DOCSLIB.ORG

Formation of Hot, Stable, Long-Lived Field-Reversed Configuration Plasmas on the C-2W Device

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Formation of Hot, Stable, Long-Lived Field-Reversed Configuration Plasmas on the C-2W Device IOP Nuclear Fusion International Atomic Energy Agency Nuclear Fusion Nucl. Fusion Nucl. Fusion 59 (2019) 112009 (16pp) https://doi.org/10.1088/1741-4326/ab0be9 59 Formation of hot, stable, long-lived 2019 field-reversed configuration plasmas © 2019 IAEA, Vienna on the C-2W device NUFUAU H. Gota1 , M.W. Binderbauer1 , T. Tajima1, S. Putvinski1, M. Tuszewski1, 1 1 1 1 112009 B.H. Deng , S.A. Dettrick , D.K. Gupta , S. Korepanov , R.M. Magee1 , T. Roche1 , J.A. Romero1 , A. Smirnov1, V. Sokolov1, Y. Song1, L.C. Steinhauer1 , M.C. Thompson1 , E. Trask1 , A.D. Van H. Gota et al Drie1, X. Yang1, P. Yushmanov1, K. Zhai1 , I. Allfrey1, R. Andow1, E. Barraza1, M. Beall1 , N.G. Bolte1 , E. Bomgardner1, F. Ceccherini1, A. Chirumamilla1, R. Clary1, T. DeHaas1, J.D. Douglass1, A.M. DuBois1 , A. Dunaevsky1, D. Fallah1, P. Feng1, C. Finucane1, D.P. Fulton1, L. Galeotti1, K. Galvin1, E.M. Granstedt1 , M.E. Griswold1, U. Guerrero1, S. Gupta1, Printed in the UK K. Hubbard1, I. Isakov1, J.S. Kinley1, A. Korepanov1, S. Krause1, C.K. Lau1 , H. Leinweber1, J. Leuenberger1, D. Lieurance1, M. Madrid1, NF D. Madura1, T. Matsumoto1, V. Matvienko1, M. Meekins1, R. Mendoza1, R. Michel1, Y. Mok1, M. Morehouse1, M. Nations1 , A. Necas1, 1 1 1 1 1 10.1088/1741-4326/ab0be9 M. Onofri , D. Osin , A. Ottaviano , E. Parke , T.M. Schindler , J.H. Schroeder1, L. Sevier1, D. Sheftman1 , A. Sibley1, M. Signorelli1, R.J. Smith1 , M. Slepchenkov1, G. Snitchler1, J.B. Titus1, J. Ufnal1, Paper T. Valentine1, W. Waggoner1, J.K. Walters1, C. Weixel1, M. Wollenberg1, S. Ziaei1, L. Schmitz2, Z. Lin3, A.A. Ivanov4, T. Asai5 , E.A. Baltz6, 6 1 1741-4326 J.C. Platt and the TAE Team 1 TAE Technologies, Inc., Foothill Ranch, CA, United States of America 2 University of California at Los Angeles, Los Angeles, CA, United States of America 3 11 University of California at Irvine, Irvine, CA, United States of America 4 Budker Institute of Nuclear Physics, Novosibirsk, Russian Federation 5 Nihon University, Tokyo, Japan 6 Google LLC, Mountain View, CA, United States of America E-mail: [email protected] Received 23 November 2018, revised 8 February 2019 Accepted for publication 1 March 2019 Published 5 June 2019 Abstract TAE Technologies’ research is devoted to producing high temperature, stable, long-lived field-reversed configuration (FRC) plasmas by neutral-beam injection (NBI) and edge biasing/control. The newly constructed C-2W experimental device (also called ‘Norman’) is the world’s largest compact-toroid (CT) device, which has several key upgrades from the preceding C-2U device such as higher input power and longer pulse duration of the NBI system as well as installation of inner divertors with upgraded electrode biasing systems. Initial C-2W experiments have successfully demonstrated a robust FRC formation and its translation into the confinement vessel through the newly installed inner divertor with adequate guide magnetic field. They also produced dramatically improved initial FRC states with higher plasma temperatures (Te ~ 250 + eV; total electron and ion temperature >1.5 keV, based on pressure balance) and more trapped flux (up to ~15 mWb, based on rigid-rotor model) inside the FRC immediately after the merger of collided two CTs in the confinement section. As for effective edge control on FRC stabilization, a number of edge biasing schemes 1741-4326/19/112009+16$33.00 1 © 2019 IAEA, Vienna Printed in the UK Nucl. Fusion 59 (2019) 112009 H. Gota et al have been tried via open field-lines, in which concentric electrodes located in both inner and outer divertors as well as end-on plasma guns are electrically biased independently. As a result of effective outer-divertor electrode biasing alone, FRC plasma is well stabilized and diamagnetism duration has reached up to ~9 ms which is equivalent to C-2U plasma duration. Magnetic field flaring/expansion in both inner and outer divertors plays an important role in creating a thermal insulation on open field-lines to reduce a loss rate of electrons, which leads to improvement of the edge and core FRC confinement properties. An experimental campaign with inner-divertor magnetic-field flaring has just commenced and early result indicates that electron temperature of the merged FRC stays relatively high and increases for a short period of time, presumably by NBI and E × B heating. Keywords: field-reversed configuration, compact toroid, neutral beam injection, edge control, collisional merging (Some figures may appear in colour only in the online journal) 1. Introduction to be absent or strongly suppressed in the plasma core, mainly due to the large FRC ion orbits (finite Larmor radius effect A field-reversed configuration (FRC) is a prolate, high-beta [11]), resulting in near-classical thermal ion confinement compact toroid (CT) that has closed magnetic field-lines inside [10, 12]. In order to further improve HPF plasma parameters, the separatrix and open field-line regions of poloidal axisym- the C-2U experimental program commenced after various metric magnetic field with zero or small self-generated toroidal key system upgrades from C-2, including increased total NB magnetic field [1, 2]. The FRC topology is generated by the input power from ~4 MW (20 keV hydrogen) to ~10 + MW plasma’s own diamagnetic currents, of sufficient strength to (15 keV hydrogen, higher current at reduced beam energy) reverse the exterior magnetic field, and the FRC only requires with tilted injection angle, and enhanced edge biasing capa- external solenoidal coils to hold the structure inside a confine- bility for boundary/stability control. The upgraded NBI and ment vessel (CV). The plasma current typically decays away edge biasing systems enabled significant plasma performance in a resistive timescale but can be maintained by a current advances and had a profound impact on C-2U performance drive such as neutral beam (NB) injection (NBI). The averaged such as: (i) rapid accumulation of fast ions (about half of beta value of FRCs is near unity: β = 2µ p /B2 90%, the initial thermal pressure replaced by fast-ion pressure); 0 e ∼ where μ0 is the permeability of free space, p is the average (ii) fast-ion footprint largely determines FRC dimensions; plasma pressure, and Be is the external magnetic field. The (iii) double-humped electron density and temperature pro- edge layer outside of the FRC separatrix coalesces into axial files (indicative of substantial fast-ion pressure) [13, 14]; (iv) jets beyond each end of the FRC, providing a natural divertor, FRC lifetime and global plasma stability scale strongly with which may allow extraction of energy without restriction via NB input power; and (v) plasma performance correlates with direct energy conversion. The FRC has potential for a fusion NB pulse duration in which diamagnetism persists several reactor with low-cost construction and minimal maintenance milliseconds after NB termination due to accumulated fast due to its simple geometry. FRCs may also allow the use of ions. Therefore, this improved plasma state created via effec- advanced, aneutronic fuels such as D-3He and p-11B. tive NBI is called a beam-driven FRC. Under the optimum In the past C-2 [3, 4] and C-2U [5, 6] FRC experiments C-2U operating conditions, plasma sustainment for ~5 + ms, at TAE Technologies, studying FRC behavior, as well as as well as long-lived decaying plasma discharges of up to demonstration of the FRC plasma sustainment by NBI and 10 + ms, were successfully achieved [6] and performance edge biasing/control, were the primary goals. One of the key was mostly limited by hardware and stored energy constraints accomplishments in the C-2 experiments was demonstration/ such as the NB’s pulse duration and the current sourcing capa- creation of the high-performance FRC (HPF) regime, which bility of the end-on plasma guns. Furthermore, with careful was set apart by dramatic improvements in confinement and 0D global power-balance analysis [15, 16], there appeared to stability compared to other past FRC devices [4, 7–10]. HPF be a strong positive correlation between electron temperature plasma discharges have also demonstrated increasing plasma Te and energy confinement time; i.e. the electron energy con- pressure and electron temperature Te, indicating an accumula- finement timeτ E,e in C-2U FRC discharges scales strongly tion of fast ions as well as plasma heating by NBI. Electrically with a positive power of Te [6, 16], which is basically the biased end-on plasma guns and effective wall/surface con- same characteristics/trend as observed in C-2 [4]. This posi- ditioning inside the vacuum vessel also played important tive confinement scaling is very attractive, and similar features roles in producing HPF plasmas, synergistically with NBI. of temperature dependence have also been observed in other The HPF plasmas are macroscopically stable and microsta- high-beta devices such as NSTX [17, 18] and MAST [19], bility properties appear to be different from typical regimes in whereby the energy confinement time scales nearly inversely toroidal confinement devices. Ion-scale fluctuations are found with collisionality. 2 Nucl. Fusion 59 (2019) 112009 H. Gota et al In order to further improve FRC performance as well as open-field-line plasmas. Table 1 lists key machine settings/ to overcome engineering constraints mentioned above, the parameters as well as functionalities in those various operating C-2U device has been again upgraded to C-2W (also called phases to briefly summarize which subsystems are required or ‘Norman’, shown in figure 1). Substantial facility changes can be used for experiments. have taken place, in which the C-2U device was completely In the paper, the C-2W experimental apparatus and plasma dismantled and the brand-new experimental device C-2W diagnostic suite including newly-upgraded/developed subsys- was constructed within one year.
Load more

Recommended publications
  • Aspects of Advanced Fuel FRC Fusion Reactors
    Aspects of Advanced Fuel FRC Fusion Reactors John F Santarius and Gerald L Kulcinski Fusion Technology Institute Engineering Physics Department CT2016 Irvine, California August 22-24, 2016 [email protected]; 608-692-4128 Laundry List of Fusion Reactor Development Issues • Plasma physics of fusion fuel cycles • Engineering issues unique or more ! Cross sections and Maxwellian reactivity important for DT fuel ! Beta and B-field utilization ! Tritium-breeding blanket design ! Plasma fusion power density ! Neutron damage to materials ! Plasma energy and particle confinement ! Radiological hazard (afterheat and waste disposal) ! Neutron production vs Ti for various fuel ion ratios • Safety • Geometry implications for engineering design • Environment ! Power flows • Licensing ! Direct energy conversion ! Magnet configuration • Economics ! Radiation shielding ! Maintenance in a highly radioactive environment • Nuclear non-proliferation ! Coolant piping accessibility • Non‑electric applications • Plasma‑surface interactions • 3He fuel supply JFS 2016 Fusion Technology Institute, University of Wisconsin 2 UW Developed and/or Participated in 40 MFE & 26 IFE Power Plant and Test Facility Studies in Past 46 years MFE-40 IFE-26 JFS 2016 Fusion Technology Institute, University of Wisconsin 3 Total Fusion Reactivities for Key Fusion Fuels Total Energy Production Rate st 1 generation fuels: MaxwellianTotal Reactivities -19 D + T → n (14.07 MeV) + 4He (3.52 MeV) 10 D + D → n (2.45 MeV) + 3He (0.82 MeV) → p (3.02 MeV) + T (1.01 MeV) -20 {50% each
    [Show full text]
  • Thermonuclear AB-Reactors for Aerospace
    1 Article Micro Thermonuclear Reactor after Ct 9 18 06 AIAA-2006-8104 Micro -Thermonuclear AB-Reactors for Aerospace* Alexander Bolonkin C&R, 1310 Avenue R, #F-6, Brooklyn, NY 11229, USA T/F 718-339-4563, [email protected], [email protected], http://Bolonkin.narod.ru Abstract About fifty years ago, scientists conducted R&D of a thermonuclear reactor that promises a true revolution in the energy industry and, especially, in aerospace. Using such a reactor, aircraft could undertake flights of very long distance and for extended periods and that, of course, decreases a significant cost of aerial transportation, allowing the saving of ever-more expensive imported oil-based fuels. (As of mid-2006, the USA’s DoD has a program to make aircraft fuel from domestic natural gas sources.) The temperature and pressure required for any particular fuel to fuse is known as the Lawson criterion L. Lawson criterion relates to plasma production temperature, plasma density and time. The thermonuclear reaction is realised when L > 1014. There are two main methods of nuclear fusion: inertial confinement fusion (ICF) and magnetic confinement fusion (MCF). Existing thermonuclear reactors are very complex, expensive, large, and heavy. They cannot achieve the Lawson criterion. The author offers several innovations that he first suggested publicly early in 1983 for the AB multi- reflex engine, space propulsion, getting energy from plasma, etc. (see: A. Bolonkin, Non-Rocket Space Launch and Flight, Elsevier, London, 2006, Chapters 12, 3A). It is the micro-thermonuclear AB- Reactors. That is new micro-thermonuclear reactor with very small fuel pellet that uses plasma confinement generated by multi-reflection of laser beam or its own magnetic field.
    [Show full text]
  • LA-8700-C N O Proceedings of the Third Symposium on the Physics
    LA-8700-C n Conference Proceedings of the Third Symposium on the Physics and Technology of Compact Toroids in the Magnetic Fusion Energy Program Held at the Los Alamos National Laboratory Los Alamos, New Mexico December 2—4, 1980 c "(0 O a> 9 n& anna t LOS ALAMOS SCIENTIFIC LABORATORY Post Office Box 1663 Los Alamos. New Mexico 87545 An Affirmative Aution/f-qual Opportunity Fmployei This report was not edited by the Technical Information staff. This work was supported by the US Depart- ment of Energy, Office of Fusion Energy. DISCLAIM) R This report WJJ prepared as jn JLUOUIH of work sponsored by jn agency of ihc Untied Slates (.ovcrn- rneni Neither the United Suit's (iovci.iment nor anv a^cmy thereof, nor any HI theu employees, makes Jn> warranty, express or in,Hied, o( assumes any legal liability 01 responsibility for the jn-ur- aty. completeness, or usefulness of any information, apparatus, product, 01 process disiiosed, or rep- resents thai its use would not infringe privately owned rights. Reference herein to any specifu- com- mercial product process, or service by tradr name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommcniidlK>n, or favoring by the United Stales Government or any agency thereof. The views and opinions of authors expressed herein do not nec- essarily state 01 reflect those nf llic United Stales Government or any agency thereof. UfJITED STATES DEPARTMENT OF ENERGY CONTRACT W-7405-ENG. 36 LA-8700-C Conference UC-20 issued: March 1981 Proceedings of the Third Symposium on the Physics and Technology of Compact Toroids in the Magnetic Fusion Energy Program Heki at the Los Alamos National Laboratory Los Alamos, New Mexico Decamber 2—4, 1980 Compiled by Richard E.
    [Show full text]
  • Analysis of Equilibrium and Topology of Tokamak Plasmas
    ANALYSIS OF EQUILIBRIUM AND TOPOLOGY OF TOKAMAK PLASMAS Boudewijn Philip van Millig ANALYSIS OF EQUILIBRIUM AND TOPOLOGY OF TOKAMAK PLASMAS BOUDEWHN PHILIP VAN MILUGEN Cover picture: Frequency analysis of the signal of a magnetic pick-up coil. Frequency increases upward and time increases towards the right. Bright colours indicate high spectral power. An MHD mode is seen whose frequency decreases prior to a disruption (see Chapter 5). II ANALYSIS OF EQUILIBRIUM AND TOPOLOGY OF TOKAMAK PLASMAS ANALYSE VAN EVENWICHT EN TOPOLOGIE VAN TOKAMAK PLASMAS (MET EEN SAMENVATTING IN HET NEDERLANDS) PROEFSCHRIFT TER VERKRUGING VAN DE GRAAD VAN DOCTOR IN DE WISKUNDE EN NATUURWETENSCHAPPEN AAN DE RUKSUNIVERSITEIT TE UTRECHT, OP GEZAG VAN DE RECTOR MAGNIFICUS PROF. DR. J.A. VAN GINKEL, VOLGENS BESLUTT VAN HET COLLEGE VAN DECANEN IN HET OPENBAAR TE VERDEDIGEN OP WOENSDAG 20 NOVEMBER 1991 DES NAMIDDAGS TE 2.30 UUR DOOR BOUDEWUN PHILIP VAN MILLIGEN GEBOREN OP 25 AUGUSTUS 1964 TE VUGHT DRUKKERU ELINKWIJK - UTRECHT m PROMOTOR: PROF. DR. F.C. SCHULLER CO-PROMOTOR: DR. N.J. LOPES CARDOZO The work described in this thesis was performed as part of the research programme of the 'Stichting voor Fundamenteel Onderzoek der Materie' (FOM) with financial support from the 'Nederlandse Organisatie voor Wetenschappelijk Onderzoek' (NWO) and EURATOM, and was carried out at the FOM-Instituut voor Plasmafysica te Nieuwegein, the Max-Planck-Institut fur Plasmaphysik, Garching bei Munchen, Deutschland, and the JET Joint Undertaking, Abingdon, United Kingdom. IV iEstos Bretones
    [Show full text]
  • Alternative Fusion Reactors As Future Commercial Power Plants
    J. Plasma Fusion Res. SERIES, Vol. 8 (2009) Alternative Fusion Reactors as Future Commercial Power Plants Sergei V. RYZHKOV Bauman Moscow State Technical University (Received: 29 August 2008 / Accepted: 1 April 2009) Alternative reactor based on a field-reversed configuration (FRC) has advantages of the cylindrical geometry, the open field line geometry (direct energy conversion (DEC) of the charged-particle flow), and high � (plasma pressure/magnetic-field pressure). This paper aims to evaluate the attractiveness of a low radioactive FRC fusion core. Analysis of a conceptual deuterium - helium-3 (D-3He) fusion power reactor is presented and reference point is defined. Principal parameters of the D-3He plasma reference case (RC) and comparison with conceptual D-3He tokamak and FRC power plants are shown. Keywords: advanced fuel, alternative concept, aneutronic reactions, bremsstrahlung, compact toroid, field reversed configuration, low radioactive reactor, magnetic confinement. 1. Introduction The main advantage of RMF is that as plasma The FRC [1,2] is a confinement device (FRC plasma shaping or ion beams RMF would be needed for stability. Various plasma parameters are given in [5] for RMF is a toroid with the exclusively poloidal magnetic field) combining of properties and prospects of the open and formed plasmas and theta-pinch formed plasmas. closed magnetic system and leading to very large reactor Appropriate hot, steady-state FRCs can now be formed using RMF and scaling laws developed for achievable advantages (see Fig. 1). Actually, FRC experiment was started in Russia (TRINITI) and USA (LANL) in 1970s. RMF sustained FRC flux levels [6]. Review papers have been published in the 1980s [3,4].
    [Show full text]
  • NIAC 2011 Phase I Tarditti Aneutronic Fusion Spacecraft Architecture Final Report
    NASA-NIAC 2001 PHASE I RESEARCH GRANT on “Aneutronic Fusion Spacecraft Architecture” Final Research Activity Report (SEPTEMBER 2012) P.I.: Alfonso G. Tarditi1 Collaborators: John H. Scott2, George H. Miley3 1Dept. of Physics, University of Houston – Clear Lake, Houston, TX 2NASA Johnson Space Center, Houston, TX 3University of Illinois-Urbana-Champaign, Urbana, IL Executive Summary - Motivation This study was developed because the recognized need of defining of a new spacecraft architecture suitable for aneutronic fusion and featuring game-changing space travel capabilities. The core of this architecture is the definition of a new kind of fusion-based space propulsion system. This research is not about exploring a new fusion energy concept, it actually assumes the availability of an aneutronic fusion energy reactor. The focus is on providing the best (most efficient) utilization of fusion energy for propulsion purposes. The rationale is that without a proper architecture design even the utilization of a fusion reactor as a prime energy source for spacecraft propulsion is not going to provide the required performances for achieving a substantial change of current space travel capabilities. - Highlights of Research Results This NIAC Phase I study provided led to several findings that provide the foundation for further research leading to a higher TRL: first a quantitative analysis of the intrinsic limitations of a propulsion system that utilizes aneutronic fusion products directly as the exhaust jet for achieving propulsion was carried on. Then, as a natural continuation, a new beam conditioning process for the fusion products was devised to produce an exhaust jet with the required characteristics (both thrust and specific impulse) for the optimal propulsion performances (in essence, an energy-to-thrust direct conversion).
    [Show full text]
  • Plasma Stability and the Bohr - Van Leeuwen Theorem
    NASA TECHNICAL NOTE -I m 0 I iii I nE' n z c * v) 4 z PLASMA STABILITY AND THE BOHR - VAN LEEUWEN THEOREM by J. Reece Roth Lewis Research Center Cleueland, Ohio NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON, D. C. APRIL 1967 I ~ .. .. .. TECH LIBRARY KAFB, NM I llllll Illlll lull IIM IIllIll1 Ill1 OL3060b NASA TN D-3880 PLASMA STABILITY AND THE BOHR - VAN LEEWEN THEOREM By J. Reece Roth Lewis Research Center Cleveland, Ohio NATIONAL AERONAUTICS AND SPACE ADMINISTRATION For sale by the Clearinghouse for Federal Scientific and Technical Information Springfield, Virginia 22151 - CFSTI price $3.00 CONTENTS Page SUMMARY.- ........................................ 1 INTRODUCTION-___ ..................................... 2 THE BOHR - VAN LEEUWEN THEOREM ....................... 3 RELATION OF THE BOHR - VAN LEEUWEN THEOREM TO CONVENTIONAL MACROSCOPIC THEORIES OF PLASMA STABILITY ................ 3 The Momentum Equation .............................. 3 The Conventional Magnetostatic and Hydromagnetic Theories .......... 4 The Bohr - van Leeuwen Theorem. ........................ 7 Application of the Bohr - van Leeuwen Theorem to Plasmas ........... 9 The Bohr - van Leeuwen Theorem and the Literature of Plasma Physics .... 10 PLASMA CURRENTS ................................. 11 Assumptions of Analysis .............................. 11 Sources of Plasma Currents ............................ 12 Net Plasma Currents. ............................... 15 CHARACTERISTICS OF PLASMAS SATISFYING THE BOHR - VAN LEEUWEN THEOREM .....................................
    [Show full text]
  • 1. Introduction 2. the ROSE Code
    M. Drevlak et al. New results in stellarator optimisation M. Drevlak , C. D. Beidler, J. Geiger, P. Helander, S. Henneberg, C. N¨uhrenberg, Y. Turkin Max-Planck-Institut f¨ur Plasmaphysik, 17491 Greifswald, Germany Email: [email protected] Abstract The ROSE code was written for the optimisation of stellarator equilibria. It uses VMEC for the equilibrium calculation and several different optimising algorithms for adjusting the boundary coefficients of the plasma. Some of the most important capabilities include optimisation for simple coils, the ability to simultaneously optimise vacuum and finite beta field, direct analysis of particle drift orbits and direct shaping of the magnetic field structure. ROSE was used to optimise quasi- isodynamic, quasi-axially symmetric and quasi-helically symmetric stellarator configurations. 1. Introduction The performance of stellarators, characterised by properties related to MHD stability, confinement of fast particles, neoclassical and anomalous transport and engineering complexity, is known to depend strongly on the underlying equilibrium configuration. While the first fully optimised stellarators, HSX and Wendelstein 7-X, have entered operation, new stellarator designs are being considered. In particular, a possible stellarator reactor needs to be optimised beyond the optimisation level achieved for these devices. A strong need for progress has been identified in the confinement of fast particles significantly away from the magnetic axis. At the same time, coil complexity must not exceed the limits of feasibility. 2. The ROSE Code The ROSE [1] code was written for the optimi- VMEC Equilibrium field sation of stellarator equilibria. Like other tools Brents algorithm created for the optimisation of stellarator equilib- Parallel Line−Search VM2MAG B spectrum ria [2] [3], it uses VMEC [4] for the equilibrium Genetic Optimisation mn calculation and several different optimising algo- Harmony Search SURFGEN, Coil complexity rithms for adjusting the coefficients of the bound- Particle Swarm NESCOIL ary shape of the plasma.
    [Show full text]
  • 1 Looking Back at Half a Century of Fusion Research Association Euratom-CEA, Centre De
    Looking Back at Half a Century of Fusion Research P. STOTT Association Euratom-CEA, Centre de Cadarache, 13108 Saint Paul lez Durance, France. This article gives a short overview of the origins of nuclear fusion and of its development as a potential source of terrestrial energy. 1 Introduction A hundred years ago, at the dawn of the twentieth century, physicists did not understand the source of the Sun‘s energy. Although classical physics had made major advances during the nineteenth century and many people thought that there was little of the physical sciences left to be discovered, they could not explain how the Sun could continue to radiate energy, apparently indefinitely. The law of energy conservation required that there must be an internal energy source equal to that radiated from the Sun‘s surface but the only substantial sources of energy known at that time were wood or coal. The mass of the Sun and the rate at which it radiated energy were known and it was easy to show that if the Sun had started off as a solid lump of coal it would have burnt out in a few thousand years. It was clear that this was much too shortœœthe Sun had to be older than the Earth and, although there was much controversy about the age of the Earth, it was clear that it had to be older than a few thousand years. The realization that the source of energy in the Sun and stars is due to nuclear fusion followed three main steps in the development of science.
    [Show full text]
  • Modeling and Control of Plasma Rotation for NSTX Using
    PAPER Related content - Central safety factor and N control on Modeling and control of plasma rotation for NSTX NSTX-U via beam power and plasma boundary shape modification, using TRANSP for closed loop simulations using neoclassical toroidal viscosity and neutral M.D. Boyer, R. Andre, D.A. Gates et al. beam injection - Topical Review M S Chu and M Okabayashi To cite this article: I.R. Goumiri et al 2016 Nucl. Fusion 56 036023 - Rotation and momentum transport in tokamaks and helical systems K. Ida and J.E. Rice View the article online for updates and enhancements. Recent citations - Design and simulation of the snowflake divertor control for NSTX–U P J Vail et al - Real-time capable modeling of neutral beam injection on NSTX-U using neural networks M.D. Boyer et al - Resistive wall mode physics and control challenges in JT-60SA high scenarios L. Pigatto et al This content was downloaded from IP address 128.112.165.144 on 09/09/2019 at 19:26 IOP Nuclear Fusion International Atomic Energy Agency Nuclear Fusion Nucl. Fusion Nucl. Fusion 56 (2016) 036023 (14pp) doi:10.1088/0029-5515/56/3/036023 56 Modeling and control of plasma rotation for 2016 NSTX using neoclassical toroidal viscosity © 2016 IAEA, Vienna and neutral beam injection NUFUAU I.R. Goumiri1, C.W. Rowley1, S.A. Sabbagh2, D.A. Gates3, S.P. Gerhardt3, M.D. Boyer3, R. Andre3, E. Kolemen3 and K. Taira4 036023 1 Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA I.R. Goumiri et al 2 Department of Applied Physics and Applied Mathematics,
    [Show full text]
  • An Overview of the HIT-SI Research Program and Its Implications for Magnetic Fusion Energy
    An overview of the HIT-SI research program and its implications for magnetic fusion energy Derek Sutherland, Tom Jarboe, and The HIT-SI Research Group University of Washington 36th Annual Fusion Power Associates Meeting – Strategies to Fusion Power December 16-17, 2015, Washington, D.C. Motivation • Spheromaks configurations are attractive for fusion power applications. • Previous spheromak experiments relied on coaxial helicity injection, which precluded good confinement during sustainment. • Fully inductive, non-axisymmetric helicity injection may allow us to overcome the limitations of past spheromak experiments. • Promising experimental results and an attractive reactor vision motivate continued exploration of this possible path to fusion power. Outline • Coaxial helicity injection NSTX and SSPX • Overview of the HIT-SI experiment • Motivating experimental results • Leading theoretical explanation • Reactor vision and comparisons • Conclusions and next steps Coaxial helicity injection (CHI) has been used successfully on NSTX to aid in non-inductive startup Figures: Raman, R., et al., Nucl. Fusion 53 (2013) 073017 • Reducing the need for inductive flux swing in an ST is important due to central solenoid flux-swing limitations. • Biasing the lower divertor plates with ambient magnetic field from coil sets in NSTX allows for the injection of magnetic helicity. • A ST plasma configuration is formed via CHI that is then augmented with other current drive methods to reach desired operating point, reducing or eliminating the need for a central solenoid. • Demonstrated on HIT-II at the University of Washington and successfully scaled to NSTX. Though CHI is useful on startup in NSTX, Cowling’s theorem removes the possibility of a steady-state, axisymmetric dynamo of interest for reactor applications • Cowling* argued that it is impossible to have a steady-state axisymmetric MHD dynamo (sustain current on magnetic axis against resistive dissipation).
    [Show full text]
  • Stellarator and Tokamak Plasmas: a Comparison
    Home Search Collections Journals About Contact us My IOPscience Stellarator and tokamak plasmas: a comparison This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2012 Plasma Phys. Control. Fusion 54 124009 (http://iopscience.iop.org/0741-3335/54/12/124009) View the table of contents for this issue, or go to the journal homepage for more Download details: IP Address: 130.183.100.97 The article was downloaded on 22/11/2012 at 08:08 Please note that terms and conditions apply. IOP PUBLISHING PLASMA PHYSICS AND CONTROLLED FUSION Plasma Phys. Control. Fusion 54 (2012) 124009 (12pp) doi:10.1088/0741-3335/54/12/124009 Stellarator and tokamak plasmas: a comparison P Helander, C D Beidler, T M Bird, M Drevlak, Y Feng, R Hatzky, F Jenko, R Kleiber,JHEProll, Yu Turkin and P Xanthopoulos Max-Planck-Institut fur¨ Plasmaphysik, Greifswald and Garching, Germany Received 22 June 2012, in final form 30 August 2012 Published 21 November 2012 Online at stacks.iop.org/PPCF/54/124009 Abstract An overview is given of physics differences between stellarators and tokamaks, including magnetohydrodynamic equilibrium, stability, fast-ion physics, plasma rotation, neoclassical and turbulent transport and edge physics. Regarding microinstabilities, it is shown that the ordinary, collisionless trapped-electron mode is stable in large parts of parameter space in stellarators that have been designed so that the parallel adiabatic invariant decreases with radius. Also, the first global, electromagnetic, gyrokinetic stability calculations performed for Wendelstein 7-X suggest that kinetic ballooning modes are more stable than in a typical tokamak.
    [Show full text]