Download or read book Migration of Artificially Introduced Micron Size Carbon Dust in the DIII D Divertor written by and published by . This book was released on 2006 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Migration of pre-characterized carbon dust in a tokamak environment was studied by introducing about 30 milligrams of dust flakes 5-10 [mu]m in diameter in the lower divertor of DIII-D using the DiMES sample holder. The dust was exposed to high power ELMing Hmode discharges in lower-single-null magnetic configuration with the strike points swept across the divertor floor. When the outer strike point (OSP) passed over the dust holder exposing it to high particle and heat fluxes, part of the dust was injected into the plasma. In about 0.1 sec following the OSP pass over the dust, 1-2% of the total dust carbon content (2-4 x 1019 carbon atoms, equivalent to a few million dust particles) penetrated the core plasma, raising the core carbon density by a factor of 2-3. When the OSP was inboard of the dust holder, the dust injection continued at a lower rate. Individual dust particles were observed moving at velocities of 10-100 m/s, predominantly in the toroidal direction for deuteron flow to the outer divertor target, consistent with the ion drag force. The observed behavior of the dust is in qualitative agreement with modeling by the 3D DustT code.
Download or read book On the Edge of Magnetic Fusion Devices written by Sergei Krasheninnikov and published by Springer Nature. This book was released on 2020-09-07 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the current state of understanding concerning edge plasma, which bridges hot fusion plasma, with a temperature of roughly one million degrees Kelvin with plasma-facing materials, which have melting points of only a few thousand degrees Kelvin. In a fact, edge plasma is one of the keys to solution for harnessing fusion energy in magnetic fusion devices. The physics governing the processes at work in the edge plasma involves classical and anomalous transport of multispecies plasma, neutral gas dynamics, atomic physics effects, radiation transport, plasma-material interactions, and even the transport of plasma species within the plasma-facing materials. The book starts with simple physical models, then moves on to rigorous theoretical considerations and state-of-the-art simulation tools that are capable of capturing the most important features of the edge plasma phenomena. The authors compare the conclusions arising from the theoretical and computational analysis with the available experimental data. They also discuss the remaining gaps in their models and make projections for phenomena related to edge plasma in magnetic fusion reactors.
Download or read book Dust Studies in DIII D and TEXTOR written by and published by . This book was released on 2009 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies of naturally occurring and artificially introduced carbon dust are conducted in DIII-D and TEXTOR. In DIII-D, dust does not present operational concerns except immediately after entry vents. Submicron sized dust is routinely observed using Mie scattering from a Nd:Yag laser. The source is strongly correlated with the presence of Type I edge localized modes (ELMs). Larger size (0.005-1 mm diameter) dust is observed by optical imaging, showing elevated dust levels after entry vents. Inverse dependence of the dust velocity on the inferred dust size is found from the imaging data. Direct heating of the dust particles by the neutral beam injection (NBI) and acceleration of dust particles by the plasma flows are observed. Energetic plasma disruptions produce significant amounts of dust. Large flakes or debris falling into the plasma may result in a disruption. Migration of pre-characterized carbon dust is studied in DIII-D and TEXTOR by introducing micron-size dust in plasma discharges. In DIII-D, a sample holder filled with (almost equal to)30 mg of dust is introduced in the lower divertor and exposed to high-power ELMing H-mode discharges with strike points swept across the divertor floor. After a brief exposure ((almost equal to)0.1 s) at the outer strike point, part of the dust is injected into the plasma, raising the core carbon density by a factor of 2-3 and resulting in a twofold increase of the radiated power. In TEXTOR, instrumented dust holders with 1-45 mg of dust are exposed in the scrape-off layer 0-2 cm radially outside of the last closed flux surface in discharges heated with neutral beam injection (NBI) power of 1.4 MW. At the given configuration of the launch, the dust did not penetrate the core plasma and only moderately perturbed the edge plasma, as evidenced by an increase of the edge carbon content.
Download or read book Multifacets of Dusty Plasmas written by José Tito Mendonça and published by American Institute of Physics. This book was released on 2008-09-26 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dusty plasmas are relevant to the understanding of astrophysical, space and laboratory phenomena. During the ICPDP5, the progress in observations, modeling and simulations of dusty plasma physics has been examined. This conference addressed a very broad range oftopics which are closely related through the underlying physics, including contributions from Fusion and Astrophysics.
Download or read book Observation of Dust in DIII D Divertor and SOL by Visible Imaging written by and published by . This book was released on 2007 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dust is commonly found in fusion devices. Though generally of no concern in the present day machines, dust may pose serious safety and operational concerns for ITER. Micron-size dust usually dominates the samples collected from tokamaks. During a plasma discharge micron-size dust particles can become highly mobile and travel over distances of a few meters. Once inside the plasma, dust particles heat up to over 3000 K and emit thermal radiation that can be detected by visible imaging techniques. Observations of naturally occurring and artificially introduced dusts have been performed in DIII-D divertor and scrape-off layer (SOL) using standard frame rate CMOS cameras, a gated-intensified CID camera, and a fast-framing CMOS camera. In the first 2-3 plasma discharges after a vent with personnel entry inside the vacuum vessel ('dirty vent') dust levels were quite high with thousands of particles observed in each discharge. Individual particles moving at velocities of up to a few hundred m/s and breakup of larger particles into pieces were observed. After about 15 discharges dust was virtually gone during the stationary portion of a discharge, and appeared at much reduced levels during the plasma initiation and termination phases. After a few days of plasma operations (about 70 discharges) dust levels were further reduced to just a few observed events per discharge except in discharges with current disruptions that produced significant amounts of dust. An injection of a few milligram of micron-size (6 micron median diameter) carbon dust into a high-power lower single-null ELMing H-mode discharge with strike points swept across the lower divertor floor was performed. A significant increase of the core carbon radiation was observed for about 250 ms after the injection, as the total radiated power increased twofold. Dust particles from the injection were observed by the fast framing camera in the outboard SOL near the midplane. The amount of dust observed by the fast camera immediately after the injection was.
Download or read book Particle Flows in Pumped DIII D Discharges written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The dynamics of particle flows in the DIII-D tokamak for two divertor configurations is considered. Fuel and intrinsic carbon impurity flows are analyzed using experimental data and 2D fluid plasma simulations. The flows in puff and pump experiments done in an open and a closed divertor geometry are described. It is shown that the flow of fuel particles is sensitive to divertor geometry. The pumping efficiency of the DIII-D cryopumps is a factor of 2 higher in a closed geometry than an open. The core refueling rate of an open divertor is a factor of 2 higher than that of a closed divertor. In contrast, the flow of impurity carbon particles is insensitive to divertor geometry. Both the core carbon content and the fraction of the carbon source which penetrates to the core is unchanged between an open and closed divertor. In addition, the core impurity content is found to be insensitive to the amplitude of gas puffing in the simulations.
Download or read book On the Edge of Magnetic Fusion Devices written by Sergei Krasheninnikov and published by Springer. This book was released on 2021-09-09 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the current state of understanding concerning edge plasma, which bridges hot fusion plasma, with a temperature of roughly one million degrees Kelvin with plasma-facing materials, which have melting points of only a few thousand degrees Kelvin. In a fact, edge plasma is one of the keys to solution for harnessing fusion energy in magnetic fusion devices. The physics governing the processes at work in the edge plasma involves classical and anomalous transport of multispecies plasma, neutral gas dynamics, atomic physics effects, radiation transport, plasma-material interactions, and even the transport of plasma species within the plasma-facing materials. The book starts with simple physical models, then moves on to rigorous theoretical considerations and state-of-the-art simulation tools that are capable of capturing the most important features of the edge plasma phenomena. The authors compare the conclusions arising from the theoretical and computational analysis with the available experimental data. They also discuss the remaining gaps in their models and make projections for phenomena related to edge plasma in magnetic fusion reactors.
Download or read book Star Power written by Alain Bécoulet and published by MIT Press. This book was released on 2023-09-19 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: A concise and accessible explanation of the science and technology behind the domestication of nuclear fusion energy. Nuclear fusion research tells us that the Sun uses one gram of hydrogen to make as much energy as can be obtained by burning eight tons of petroleum. If nuclear fusion—the process that makes the stars shine—could be domesticated for commercial energy production, the world would gain an inexhaustible source of energy that neither depletes natural resources nor produces greenhouse gases. In Star Power, Alan Bécoulet offers a concise and accessible primer on fusion energy, explaining the science and technology of nuclear fusion and describing the massive international scientific effort to achieve commercially viable fusion energy. Bécoulet draws on his work as Head of Engineering at ITER (International Thermonuclear Experimental Reactor) to explain how scientists are trying to “put the sun in a box.” He surveys the history of nuclear power, beginning with post–World War II efforts to use atoms for peaceful purposes and describes how energy is derived from fusion, explaining that the essential principle of fusion is based on the capacity of nucleons (protons and neutrons) to assemble and form structures (atomic nuclei) in spite of electrical repulsion between protons, which all have a positive charge. He traces the evolution of fusion research and development, mapping the generation of electric current though fusion. The ITER project marks a giant step in the development of fusion energy, with the potential to demonstrate the feasibility of a nuclear fusion reactor. Star Power offers an introduction to what may be the future of energy production.
Download or read book Bringing Fusion to the U S Grid written by National Academies of Sciences Engineering and Medicine and published by . This book was released on 2021-11-17 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fusion energy offers the prospect of addressing the nation's energy needs and contributing to the transition to a low-carbon emission electrical generation infrastructure. Technology and research results from U.S. investments in the major fusion burning plasma experiment known as ITER, coupled with a strong foundation of research funded by the Department of Energy (DOE), position the United States to begin planning for its first fusion pilot plant. Strong interest from the private sector is an additional motivating factor, as the process of decarbonizing and modernizing the nation's electric infrastructure accelerates and companies seek to lead the way. At the request of DOE, Bringing Fusion to the U.S. Grid builds upon the work of the 2019 report Final Report of the Committee on a Strategic Plan for U.S. Burning Plasma Research to identify the key goals and innovations - independent of confinement concept - that are needed to support the development of a U.S. fusion pilot plant that can serve as a model for producing electricity at the lowest possible capital cost.
Download or read book Fusion Technology 1994 written by K. Herschbach and published by Newnes. This book was released on 2012-12-02 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the Symposium on Fusion Technology (SOFT) conference is to set the stage for the exchange of information on the design, construction, and operation of fusion experiments and the technology which is being developed for the next-step devices and for fusion reactors. These proceedings therefore present an up-to-date and throrough review of the state-of-the art in this dynamic field.
Download or read book Plasma Material Interactions in a Controlled Fusion Reactor written by Tetsuo Tanabe and published by Springer Nature. This book was released on 2021-03-08 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a primer on the interplay between plasma and materials in a fusion reactor, so-called plasma–materials interactions (PMIs), highlighting materials and their influence on plasma through PMI. It aims to demonstrate that a plasma-facing surface (PFS) responds actively to fusion plasma and that the clarifying nature of PFS is indispensable to understanding the influence of PFS on plasma. It describes the modern insight into PMI, namely, relevant feedback to plasma performance from plasma-facing material (PFM) on changes in a material surface by plasma power load by radiation and particles, contrary to a conventional view that unilateral influence from plasma on PFM is dominant in PMI. There are many books and reviews on PMI in the context of plasma physics, that is, how plasma or plasma confinement works in PMI. By contrast, this book features a materials aspect in PMI focusing on changes caused by heat and particle load from plasma: how PFMs are changed by plasma exposure and then, accordingly, how the changed PFM interacts with plasma.
Download or read book Fundamentals of Magnetic Thermonuclear Reactor Design written by Vasilij A. Glukhikh and published by Woodhead Publishing. This book was released on 2018-05-21 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of Magnetic Thermonuclear Reactor Design is a comprehensive resource on fusion technology and energy systems written by renowned scientists and engineers from the Russian nuclear industry. It brings together a wealth of invaluable experience and knowledge on controlled thermonuclear fusion (CTF) facilities with magnetic plasma confinement – from the first semi-commercial tokamak T-3, to the multi-billion international experimental thermonuclear reactor ITER, now in construction in France. As the INTOR and ITER projects have made an immense contribution in the past few decades, this book focuses on its practical engineering aspects and the basics of technical physics and electrical engineering. Users will gain an understanding of the key ratios between plasma and technical parameters, design streamlining algorithms and engineering solutions. Written by a team of qualified experts who have been involved in the design of thermonuclear reactors for over 50 years Outlines the most important features of the ITER project in France which is building the largest tokamak, including the design, material selection, safety and economic considerations Includes data on how to design magnetic fusion reactors using CAD tools, along with relevant regulatory documents
Download or read book New Frontiers in Physics written by Tepper L. Gill and published by . This book was released on 1996 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Safe Handling of Tritium written by International Atomic Energy Agency and published by . This book was released on 1991 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication contains information on the dosimetry and monitoring of tritium, the use of protective clothing for work with tritium, safe practices in tritium handling laboratories and details of tritium compatible materials. The information has been compiled from experience in the various applications of tritium and should represent valuable source material to all users of tritium, including those involved in fusion R&D.
Download or read book Plasma Kinetics in Atmospheric Gases written by M. Capitelli and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emphasis is placed on the analysis of translational, rotational, vibrational and electronically excited state kinetics, coupled to the electron Boltzmann equation.
Download or read book Quantum Mechanics and Statistical Mechanics written by and published by Krishna Prakashan Media. This book was released on with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atomic and Plasma material Interaction Data for Fusion written by and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
