Results 81 to 90 of about 158 (153)

The impact of E × B shear on microtearing based transport in spherical tokamaks

Nuclear Fusion
Electromagnetic microtearing modes (MTMs) have been observed in many different spherical tokamak (ST) regimes. Understanding how these and other electromagnetic modes nonlinearly saturate is likely critical in understanding the confinement of a high β ST.
B.S. Patel, M.R. Hardman, D. Kennedy, M. Giacomin, D. Dickinson, C.M. Roach   +5 more
doaj   +1 more source

Prediction of performance and turbulence in ITER burning plasmas via nonlinear gyrokinetic profile prediction

Nuclear Fusion
Burning plasma performance, transport, and the effect of hydrogen isotope (H, D, D-T fuel mix) on confinement has been predicted for ITER baseline scenario (IBS) conditions using nonlinear gyrokinetic profile predictions.
N.T. Howard, P. Rodriguez-Fernandez, C. Holland, J. Candy   +3 more
doaj   +1 more source

A general framework for quantifying uncertainty at scale. [PDF]

Commun Eng, 2022
Farcaş IG, Merlo G, Jenko F.
europepmc   +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

Transport Barriers in magnetized plasmas- general theory with dynamical constraints

Nuclear Fusion
A fundamental dynamical constraint—that fluctuation induced charge-weighted particle flux must vanish- can prevent instabilities from accessing the free energy in the strong gradients characteristic of Transport Barriers (TBs).
M. Kotschenreuther, X. Liu, S.M. Mahajan, D.R. Hatch, G. Merlo   +4 more
doaj   +1 more source

Multiscale gyrokinetics for rotating tokamak plasmas: II. Reduced models for electron dynamics

New Journal of Physics, 2013
In this paper, we extend the multiscale approach developed in Abel et al (2012 Rep. Prog. Phys. submitted) by exploiting the scale separation between ions and the electrons. The gyrokinetic equation is expanded in powers of the electron to ion mass ratio,
I G Abel, S C Cowley
doaj   +1 more source

On the importance of parallel magnetic-field fluctuations for electromagnetic instabilities in STEP

Nuclear Fusion
This paper discusses the importance of parallel perturbations of the magnetic-field in gyrokinetic simulations of electromagnetic instabilities and turbulence at mid-radius in the burning plasma phase of the conceptual high- β , reactor-scale, tight ...
D. Kennedy, C.M. Roach, M. Giacomin, P.G. Ivanov, T. Adkins, F. Sheffield, T. Görler, A. Bokshi, D. Dickinson, H.G. Dudding, B.S. Patel   +10 more
doaj   +1 more source

Considering fluctuation energy as a measure of gyrokinetic turbulence

New Journal of Physics, 2012
In gyrokinetic theory, there are two quadratic measures of fluctuation energy, left invariant under nonlinear interactions, that constrain turbulence. In a recent work (Plunk and Tatsuno 2011 Phys. Rev. Lett.
G G Plunk, T Tatsuno, W Dorland
doaj   +1 more source

Kinetic plasma-wall interaction using immersed boundary conditions

Nuclear Fusion
The interaction between a plasma and a solid surface is studied in a (1D-1V) kinetic approach using immersed boundary conditions and penalization to model the wall.
Yann Munschy, Emily Bourne, Guilhem Dif-Pradalier, Peter Donnel, Philippe Ghendrih, Virginie Grandgirard, Yanick Sarazin   +6 more
doaj   +1 more source

Overview of multiscale turbulence studies covering ion-to-electron scales in magnetically confined fusion plasma

Nuclear Fusion
Turbulent transport in magnetically confined fusion plasma has conventionally been analyzed at the ion gyroradius scale based on the microturbulence theory.
S. Maeyama, N.T. Howard, J. Citrin, T.-H. Watanabe, T. Tokuzawa   +4 more
doaj   +1 more source