Results 11 to 20 of about 302,060 (167)

Gyrokinetic simulations of spherical tokamaks [PDF]

Plasma Physics and Controlled Fusion, 2009
This paper reviews transport and confinement in spherical tokamaks (STs) and our current physics understanding of this that is partly based on gyrokinetic simulations. Equilibrium flow shear plays an important role, and we show how this is consistently included in the gyrokinetic framework for flows that greatly exceed the diamagnetic velocity. The key
Roach, C, Abel, I, Akers, R, Arter, W, Barnes, M, Camenen, Y, Casson, F, Colyer, G, Connor, J, Cowley, S, Dickinson, D, Dorland, W, Field, A, Guttenfelder, W, Hammett, G, Hastie, R, Highcock, E, Loureiro, N, Peeters, A, Reshko, M, Saarelma, S, Schekochihin, A, Valovic, M, Wilson, H   +23 more
openaire   +3 more sources

Applications of fast wave in spherical tokamaks [PDF]

AIP Conference Proceedings, 1997
In spherical tokamaks (ST), the magnetic field strength varies over a wide range across the plasma, and at high betas it deviates significantly from the 1/R dependence of conventional tokamaks. This, together with the high density expected in ST, poses challenging problems for RF heating and current drive.
Chiu, S. C., Chan, V. S., Lin-Liu, Y. R., Miller, R. L., Prater, R., Politzer, P.   +5 more
openaire   +3 more sources

Reducing turbulent transport in tokamaks by combining intrinsic rotation and the low momentum diffusivity regime

Nuclear Fusion
Based on the analysis of a large number of high-fidelity nonlinear gyrokinetic simulations, we propose a novel strategy to improve confinement in spherical tokamak plasmas by combining up-down asymmetric flux surface shaping with the Low Momentum ...
Haomin Sun, Justin Ball, Stephan Brunner, Anthony Field, Bhavin Patel, Daniel Kennedy, Colin Roach, Diego Jose Cruz-Zabala, Fernando Puentes Del Pozo, Eleonora Viezzer, Manuel Garcia Munoz   +10 more
doaj   +3 more sources

Plasma self-driven current in tokamaks with magnetic islands

Nuclear Fusion
Magnetic island perturbations may cause a reduction in plasma self-driven current that is needed for tokamak operation. A novel effect on tokamak self-driven current revealed by global gyrokinetic simulations is due to magnetic-island-induced 3D electric
W.X. Wang, M.G. Yoo, E.A. Startsev, S. Kaye, S. Ethier, J. Chen   +5 more
doaj   +2 more sources

L-H transition studies on spherical tokamaks [PDF]

, 2023
While the higher fusion power achieved in high confinement (H-)mode make it a desirable regime for tokamak devices, the transition from low confinement (L-)mode to H-mode is a complex, multi-faceted process whose dynamics are still not fully understood ...
Howlett, Lena
core   +2 more sources

Runaway dynamics in reactor-scale spherical tokamak disruptions [PDF]

, 2022
Understanding generation and mitigation of runaway electrons in disruptions is important for the safe operation of future tokamaks. In this paper we investigate runaway dynamics in reactor-scale spherical tokamaks.
Vallhagen, Oskar, Pusztai, I., Berger, Esm\ue9e, Newton, Sarah, Vallhagen, O., Fülöp, T., Berger, E., Newton, S. L., F\ufcl\uf6p, T\ufcnde-Maria, Pusztai, Istvan, Hoppe, M., Fil, A., Vallhagen, Oskar,, Fil, A.,, Newton, Sarah,, Berger, Esmee, Hoppe, Mathias, Pusztai, Istvan,, Fulop, Tunde, Fülöp, Tünde-Maria,, Fil, Alexandre, Newton, Sarah L., Berger, Esmée,, Hoppe, M.,   +23 more
core   +3 more sources

Plasma Physics Regimes in Tokamaks with Li Walls [PDF]

, 2003
Low recycling regimes with a plasma limited by a lithium wall surface suggest enhanced stability and energy confinement, both necessary for tokamak reactors. These regimes could make ignition feasible in compact tokamaks. Ignited Spherical Tokamaks (IST),
Zakharo, L. E., White, R. B., Pereverzev, G. V., Gorelenkov, N. N., Krasheninnikov, S. I.   +4 more
core   +1 more source

Measurements of Prompt and MHD-Induced Fast Ion Loss from National Spherical Torus Experiment Plasmas [PDF]

, 2002
A range of effects may make fast ion confinement in spherical tokamaks worse than in conventional aspect ratio tokamaks. Data from neutron detectors, a neutral particle analyzer, and a fast ion loss diagnostic on the National Spherical Torus Experiment ...
Isobe, M., Egedal, J., Kaye, S., Cecil, F. E., Miah, M., Redi, M. H., Wyatt, D., Heidbrink, W. W., Medley, S. S., Yavorskij, V. A., Roquemore, A. L., Paoletti, F., Reznik, S. N., Rosenberg, A., White, R., Darrow, D. S., Alekseyev, A., Gorelenkov, N. N., Goloborod'ko, V. Ya.   +18 more
core   +1 more source

L-H transition studies on MAST: power threshold and heat flux analysis

Nuclear Fusion, 2023
Spherical tokamaks are known to differ from conventional tokamaks in a number of physics areas, but our understanding is limited by a comparative lack of experimental data.
Lena Howlett, István Cziegler, Simon Freethy, Hendrik Meyer, the MAST team   +4 more
doaj   +1 more source

Spherical tokamak development in Brazil [PDF]

Brazilian Journal of Physics, 2003
This paper describes the general characteristics of spherical tokamaks, or spherical tori, with a brief overview of work in this area already performed or in progress at several institutions worldwide. The paper presents also the steps in the development of the ETE (Experimento Tokamak Esferico) project, its research program, technical characteristics ...
Ludwig, G.O., Del Bosco, E., Ferreira, J.G., Berni, L.A., Oliveira, R.M., Andrade, M.C.R., Shibata, C.S., Ueda, M., Barbosa, L.F.W., Barroso, J.J., Castro, P.J., Patire Jr, H.   +11 more
openaire   +3 more sources