Publications related to Magnetohydrodynamics

Iterative removal of sources to model the turbulent electromotive force

Jennifer Waltraud Schober, Abhijit Bhausaheb Bendre

We describe a novel method to compute the components of dynamo tensors from direct magnetohydrodynamic (MHD) simulations. Our method relies upon an extension and generalization of the standard H & ouml;gbom CLEAN algorithm widely used in radio astronomy to ...

Oxford Univ Press2024

Interpretative 3D MHD modelling of deuterium SPI into a JET H-mode plasma

Cristian Sommariva, Umar Sheikh, Mengdi Kong, Haomin Sun

The pre-thermal quench (pre-TQ) dynamics of a pure deuterium ( D 2 ) shattered pellet injection (SPI) into a 3 MA / 7 MJ JET H-mode plasma is studied via 3D non-linear MHD modelling with the JOREK code. The interpretative modelling captures the overall evo ...

IOP Publishing Ltd2024

Shedding light on the MRI-driven dynamo in a stratified shearing box

Abhijit Bhausaheb Bendre

We study the magneto-rotational instability (MRI) dynamo in a geometrically thin disc (H/R < 1) using stratified zero net (vertical) flux shearing box simulations. We find that mean fields and electromotive forces (EMFs) oscillate with a primary frequency ...

2024

Scenario optimization for the tokamak ramp-down phase in RAPTOR. Part B: safe termination of DEMO plasmas

Olivier Sauter, Federico Alberto Alfredo Felici, Simon Van Mulders, Cassandre Ekta Contré, Emiliano Fable, Anna Teplukhina

An optimized plasma current ramp-down strategy is critical for safe and fast termination of plasma discharges in a tokamak demonstration fusion reactor (DEMO), both in planned and emergency scenarios, avoiding plasma disruptions and excessive heat loads to ...

Iop Publishing Ltd2024

Global fluid simulation of plasma turbulence in stellarators with the GBS code

Paolo Ricci, Joaquim Loizu Cisquella, António João Caeiro Heitor Coelho

The implementation of three-dimensional magnetic fields, such as the ones of stellarators, in the GBS code (Ricci et al 2012 Plasma Phys. Control. Fusion54 124047; Giacomin et al 2022 J. Comput. Phys.464 111294) is presented, and simulation results are dis ...

IOP Publishing Ltd2024

Benign termination of runaway electron beams on ASDEX Upgrade and TCV

Basil Duval, Stefano Coda, Joan Decker, Umar Sheikh, Luke Simons, Claudia Colandrea, Jean Arthur Cazabonne, Bernhard Sieglin, Gergely Papp

This paper discusses the development of a benign termination scenario for runaway electron (RE) beams on ASDEX Upgrade and TCV. A systematic study revealed that a low electron density (n e) companion plasma was required to achieve a large MHD instability, ...

Iop Publishing Ltd2024

Progress in the development of the ITER baseline scenario in TCV

Olivier Sauter, Stefano Coda, Benoît Labit, Alessandro Pau, Alexander Karpushov, Antoine Pierre Emmanuel Alexis Merle, Oleg Krutkin, Cassandre Ekta Contré, Reinart Andreas J. Coosemans, Yann Camenen, Olivier Claude Martin Février, Matteo Vallar, Filippo Bagnato, Simon Van Mulders, Stefano Marchioni

Under the auspices of EUROfusion, the ITER baseline (IBL) scenario has been jointly investigated on AUG and TCV in the past years and this paper reports on the developments on TCV. It is found that the performance of TCV IBL is mainly limited by (neoclassi ...

2024

Sensitivity Analysis of the Lumped Thermal Model of the EU 170 GHz Gyrotron Magnetron Injection Gun

Jean-Philippe Hogge, Francisco Sanchez

The ITER Electron Cyclotron Resonance Heating and Current Drive (ECRH&CD) system relies on 1 MW 170 GHz Gyrotrons to provide the mm-wave power needed for plasma heating, current drive, and magneto-hydrodynamic control. The design and modeling of the contro ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Modelling of energetic particle drive and damping effects on TAEs in AUG experiment with ECCD

Alexander Karpushov, Giovanni Tardini

The impact of electron cyclotron current drive (ECCD)-driven current on toroidicity-induced Alfven eigenmodes (TAEs) in experiments on the AUG tokamak is investigated numerically. The dynamical evolution of the plasma profiles and equilibria are modelled w ...

IOP Publishing Ltd2024

Global fluid simulations of plasma turbulence in stellarators

António João Caeiro Heitor Coelho

In order to cope with the decarbonization challenge faced by many countries, fusion is one of the few alternatives to fossil fuels for the production of electricity. Two devices invented in the middle of the previous century have emerged as the most promis ...

EPFL2024

Waterborne Virus Transport and Risk Assessment in Lake Geneva Under Climate Change

Tamar Kohn, Chaojie Li

Climate changes influence lake hydrodynamics and radiation levels and thus may affect the fate and transport of waterborne pathogens in lakes. This study examines the impact of climate change on the fate, transport, and associated risks of four waterborne ...

2024

Occam's razor on the mechanism of resistive-wall-mode-induced beta limits in diverted tokamaks

Jonathan Graves, Daniele Brunetti

External kink modes, believed to be the drive of the 0-limiting resistive wall mode, are strongly stabilized by the presence of a separatrix. We thus propose a novel mechanism explaining the appearance of long-wavelength global instabilities in free bounda ...

2023

Nonlinear saturation of resistive tearing modes in a cylindrical tokamak with and without solving the dynamics

Joaquim Loizu Cisquella

We show that the saturation of resistive tearing modes in a cylindrical tokamak, as well as the corresponding island width, can be directly calculated with a magnetohydrodynamics (MHD) equilibrium code without solving the dynamics and without considering r ...

Cambridge University Press2023

Numerical tools for burning plasmas

Jonathan Graves, Laurent Villard, Emmanuel Lanti, Baruch Rofman, Alberto Bottino, Ben McMillan, Xiao Wang, Emanuele Poli

The software stack under development within a European coordinated effort on tools for burning plasma modelling is presented. The project is organised as a Task (TSVV Task 10) under the new E-TASC initiative (Litaudon et al 2022 Plasma Phys. Control. Fusio ...

IOP Publishing Ltd2023

Nonlinear interaction of Alfvénic instabilities and turbulence via the modification of the equilibrium profiles

Laurent Villard, Alberto Bottino, Xiao Wang

Nonlinear simulations of Alfvén modes (AMs) driven by energetic particles (EPs) in the presence of turbulence are performed with the gyrokinetic particle-in-cell code ORB5. The AMs carry a heat flux, and consequently they nonlinearly modify the plasma temp ...

Cambridge University Press2023

Study of correlations between LOC/SOC transition, intrinsic toroidal rotation reversal and TEM/ITG bifurcation with different working gases in TCV

Basil Duval, Oleg Krutkin, Filippo Bagnato, Aylwin Iantchenko

The effects of different working gases on the transition from linear ohmic confinement (LOC) regime to saturated ohmic confinement (SOC) regime and its relation to the intrinsic toroidal rotation reversal phenomenon were explored in the TCV tokamak. The en ...

IOP Publishing Ltd2023

Predictive modeling of Alfvén eigenmode stability in inductive scenarios in JT-60SA

Javier García Hernández, Matteo Vallar, Antonio José Pereira de Figueiredo

The JT-60SA device offers unique conditions before ITER for the study of the interaction of energetic particles with plasma waves. With similar dimensions to JET, e.g., a major radius but with a slightly more elongated plasma volume, JT-60SA is used as a h ...

Frontiers Media Sa2023

Locked mode detection during error field identification studies

Olivier Sauter

At the beginning of a machine operation, an assessment of the intrinsic error fields, spurious magnetic field perturbations which can affect plasma dynamics, is often carried out by executing the compass scan method [Scoville J.T. et al. Nucl. Fusion 43 25 ...

ELSEVIER SCIENCE SA2023

Excitation of toroidal Alfvén eigenmodes with counter-current NBI in the TCV tokamak

Laurie Porte, Matteo Vallar, Alexander Karpushov, Samuele Mazzi

In TCV, unstable modes excited by resonant interaction between the shear Alfvèn waves in con- tinuum gaps and energetic particles have been observed in scenarios with Neutral Beam Injection (NBI). TCV is a middle-size device (R 0 /a = 0.88/0.25) equipped w ...

IOP Publishing Ltd2023

Exploration of the parameter space for the excitation and saturation of Edge Harmonic Oscillations

Guillermo Bustos Ramirez

This thesis presents advancements in the understanding of the plasma conditions leading to the excitation and saturation of the Edge Harmonic Oscillations (EHOs) observed during QH-mode operation in tokamak plasmas. Such operations represent a safer altern ...

EPFL2023