358 citations · 2.3k across the 35 of their papers we have counts for
22 papers · 1 filter
Towards continuum gyrokinetic study of high-field mirrors
Manaure Francisquez, Maxwell H. Rosen, Noah R. Mandell +3
High-temperature superconducting (HTS) magnetic mirrors under development exploit strong fields with high mirror ratio to compress loss cones and enhance confinement, and may offer…
Global gyrokinetic simulations of ASDEX Upgrade up to the transport time-scale with GENE-Tango
A. Di Siena, A. Banon Navarro, T. Luda +12
An accurate description of turbulence up to the transport time scale is essential for predicting core plasma profiles and enabling reliable calculations for designing advanced scen…
Kinetic modeling of neutral transport for a continuum gyrokinetic code
T. N. Bernard, F. D. Halpern, M. Francisquez +6
We present the first-of-its-kind coupling of a continuum full-f gyrokinetic turbulence model with a 6D continuum model for kinetic neutrals, carried out using the Gkeyll code. Our…
Reduction of transport due to magnetic shear in gyrokinetic simulations of the scrape-off layer
N. R. Mandell, G. W. Hammett, A. Hakim +1
The effect of varying magnetic shear on scrape-off layer turbulence and profiles is studied via electromagnetic gyrokinetic simulations of a helical scrape-off layer model. We deve…
Turbulent broadening of electron heat-flux width in electromagnetic gyrokinetic simulations of a helical scrape-off layer model
N. R. Mandell, G. W. Hammett, A. Hakim +1
We demonstrate that cross-field transport in the scrape-off layer (SOL) can be moderately increased by electromagnetic effects in high-beta regimes, resulting in a broader electron…
Mapped discontinuous Galerkin interpolations and sheared boundary conditions
Manaure Francisquez, Noah R. Mandell, Ammar Hakim +1
Translations or, more generally, coordinate transformations of scalar fields arise in several applications, such as weather, accretion disk and magnetized plasma turbulence modelin…
Improved multispecies Dougherty collisions
Manaure Francisquez, James Juno, Ammar Hakim +2
The Dougherty model Fokker-Planck operator is extended to describe nonlinear full-f collisions between multiple species in plasmas. Simple relations for cross-species interactions…
Investigating shear flow through continuum gyrokinetic simulations of limiter biasing in the Texas Helimak
Tess N. Bernard, Timothy Stoltzfus-Dueck, Kenneth W. Gentle +3
Previous limiter-biasing experiments on the Texas Helimak, a simple magnetized torus, have been inconclusive on the effect of flow shear on turbulence levels. To investigate this,…
Fluid & Gyrokinetic turbulence in open field-line, helical plasmas
Manaure Francisquez, Tess N. Bernard, Ben Zhu +3
Two-fluid Braginskii codes have simulated open-field line turbulence for over a decade, and only recently has it become possible to study these systems with continuum gyrokinetic c…
Electromagnetic full- gyrokinetics in the tokamak edge with discontinuous Galerkin methods
N. R. Mandell, A. Hakim, G. W. Hammett +1
We present an energy-conserving discontinuous Galerkin scheme for the full- electromagnetic gyrokinetic system in the long-wavelength limit. We use the symplectic formulation an…
Gyrokinetic continuum simulations of plasma turbulence in the Texas Helimak
Tess N. Bernard, Eric L. Shi, Kenneth Gentle +4
The first gyrokinetic simulations of plasma turbulence in the Texas Helimak device, a simple magnetized torus, are presented. The device has features similar to the scrape-off laye…
Gyrokinetic continuum simulation of turbulence in a straight open-field-line plasma
E. L. Shi, G. W. Hammett, T. Stoltzfus-Dueck +1
3D2V continuum gyrokinetic simulations of electrostatic plasma turbulence in a straight, open-field-line geometry have been performed using the full- discontinuous-Galerkin code…
Scrape-Off Layer Turbulence in Tokamaks Simulated with a Continuum Gyrokinetic Code
A. Hakim, E. L. Shi, I. G. Abel +2
We are developing a new continuum gyrokinetic code, Gkeyll, for use in edge plasma simulations, and here present initial simulations of turbulence on open field lines with model sh…
Phase mixing vs. nonlinear advection in drift-kinetic plasma turbulence
A. A. Schekochihin, J. T. Parker, E. G. Highcock +3
A scaling theory of long-wavelength electrostatic turbulence in a magnetised, weakly collisional plasma (e.g., ITG turbulence) is proposed, with account taken both of the nonlinear…
A Gyrokinetic 1D Scrape-Off Layer Model of an ELM Heat Pulse
E. L. Shi, A. H. Hakim, G. W. Hammett
An electrostatic gyrokinetic-based model is applied to simulate parallel plasma transport in the scrape-off layer to a divertor plate. The authors focus on a test problem that has…
Intrinsic momentum transport in up-down asymmetric tokamaks
Justin Ball, Felix I. Parra, Michael Barnes +4
Recent work demonstrated that breaking the up-down symmetry of tokamak flux surfaces removes a constraint that limits intrinsic momentum transport, and hence toroidal rotation, to…
An Oscillating Langevin Antenna for Driving Plasma Turbulence Simulations
J. M. TenBarge, G. G. Howes, W. Dorland +1
A unique method of driving Alfvenic turbulence via an oscillating Langevin antenna is presented. This method of driving is motivated by a desire to inject energy into a finite doma…
Gyrokinetic studies of the effect of beta on drift-wave stability in NCSX
J. A. Baumgaertel, G. W. Hammett, D. R. Mikkelsen +2
The gyrokinetic turbulence code GS2 was used to investigate the effects of plasma beta on linear, collisionless ion temperature gradient (ITG) modes and trapped electron modes (TEM…
Comparing linear ion-temperature-gradient-driven mode stability of the National Compact Stellarator Experiment and a shaped tokamak
J. A. Baumgaertel, G. W. Hammett, D. R. Mikkelsen
One metric for comparing confinement properties of different magnetic fusion energy configurations is the linear critical gradient of drift wave modes. The critical gradient scale…
Gyrokinetic statistical absolute equilibrium and turbulence
Jian-Zhou Zhu, Gregory W. Hammett
A paradigm based on the absolute equilibrium of Galerkin-truncated inviscid systems to aid in understanding turbulence [T.-D. Lee, "On some statistical properties of hydrodynamical…
Gyrokinetic turbulence: a nonlinear route to dissipation through phase space
A. A. Schekochihin, S. C. Cowley, W. Dorland +5
This paper describes a conceptual framework for understanding kinetic plasma turbulence as a generalized form of energy cascade in phase space. It is emphasized that conversion of…
Non-existence of normal tokamak equilibria with negative central current
G. W. Hammett, S. C. Jardin, B. C. Stratton
Recent tokamak experiments employing off-axis, non-inductive current drive have found that a large central current hole can be produced. The current density is measured to be appro…