Results 71 to 80 of about 1,247 (174)

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

Gyrokinetic particle simulation model [PDF]

Journal of Computational Physics, 1987
A new type of particle simulation model based on the gyrophase-averaged Vlasov and Poisson equations is presented. The reduced system in which particle gyrations are removed from the equations of motion while the finite Larmor radius effects are still preserved, is most suitable for studying low frequency microinstabilities in magnetized plasmas.
openaire   +3 more sources

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

Alfven Wave Collisions, The Fundamental Building Block of Plasma Turbulence II: Numerical Solution

, 2013
This paper presents the numerical verification of an asymptotic analytical solution for the nonlinear interaction between counterpropagating Alfven waves, the fundamental building block of astrophysical plasma turbulence. The analytical solution, derived
Dorland, William, Howes, Gregory G., Nielson, Kevin D.   +2 more
core   +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

Analytic slowing-down distributions as modified by turbulent transport

, 2018
The effect of electrostatic microturbulence on fast particles rapidly decreases at high energy, but can be significant at moderate energy. Previous studies found that, in addition to changes in the energetic particle density, this results in nontrivial ...
Wilkie, George J.
core   +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

Understanding nonlinear saturation in zonal-flow-dominated ion temperature gradient turbulence

, 2015
We propose a quantitative model of ion temperature gradient driven turbulence in toroidal magnetized plasmas. In this model, the turbulence is regulated by zonal flows, i.e. mode saturation occurs by a zonal-flow-mediated energy cascade ("shearing"), and
Jenko, F., Navarro, A. Bañón, Plunk, G. G.   +2 more
core   +1 more source

Gyrokinetic field theory

Physics of Plasmas, 2000
The Lagrangian formulation of the gyrokinetic theory is generalized in order to describe the particles’ dynamics, as well as the self-consistent behavior of the electromagnetic fields. The gyrokinetic equation for the particle distribution function and the gyrokinetic Maxwell’s equations, for the electromagnetic fields, are both derived from the ...
openaire   +1 more source

First global gyrokinetic profile predictions of ITER burning plasma

Nuclear Fusion
In this work, we present the first global gyrokinetic simulations of the ITER baseline scenario at 15 MA, performed using the GENE-Tango framework in both electrostatic and electromagnetic regimes.
A. Di Siena, C. Bourdelle, A. Bañón Navarro, G. Merlo, T. Görler, E. Fransson, A. Polevoi, S.H. Kim, F. Koechl, A. Loarte, E. Fable, C. Angioni, P. Mantica, F. Jenko   +13 more
doaj   +1 more source