A5071137271- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Laser-Plasma Interactions and Diagnostics
- Solar and Space Plasma Dynamics
- Korean Peninsula Historical and Political Studies
- Nuclear reactor physics and engineering
- Quantum chaos and dynamical systems
- Physics of Superconductivity and Magnetism
- Atomic and Subatomic Physics Research
- Vacuum and Plasma Arcs
- Dust and Plasma Wave Phenomena
- Engineering and Environmental Studies
- Astro and Planetary Science
- Nuclear and radioactivity studies
- Geomagnetism and Paleomagnetism Studies
- Laser-induced spectroscopy and plasma
- Nuclear Materials and Properties
- Plasma and Flow Control in Aerodynamics
- Magnetic Field Sensors Techniques
- Graphite, nuclear technology, radiation studies
- Rare-earth and actinide compounds
Princeton Plasma Physics Laboratory
2008-2024
Princeton University
2008-2024
Fusion (United States)
2016-2024
University of Helsinki
2019-2024
Fusion Academy
2023
Lithium Power (United States)
2021
Helsinki Institute of Physics
2021
Moscow Engineering Physics Institute
2019-2020
Bryansk State Technical University
2016-2020
Plasma (Russia)
1992-2019
As part of the ITER Design Review and in response to issues identified by Science Technology Advisory Committee, physics requirements were reviewed as appropriate updated. The focus this paper will be on recent work affecting design with special emphasis topics near-term procurement arrangements. This describe results on: sensitivity studies, poloidal field coil requirements, vertical stability, effect toroidal ripple thermal confinement, material choice heat load for plasma-facing...
National Spherical Torus Experiment [which M. Ono et al., Nucl. Fusion 40, 557 (2000)] high-power divertor plasma experiments have shown, for the first time, that benefits from lithium coatings applied to facing components found previously in limited plasmas can occur also diverted configurations. Lithium were with pellets injected into helium discharges, and an oven directed a collimated stream of vapor toward graphite tiles lower center stack divertor. depositions few milligrams 1g been...
Extensive lithium wall coatings and liquid plasma-limiting surfaces reduce recycling, with dramatic improvements in Ohmic plasma discharges the Current Drive Experiment-Upgrade. Global energy confinement times increase by up to 6 times. These results exceed scalings such as $\mathrm{ITER}98\mathrm{P}(y,1)$ $2--3$ times, represent largest ever observed for an tokamak plasma. Measurements of ${D}_{\ensuremath{\alpha}}$ emission indicate that global recycling coefficients decrease approximately...
Experiments in the National Spherical Torus Experiment (NSTX) have shown beneficial effects on performance of divertor plasmas as a result applying lithium coatings graphite and carbon-fiber-composite plasma-facing components. These mostly been applied by pair evaporators mounted at top vacuum vessel which inject collimated streams vapor toward lower divertor. In neutral beam injection (NBI)-heated deuterium H-mode run immediately after application lithium, modifications included decreases...
This paper describes progress achieved since 2007 in understanding disruptions tokamaks, when the effect of plasma current sharing with wall was introduced into theory. As a result, toroidal asymmetry measurements during vertical disruption event (VDE) on Joint European Torus explained. A new kind equilibria and mode coupling theory, which can explain duration external kink 1/1 VDE. The presents first results numerical simulations using free boundary model, relevant to disruptions.
Abstract As an alternative choice of solid plasma facing components (PFCs), flowing liquid lithium can serve as a limiter or divertor PFC and offers self-healing surface with acceptable heat removal good impurity control. Such system could improve performance, therefore be attractive for future fusion devices. Recently, continuously (FLiLi) has been successfully designed tested in the EAST superconducting tokamak. A circulating layer thickness <0.1 mm flow rate ~2 cm 3 s −1 was achieved....
We report the first observation of global recycling coefficient R near 0.5 in Lithium Tokamak eXperiment-β (LTX-β), significantly below minimum previously reported other devices. In a series experiments with varied Li wall conditioning, estimates have been made using Lyman-α array and DEGAS2 modeling. A progressive reduction emission increased lithium an increase edge electron temperature are observed. It is also observed that increasing coating thickness, effective particle confinement time...
Recent experiments in the Current Drive Experiment-Upgrade (CDX-U) provide a first-ever test of large area liquid lithium surfaces as tokamak first wall to gain engineering experience with metal and investigate whether very low recycling plasma regimes can be accessed walls. The CDX-U is compact (R = 34 cm, 22 Btoroidal 2 kG, IP 100 kA, Te(0)∼ eV, ne(0) ∼ 5 × 1019 m−3) spherical torus at Princeton Plasma Physics Laboratory. A toroidal pool limiter an 2000 cm2 (half total limiting surface)...
Reductions in H content and particle recycling are important for the improvement of ion cyclotron range frequency (ICRF) minority heating efficiency enhancement plasma performance EAST superconducting tokamak. During recent years several techniques surface conditioning such as baking, glow discharge cleaning/ICRF cleaning, coatings, boronization, siliconization lithium coating, have all been attempted order to reduce H/(H+D) ratio EAST. Even though boronization were both reasonably effective...
A key feature of disruptions during vertical displacement events, discovered in JET 1996, is the toroidal variation measured plasma current Ip, i.e. asymmetries, lasting for almost entire quench. The unique magnetic diagnostics at (full set poloidal coils and saddle loops recorded either from two toroidally opposite or four orthogonal locations) allow a comprehensive analysis asymmetrical with large scale database. This paper presents an 4854 over 18 year period that includes both carbon (C)...
It is shown that lithium walls resulting in zero-recycling regimes at the edge of magnetic fusion device can cause dramatic improvements core plasma performance. The temperature wall these much larger than conventional tokamaks. reduces gradient and, thus, related anomalous transport, allowing an increase achievable beta to level ∼20%, due stabilization and second stability core. Fusion relevant over entire high results a strong enhancement power density. Modeling International Thermonuclear...
The two-fluid linear magnetohydrodynamic (MHD) theory of the internal kink mode is studied in finite β regimes relevant to recent high-temperature tokamak experiments. It found that scale length plasma motion decouples due Hall term from current layer and becomes ‘‘ion-sound Larmor radius’’ ρs=cs/Ωci, where cs=√(Te+γiTi)/mi ion-sound speed (γi=5/3 for adiabatic ions), Ωci ion-cyclotron frequency. predictions MHD m=1 reconnection are shown be good quantitative agreement with analogous results...
This paper explains the existence of m∕n=1∕1 kink mode during vertical disruption event when plasma has an electrical contact with facing conducting surfaces. It is shown that perturbation can be in equilibrium state even a stable safety factor q&gt;1, if surface currents, excited by mode, flow through structure. The present theory suggests explanation so-called sideway forces on tokamak in-vessel components event. For general case such wall touching modes, energy principle derived,...
Two different types of flowing liquid lithium limiters were firstly installed and successfully tested in HT-7 tokamaks 2012 some encouraging results obtained. the first type, called FLiLi limiters, used a thin layer under gravity. The other type had lithium-metal infused trenches (LIMIT) for thermoelectric magnetohydrodynamic drive metal flow. surface one was coated by evaporated before injected Ar pressure into special distributor limiter. Then could slowly move along plasma facing guide...
Asymmetrical disruptions may occur during ITER operation and they be accompanied by large sideways forces rotation of the asymmetry. This is particular concern because resonance rotating asymmetry with natural frequencies vacuum vessel (and other in-vessel components) could lead to dynamic amplification forces. A significant fraction non-mitigated JET have toroidally asymmetric currents that flow partially inside plasma surrounding ('wall'). The toroidal asymmetries (otherwise known as...