Thermonuclear Instabilities and Plasma Edge Transport in Tokamaks

Thermonuclear Instabilities and Plasma Edge Transport in Tokamaks PDF Author: Tünde Fülöp
Publisher:
ISBN: 9789171978417
Category :
Languages : en
Pages : 47

Book Description


Tokamak Plasma

Tokamak Plasma PDF Author: B. B. Kadomtsev
Publisher: CRC Press
ISBN:
Category : Art
Languages : en
Pages : 242

Book Description
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.

Theory of Tokamak Plasmas

Theory of Tokamak Plasmas PDF Author: R.B. White
Publisher: Elsevier
ISBN: 1483293262
Category : Science
Languages : en
Pages : 374

Book Description
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.

Tokamaks

Tokamaks PDF Author: John Wesson
Publisher: Oxford University Press
ISBN: 0199592233
Category : Science
Languages : en
Pages : 828

Book Description
The tokamak is the principal tool in controlled fusion research. This book acts as an introduction to the subject and a basic reference for theory, definitions, equations, and experimental results. The fourth edition has been completely revised, describing their development of tokamaks to the point of producing significant fusion power.

Magnetohydrodynamic Stability of Tokamaks

Magnetohydrodynamic Stability of Tokamaks PDF Author: Hartmut Zohm
Publisher: John Wiley & Sons
ISBN: 3527677364
Category : Science
Languages : en
Pages : 240

Book Description
This book bridges the gap between general plasma physics lectures and the real world problems in MHD stability. In order to support the understanding of concepts and their implication, it refers to real world problems such as toroidal mode coupling or nonlinear evolution in a conceptual and phenomenological approach. Detailed mathematical treatment will involve classical linear stability analysis and an outline of more recent concepts such as the ballooning formalism. The book is based on lectures that the author has given to Master and PhD students in Fusion Plasma Physics. Due its strong link to experimental results in MHD instabilities, the book is also of use to senior researchers in the field, i.e. experimental physicists and engineers in fusion reactor science. The volume is organized in three parts. It starts with an introduction to the MHD equations, a section on toroidal equilibrium (tokamak and stellarator), and on linear stability analysis. Starting from there, the ideal MHD stability of the tokamak configuration will be treated in the second part which is subdivided into current driven and pressure driven MHD. This includes many examples with reference to experimental results for important MHD instabilities such as kinks and their transformation to RWMs, infernal modes, peeling modes, ballooning modes and their relation to ELMs. Finally the coverage is completed by a chapter on resistive stability explaining reconnection and island formation. Again, examples from recent tokamak MHD such as sawteeth, CTMs, NTMs and their relation to disruptions are extensively discussed.

New Ideas in Tokamak Confinement

New Ideas in Tokamak Confinement PDF Author: Marshall N. Rosenbluth
Publisher: Springer Science & Business Media
ISBN: 9781563961311
Category : Science
Languages : en
Pages : 514

Book Description
Market: Scientists and students involved in thermonuclear fusion research. Thermonuclear fusion research using the confinement device tokamak represents one of the most prominent science projects in the second half of the 20th century. International Tokamak Community is now committing significant effort and funds to experiments with burning plasma, hot and dense enough to produce significant nuclear fusion reactions. The methods used to enhance tokamak performance have a profound and immediate effect on machine design. This book provides an up-to-date account of research in tokamak fusion and puts forward innovative ideas in confinement physics.

Frontiers in Fusion Research II

Frontiers in Fusion Research II PDF Author: Mitsuru Kikuchi
Publisher: Springer
ISBN: 3319189050
Category : Technology & Engineering
Languages : en
Pages : 412

Book Description
This book reviews recent progress in our understanding of tokamak physics related to steady state operation, and addresses the scientific feasibility of a steady state tokamak fusion power system. It covers the physical principles behind continuous tokamak operation and details the challenges remaining and new lines of research towards the realization of such a system. Following a short introduction to tokamak physics and the fundamentals of steady state operation, later chapters cover parallel and perpendicular transport in tokamaks, MHD instabilities in advanced tokamak regimes, control issues, and SOL and divertor plasmas. A final chapter reviews key enabling technologies for steady state reactors, including negative ion source and NBI systems, Gyrotron and ECRF systems, superconductor and magnet systems, and structural materials for reactors. The tokamak has demonstrated an excellent plasma confinement capability with its symmetry, but has an intrinsic drawback with its pulsed operation with inductive operation. Efforts have been made over the last 20 years to realize steady state operation, most promisingly utilizing bootstrap current. Frontiers in Fusion Research II: Introduction to Modern Tokamak Physics will be of interest to graduate students and researchers involved in all aspects of tokamak science and technology.

Control of Internal Transport Barriers in Magnetically Confined Tokamak Fusion Plasmas

Control of Internal Transport Barriers in Magnetically Confined Tokamak Fusion Plasmas PDF Author: Soma Raj Panta
Publisher:
ISBN:
Category : Plasma (Ionized gases)
Languages : en
Pages : 200

Book Description
In the Tokamak plasma, for fusion to be possible, we have to maintain a very high temperature and density at the core at the same time keeping them low at the edge to protect the machine. Nature does not favor gradients. Gradients are source of free energy that causes instability. But we require a large gradient to get energy from plasma fusion. We therefore, apply a huge magnetic field on the order of few Tesla (1 T-10 T) that confines the plasma in the core, maintaining gradients. Due to gradients in density of charged particles (ions and electrons), there is an electric field in the plasma. Heat and particle transport takes place from core to edge mainly through anomalous transport while the E x B velocity sheer acts to reduce the transport of heat and particles. The regime at which the E x B velocity shear exceeds the maximum linear instability growth rate, as a result, the transport of particles and heat gets locally reduced is termed as the formation of a transport barrier. This regime can be identified by calculating the transport coefficients in the local region. Sometimes it can be observed in the edge where it is called an edge barrier while if it is near the core it is an internal transport barrier. There is a positive feedback loop between gradients and transport barrier formation. External heating and current drives play an important role to control such barriers. Auxiliary heating like neutral beam injection (NBI) and radio frequency (RF) heating can be used at a proper location (near the core of the plasma) to trigger or (far outside from the core) to destroy those barriers. Barrier control mechanism in the burning plasmas in international thermonuclear test reactor (ITER) parameter scenarios employing fusion power along with auxiliary heating source and pellets are studied. Continuous bombardment with pellets in the interval of a fraction of a second near the core of the burning plasma results in a stronger barrier. Frozen pellets along with auxiliary heating are found to be helpful to control the barriers in the tokamak plasmas. Active control mechanism for transport barriers using pellets and auxiliary heating in one of tokamaks in United States (DIII-D) parameter scenarios are presented in which intrinsic hysteresis is used as a novel control tool. During this process, a small background NBI power near the core assists in maintaining the profile. Finally, a self-sustained control mechanism in the presence of core heating is also explored in Japanese tokamak (JT-60SA) parameter scenarios. Centrally peaked narrow NBI power is mainly absorbed by ions with a smaller fraction by the electrons. Heat exchange between the electron and ion channels and heat conduction in the electron channel are found to be the main processes that govern this self control effect. A strong barrier which is formed in the ion channel is found to play the main role during the profile steepening while the burst after the peaked core density is found to have key role in the profile relaxation.

Diagnosis and Control of Plasma Instabilities in TOKAMAKs

Diagnosis and Control of Plasma Instabilities in TOKAMAKs PDF Author: Mohsen Davoudi
Publisher: LAP Lambert Academic Publishing
ISBN: 9783659230813
Category :
Languages : en
Pages : 172

Book Description
A crucial problem of research in thermonuclear plasma physics in Tokamaks is the control of rotating helical magnetic perturbations, associated with local distortions of the current density profile. These unstable perturbations (called magnetic islands) can seriously degrade plasma and energy confinement. By injecting energy to the magnetic islands using microwave antennas, a specific magnetic surface layer will be resonance and heated which causes the magnetic islands to disappear. The main goal of this book is to discuss about the implementation of reliable hardware and software structure which is capable of running estimator, observer and controller in real-time to achieve the MHD instability suppression in the FTU (Frascati Tokamak Upgrade) of ENEA in Frascati, Italy in collaboration with IFP-CNR in Milan. Design and realization of signal conditioning and insulation circuit for motor inverters I/O control signals, motors brake control circuit to activate faster motor braking by protection system, and design and implementation of high-speed communication algorithms among the FPGA and DSP modules have been another part of the authors contribution to this research.

Burning Plasma

Burning Plasma PDF Author: National Research Council
Publisher: National Academies Press
ISBN: 0309166918
Category : Science
Languages : en
Pages : 208

Book Description
Significant advances have been made in fusion science, and a point has been reached when we need to decide if the United States is ready to begin a burning plasma experiment. A burning plasmaâ€"in which at least 50 percent of the energy to drive the fusion reaction is generated internallyâ€"is an essential step to reach the goal of fusion power generation. The Burning Plasma Assessment Committee was formed to provide advice on this decision. The committee concluded that there is high confidence in the readiness to proceed with the burning plasma step. The International Thermonuclear Experimental Reactor (ITER), with the United States as a significant partner, was the best choice. Once a commitment to ITER is made, fulfilling it should become the highest priority of the U.S. fusion research program. A funding trajectory is required that both captures the benefits of joining ITER and retains a strong scientific focus on the long-range goals of the program. Addition of the ITER project will require that the content, scope, and level of U.S. fusion activity be defined by program balancing through a priority-setting process initiated by the Office of Fusion Energy Science.