostic, and that intermittent quiescent periods precede the final transition. A power threshold identity experiment between NSTX and MAST shows comparable loss power at the L-H transition in balanced double-null discharges. Both machines require more power for the L-H transition as the balance is shifted toward lower single null. High field side gas fueling enables more reliable H-mode access, but does not always lead to a lower power threshold e.g., with a reduction of the duration of early heating. Finally the edge plasma parameters just before the L-H transition were compared with theories of the transition. It was found that while some theories can separate well-developed L- and H-mode data, they have little predictive value.
Download or read book H Mode Turbulence PowerThreshold ELM and Pedestal Studies in NSTX written by R. Maingi and published by . This book was released on 2004 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Plasma Boundary of Magnetic Fusion Devices written by P.C Stangeby and published by CRC Press. This book was released on 2000-01-01 with total page 738 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Plasma Boundary of Magnetic Fusion Devices introduces the physics of the plasma boundary region, including plasma-surface interactions, with an emphasis on those occurring in magnetically confined fusion plasmas. The book covers plasma-surface interaction, Debye sheaths, sputtering, scrape-off layers, plasma impurities, recycling and control, 1D and 2D fluid and kinetic modeling of particle transport, plasma properties at the edge, diverter and limiter physics, and control of the plasma boundary. Divided into three parts, the book begins with Part 1, an introduction to the plasma boundary. The derivations are heuristic and worked problems help crystallize physical intuition, which is emphasized throughout. Part 2 provides an introduction to methods of modeling the plasma edge region and for interpreting computer code results. Part 3 presents a collection of essays on currently active research hot topics. With an extensive bibliography and index, this book is an invaluable first port-of-call for researchers interested in plasma-surface interactions.
Download or read book Nuclear Fusion written by Edward Morse and published by Springer. This book was released on 2018-10-15 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt: The pursuit of nuclear fusion as an energy source requires a broad knowledge of several disciplines. These include plasma physics, atomic physics, electromagnetics, materials science, computational modeling, superconducting magnet technology, accelerators, lasers, and health physics. Nuclear Fusion distills and combines these disparate subjects to create a concise and coherent foundation to both fusion science and technology. It examines all aspects of physics and technology underlying the major magnetic and inertial confinement approaches to developing nuclear fusion energy. It further chronicles latest developments in the field, and reflects the multi-faceted nature of fusion research, preparing advanced undergraduate and graduate students in physics and engineering to launch into successful and diverse fusion-related research. Nuclear Fusion reflects Dr. Morse’s research in both magnetic and inertial confinement fusion, working with the world’s top laboratories, and embodies his extensive thirty-five year career in teaching three courses in fusion plasma physics and fusion technology at University of California, Berkeley.
Download or read book Fundamentals of Plasma Physics and Controlled Fusion written by Kenrō Miyamoto and published by . This book was released on 1997 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Fusion written by C.M. Braams and published by CRC Press. This book was released on 2002-06-20 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fusion research started over half a century ago. Although the task remains unfinished, the end of the road could be in sight if society makes the right decisions. Nuclear Fusion: Half a Century of Magnetic Confinement Fusion Research is a careful, scholarly account of the course of fusion energy research over the past fifty years. The authors outline the different paths followed by fusion research from initial ignorance to present understanding. They explore why a particular scheme would not work and why it was more profitable to concentrate on the mainstream tokamak development. The book features descriptive sections, in-depth explanations of certain physical and technical issues, scientific terms, and an extensive glossary that explains relevant abbreviations and acronyms.
Download or read book Tokamak Engineering Mechanics written by Yuntao Song and published by Springer Science & Business Media. This book was released on 2013-09-20 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tokamak Engineering Mechanics offers concise and thorough coverage of engineering mechanics theory and application for tokamaks, and the material is reinforced by numerous examples. Chapter topics include general principles, static mechanics, dynamic mechanics, thermal fluid mechanics and multiphysics structural mechanics of tokamak structure analysis. The theoretical principle of the design and the methods of the analysis for various components and load conditions are presented, while the latest engineering technologies are also introduced. The book will provide readers involved in the study of mechanical/fusion engineering with a general understanding of tokamak engineering mechanics. Yuntao Song is Head of the Tokamak Design Division at the Institute of Plasma Physics, Chinese Academic of Science (ASIPP), China.
Download or read book The Fairy Tale of Nuclear Fusion written by L. J. Reinders and published by Springer Nature. This book was released on 2021-05-20 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: This carefully researched book presents facts and arguments showing, beyond a doubt, that nuclear fusion power will not be technically feasible in time to satisfy the world's urgent need for climate-neutral energy. The author describes the 70-year history of nuclear fusion; the vain attempts to construct an energy-generating nuclear fusion power reactor, and shows that even in the most optimistic scenario nuclear fusion, in spite of the claims of its proponents, will not be able to make a sizable contribution to the energy mix in this century, whatever the outcome of ITER. This implies that fusion power will not be a factor in combating climate change, and that the race to save the climate with carbon-free energy will have been won or lost long before the first nuclear fusion power station comes on line. Aimed at the general public as well as those whose decisions directly affect energy policy, this book will be a valuable resource for informing future debates.
Download or read book Plasma Surface Interactions in Controlled Fusion Devices written by and published by . This book was released on 1978 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fusion Physics written by Mitsuru Kikuchi and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides an introduction to nuclear fusion and its status and prospects, and features specialized chapters written by leaders in the field, presenting the main research and development concepts in fusion physics. At over 1100 pages, this publication provides an unparalleled resource for fusion physicists and engineers.
Download or read book Introduction to Plasma Physics and Controlled Fusion written by Francis F. Chen and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: TO THE SECOND EDITION In the nine years since this book was first written, rapid progress has been made scientifically in nuclear fusion, space physics, and nonlinear plasma theory. At the same time, the energy shortage on the one hand and the exploration of Jupiter and Saturn on the other have increased the national awareness of the important applications of plasma physics to energy production and to the understanding of our space environment. In magnetic confinement fusion, this period has seen the attainment 13 of a Lawson number nTE of 2 x 10 cm -3 sec in the Alcator tokamaks at MIT; neutral-beam heating of the PL T tokamak at Princeton to KTi = 6. 5 keV; increase of average ß to 3%-5% in tokamaks at Oak Ridge and General Atomic; and the stabilization of mirror-confined plasmas at Livermore, together with injection of ion current to near field-reversal conditions in the 2XIIß device. Invention of the tandem mirror has given magnetic confinement a new and exciting dimension. New ideas have emerged, such as the compact torus, surface-field devices, and the EßT mirror-torus hybrid, and some old ideas, such as the stellarator and the reversed-field pinch, have been revived. Radiofrequency heat ing has become a new star with its promise of dc current drive. Perhaps most importantly, great progress has been made in the understanding of the MHD behavior of toroidal plasmas: tearing modes, magnetic Vll Vlll islands, and disruptions.
Download or read book Fundamentals of Plasma Physics and Controlled Fusion written by Kenrō Miyamoto and published by . This book was released on 2001 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ideal MHD written by Jeffrey P. Freidberg and published by Cambridge University Press. This book was released on 2014-06-26 with total page 743 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive, self-contained, and clearly written, this book describes the macroscopic equilibrium and stability of high temperature plasmas.
Download or read book Transport and Structural Formation in Plasmas written by Kimitaka Itoh and published by CRC Press. This book was released on 1999-01-01 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph, the latest in the IOP Plasma Physics Series, written by three of the most senior and internationally respected Japanese fusion scientists, presents a self-consistent picture of turbulent transport, structural formation and transitions-processes that are typical of the physics of many far from equilibrium systems such as exist in magnetically confined and inhomogeneous plasmas. The Author's view is that the plasma structure, fluctuations and turbulent transport are continually regulating each other and, in addition, that the structural formation and structural transition of plasmas are typical of the physics of far from equilibrium systems. The book presents and explains why the plasma inhomogeneity is the ordering parameter governing transport and how self-sustained fluctuations can be driven through subcritical excitation even beyond linear stability. In addition, the authors derive the non-linear gradient-flux relation with the result that asymmetry arising from the fluctuations allows mixing of the various kinds of fluxes. This emphasises the ever important role that electromagnetic fields play in inducing long range interactions, couplings and bifurcations in plasmas. To illustrate, a transport simulation of a high temperature current fusion experiment like JET-the Joint European Torus-helps us to understand various structural formations such as the H-mode. With the insight that structural formation in high temperature plasmas is fundamental to an accurate description of the basic phenomena that occur in our present cosmos, the authors provide a comprehensive account of the subject to help fusion researchers, fluid dynamicists and astrophysicists alike. The book addresses a key to understanding the age old question of what has occurred in the early stage of the our universe and what is likely to occur in the final stage of our universe.
Download or read book Controlled Nuclear Fusion written by Samuel Glasstone and published by . This book was released on 1968 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measuring Discharge with Acoustic Doppler Current Profilers from a Moving Boat written by David S. Mueller and published by CreateSpace. This book was released on 2014-06-16 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mission of the U.S. Geological Survey (USGS) Water Resources Discipline is to provide the information and understanding needed for wise management of the Nation's water resources. Inherent in this mission is the responsibility of collecting data that accurately describe the physical, chemical, and biological attributes of water systems. These data are used for environmental and resource assessments by the USGS, other government agencies and scientific organizations, and the general public. Reliable and quality-assured data are essential to the credibility and impartiality of the water-resources appraisals carried out by the USGS.
