Results 51 to 60 of about 158 (153)

Coarse-grained gyrokinetics for the critical ion temperature gradient in stellarators

Physical Review Research, 2022
We present a modified gyrokinetic theory to predict the critical gradient that determines the linear onset of the ion temperature gradient (ITG) mode in stellarator plasmas.
G. T. Roberg-Clark, G. G. Plunk, P. Xanthopoulos   +2 more
doaj   +1 more source

Kinetic Theory of Drift‐Mirror Mode

Geophysical Research Letters, Volume 51, Issue 18, 28 September 2024.
Abstract We present a nonlocal gyrokinetic theory for the drift‐mirror mode in high‐β $\beta $ anisotropic plasmas. Here, β $\beta $ represents the ratio of plasma pressure to magnetic pressure. The equilibrium distribution is established self‐consistently via guiding‐center Hamiltonian theory.
Yao Yao, Haotian Chen, Zilong Li, Jiquan Li   +3 more
wiley   +1 more source

Modeling electron temperature profiles in the pedestal with simple formulas for ETG transport

Nuclear Fusion
This paper reports on the refinement (building on (Hatch D.R. et al 2022 Phys. Plasmas 29 062501)) and application of simple formulas for electron heat transport from electron temperature gradient (ETG) driven turbulence in the pedestal. The formulas are
D.R. Hatch, M.T. Kotschenreuther, P.-Y. Li, B. Chapman-Oplopoiou, J. Parisi, S.M. Mahajan, R. Groebner   +6 more
doaj   +1 more source

Scalable Quasineutral Solver for Gyrokinetic Simulation [PDF]

, 2012
La modélisation du transport turbulent est un point clef pour prédire les propriétés de confinement d'un plasma de fusion. La théorie gyrocinétique propose une description à 5 dimensions permettant de calculer et comprendre les effets cinétiques dans un plasma.
Latu, Guillaume, Grandgirard, Virginie, Crouseilles, Nicolas, Dif-Pradalier, Guilhem   +3 more
openaire   +2 more sources

A numerical instability in an ADI algorithm for gyrokinetics [PDF]

Computer Physics Communications, 2005
We explore the implementation of an Alternating Direction Implicit (ADI) algorithm for a gyrokinetic plasma problem and its resulting numerical stability properties. This algorithm, which uses a standard ADI scheme to divide the field solve from the particle distribution function advance, has previously been found to work well for certain plasma ...
Emily Ann Belli, Gregory W. Hammett
openaire   +1 more source

Direct Evidence of Drift‐Compressional Wave Generation in the Earth's Magnetosphere Detected by Arase

Geophysical Research Letters, Volume 51, Issue 8, 28 April 2024.
Abstract We present the first direct evidence of an in situ excitation of drift‐compressional waves driven by drift resonance with ring current protons in the magnetosphere. Compressional Pc4–5 waves with frequencies of 4–12 mHz were observed by the Arase satellite near the magnetic equator at L ∼ 6 in the evening sector on 19 November 2018.
K. Yamamoto, A. V. Rubtsov, D. V. Kostarev, P. N. Mager, D. Yu. Klimushkin, M. Nosé, A. Matsuoka, K. Asamura, Y. Miyoshi, S. Yokota, S. Kasahara, T. Hori, K. Keika, Y. Kasahara, A. Kumamoto, F. Tsuchiya, M. Shoji, S. Nakamura, I. Shinohara   +18 more
wiley   +1 more source

Stability and transport of gyrokinetic critical pedestals

Nuclear Fusion
A gyrokinetic threshold model for pedestal width–height scaling prediction is applied to multiple devices. A shaping and aspect ratio scan is performed on National Spherical Torus Experiment (NSTX) equilibria, finding $\Delta_{\mathrm{ped}} = 0.92 A^{1 ...
J.F. Parisi, A.O. Nelson, W. Guttenfelder, R. Gaur, J.W. Berkery, S.M. Kaye, K. Barada, C. Clauser, A. Diallo, D.R. Hatch, A. Kleiner, M. Lampert, T. Macwan, J.E. Menard   +13 more
doaj   +1 more source

Integrated modelling of neon impact on JET H-mode core plasmas

Nuclear Fusion, 2022
Nuclear fusion reactor plasmas will need to exhaust a significant proportion of energy flux through radiative processes, to enable acceptable divertor loads. This can be obtained by line radiation from impurities, injected from the plasma edge. There are
M. Marin, J. Citrin, C. Giroud, C. Bourdelle, Y. Camenen, L. Garzotti, A. Ho, M. Sertoli, JET Contributors   +8 more
doaj   +1 more source

Numerical study of limits of neoclassical theory in the plateau regime in the presence of impurities

Contributions to Plasma Physics, Volume 64, Issue 3, March 2024.
Abstract This paper presents a numerical simulation to test the corrections to the radial electric field in the presence of impurities for tokamak devices whose main ions are in the plateau regime. The effects due to the presence of impurity density variation in a pedestal tokamak are known to generate conditions where conventional neoclassical theory ...
Riccardo Nicolò Iorio, T. P. Kiviniemi, E. Hirvijoki, L. Chône, S. Janhunen, F. Albert, S. Leerink   +6 more
wiley   +1 more source

Reduced electrostatic turbulence in the quasi-isodynamic stellarator configuration CIEMAT-QI4

Nuclear Fusion
CIEMAT-QI4 is a quasi-isodynamic stellarator configuration that simultaneously features very good fast-ion confinement in a broad range of β values, low neoclassical transport and bootstrap current, and ideal magnetohydrodynamic stability up to $\beta ...
J.M. García-Regaña, I. Calvo, E. Sánchez, H. Thienpondt, J.L. Velasco, J.A. Capitán   +5 more
doaj   +1 more source