Federico David Halpern

Cette personne n’est plus à l’EPFL

À propos
Confidentialité
Mentions légales

Graph Chatbot

Publications associées (31)

Turbulent regimes in the tokamak scrape-off layer

Sébastien Jolliet, Joaquim Loizu Cisquella, Paolo Ricci, Annamaria Mosetto, Federico David Halpern

We identify the turbulent regimes in the tokamak scrape-off layer as a function of plasma resistivity, electron to ion mass ratio, safety factor, and magnetic shear. We find that two main instabilities drive turbulence in the SOL: Drift Waves, with their r ...

2013

Ideal ballooning modes in the tokamak scrape-off layer

Sébastien Jolliet, Joaquim Loizu Cisquella, Paolo Ricci, Annamaria Mosetto, Federico David Halpern

A drift-reduced Braginskii fluid model is used to carry out a linear and non-linear study of ideal ballooning modes in the tokamak scrape-off layer. First, it is shown that the scrape-off layer finite connection length and boundary conditions modify the id ...

American Institute of Physics2013

Magnetohydrodynamic helical structures in nominally axisymmetric low-shear tokamak plasmas

Wilfred Anthony Cooper, Antoine Pochelon, Olivier Sauter, Holger Reimerdes, Jonathan Graves, Federico David Halpern, Daniele Brunetti

The primary goal of hybrid scenarios in tokamaks is to enable high performance operation with large plasma currents whilst avoiding MHD instabilities. However, if a local minimum in the safety factor is allowed to approach unity, the energy required to ove ...

Iop Publishing Ltd2013

Bifurcated Helical Core Equilibrium States in Tokamaks

Wilfred Anthony Cooper, Basil Duval, Antoine Pochelon, Olivier Sauter, Trach-Minh Tran, Holger Reimerdes, Stefano Coda, Jonathan Graves, Benoît Labit, David Pfefferlé, Federico David Halpern, Daniele Brunetti

Tokamaks with weak to moderate reversed central shear in which the minimum inverse rotational transform (safety factor) qmin is in the neighbourhood of unity can trigger bifurcated magnetohydrodynamic equilibrium states, one of which is similar to a satura ...

IOP Publishing Ltd2013

Turbulent regimes in the tokamak scrape-off layer

Sébastien Jolliet, Joaquim Loizu Cisquella, Paolo Ricci, Annamaria Mosetto, Federico David Halpern

The non-linear turbulent regimes in the tokamak scrape-off layer (SOL) are identified according to the linear instability responsible for the perpendicular transport. Four regions of the SOL operational parameters are determined where turbulence is driven ...

American Institute of Physics2013

Theory-based scaling of the SOL width in circular limited tokamak plasmas

Gilles Arnoux, Ivo Furno, Sébastien Jolliet, Jan Horacek, Benoît Labit, Joaquim Loizu Cisquella, Paolo Ricci, Annamaria Mosetto, Federico David Halpern

A theory-based scaling for the characteristic length of a circular, limited tokamak scrape-off layer (SOL) is obtained by considering the balance between parallel losses and non-linearly saturated resistive ballooning mode turbulence driving anomalous perp ...

IOP Publishing Ltd2013

Boundary conditions for plasma fluid models at the magnetic presheath entrance

Sébastien Jolliet, Joaquim Loizu Cisquella, Paolo Ricci, Federico David Halpern

The proper boundary conditions at the magnetic presheath entrance for plasma fluid turbulence models based on the drift approximation are derived, focusing on a weakly collisional plasma sheath with Ti≪Te and a magnetic field oblique to a totally absorbing ...

American Institute of Physics2012

Bifurcated Helical Core Equilibrium States in Tokamaks

Wilfred Anthony Cooper, Basil Duval, Antoine Pochelon, Olivier Sauter, Holger Reimerdes, Stefano Coda, Jonathan Rossel, Jonathan Graves, Benoît Labit, David Pfefferlé, Mattia Albergante, Federico David Halpern, Daniele Brunetti

Tokamaks with weak to moderate reversed central shear in which the minimum rotational transform

q_{min}

is in the neighbourhood of unity can trigger bifurcated MagnetoHydrodynamic (MHD) equilibrium states, one of which is similar to a saturated ideal ...

2012

Simulation of plasma turbulence in scrape-off layer conditions: the GBS code, simulation results and code validation

Ambrogio Fasoli, Ivo Furno, Sébastien Jolliet, Joaquim Loizu Cisquella, Paolo Ricci, Christian Gabriel Theiler, Annamaria Mosetto, Federico David Halpern

Based on the drift-reduced Braginskii equations, the Global Braginskii Solver, GBS, is able to model the scrape-off layer (SOL) plasma turbulence in terms of the interplay between the plasma outflow from the tokamak core, the turbulent transport, and the l ...

Iop Publishing Ltd2012

Diamagnetic thresholds for sawtooth cycling in tokamak plasmas

Federico David Halpern

The cycling dynamics of the internal kink mode, which drives sawtooth oscillations in tokamak plasmas, is studied using the three dimensional, non-linear magnetohydrodynamic (MHD) code XTOR-2F [H. Lütjens and J.-F. Luciani, J. Comput. Phys. 229, 8130 (2010 ...

American Institute of Physics2011

Simulation of electron thermal transport in H-mode discharges

Federico David Halpern

American Institute of Physics2009

Page 2 sur 2