A5030710723- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Plasma Diagnostics and Applications
- Fusion materials and technologies
- Ionosphere and magnetosphere dynamics
- Gyrotron and Vacuum Electronics Research
- Antenna Design and Analysis
- Electromagnetic Scattering and Analysis
- Nuclear reactor physics and engineering
- Electromagnetic Launch and Propulsion Technology
- Electromagnetic Simulation and Numerical Methods
- Laser-Plasma Interactions and Diagnostics
- Fault Detection and Control Systems
- High-Energy Particle Collisions Research
- Particle Accelerators and Free-Electron Lasers
- Pulsed Power Technology Applications
- Nuclear Materials and Properties
- Fluid Dynamics Simulations and Interactions
- Radio Frequency Integrated Circuit Design
- Laser-induced spectroscopy and plasma
- Radio Astronomy Observations and Technology
- Lightning and Electromagnetic Phenomena
- Advanced materials and composites
- Underwater Vehicles and Communication Systems
ITER
2019-2024
CEA Cadarache
2014-2021
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2014-2021
Royal Military Academy
2020
Institut de Recherche sur la Fusion par Confinement Magnétique
2015-2017
CEA Grenoble
2017
Abstract For successfully heating plasma with waves in the Ion Cyclotron Range of Frequencies (ICRF), mitigating impurity production is just as crucial maximizing power coupling, especially high-Z environments [Urbanczyk 2021]. Only when coupled limited influence on production, can ICRF truly become a powerful tool to directly deposit energy ions, modify turbulence-driven transport and enhance efficiency fusion reactions. 
To do so, one must rely toroidal array at least three active...
In this paper we validate the finite element code RAPLICASOL, which models radiofrequency wave propagation in edge plasmas near ICRF antennas, against calculations with TOPICA code. We compare output of both codes for ASDEX Upgrade 2-strap antenna, and a 4-strap WEST-like antenna. Although RAPLICASOL requires considerably fewer computational resources than TOPICA, find that predicted quantities experimental interest (including reflection coefficients, coupling resistances, - -matrix entries,...
Abstract As part of ITPA-Integrated Operational Scenario activities, this contribution reviews recent experimental characterizations radio-frequency (RF)-induced scrape-off layer (SOL) modifications various tokamaks worldwide and the LArge Plasma Device at UCLA. The phenomenology, as observed using a large variety measurement techniques, is consistent with expectations from RF sheath rectification. Emphasis then put on complex three-dimensional (3D) spatial patterns RF–SOL interaction, in...
Three identical new WEST Ion Cyclotron Resonance Heating (ICRH) antennas have been designed, assembled then commissioned on plasma from 2013 to 2019.The ICRH system is both load-resilient and compatible with long-pulse operations.The three successfully operated together in 2019 2020.The load resilience capability has demonstrated the antenna feedback controls for phase matching developed.The breakdown detection systems validated protected antennas.The use of combination Lower Hybrid...
We investigate theoretically how sheath radio-frequency (RF) oscillations relate to the spatial structure of near RF parallel electric field E∥ emitted by ion cyclotron (IC) wave launchers. use a simple model slow (SW) evanescence coupled with direct current (DC) plasma biasing via boundary conditions in 3D parallelepiped filled homogeneous cold magnetized plasma. Within 'wide-sheath' asymptotic regime, valid for large-amplitude fields, part this + DC becomes linear: oscillating voltage VRF...
Abstract Radiofrequency sheath rectification is a phenomenon relevant to the operation of Ion Cyclotron Range Frequencies (ICRFs) actuators in tokamaks. Techniques model on 3D ICRF antenna geometries have only recently become available (Shiraiw et al 2023 Nucl. Fusion 63 026024; Beers 2021 Phys. Plasmas 28 093503). In this work, we apply ‘sheath-equivalent dielectric layer’ technique, used previously linear devices (Beers 103508), tokamak geometry, computing rectified potentials WEST...
The design of the WEST (Tungsten-W Environment in Steady-state Tokamak) Ion cyclotron resonance heating antennas is based on a previously tested conjugate-T Resonant Double Loops prototype equipped with internal vacuum matching capacitors. and construction three new ICRH are being carried out close collaboration ASIPP, within framework Associated Laboratory fusion field between IRFM ASIPP. coupling performance to plasma load-tolerance have been improved, while adding Continuous Wave...
In view of improving ion cyclotron range frequencies (ICRF) wave coupling in EAST (experimental advanced superconducting tokamak) necessary to obtain high-power discharges, two series experiments L-mode were devoted the use local gas injection as a tool increase density front antennas. During first session, quantity deuterium simultaneously puffed from five different poloidal positions on each side one ICRF antenna was gradually increased. Steady puffing this (~8.1020 e s−1) increased...
Abstract Midplane gas puffing close to the ion cyclotron range of frequencies (ICRF) antennae has been demonstrated be robust in improving ICRF power coupling current tokamaks. It is also shown a previous study (Zhang 2019 Nucl. Mater. Energy 19 364–71) that ITER, midplane with puff rate ∼4.5 × 10 22 electrons s −1 can increase antenna loading/coupling resistance by about factor two. In this paper, comprehensive parametric carried out characterize influence on additional and broader...
In order to model the sheath rectification in a realistic geometry over size of ion cyclotron resonant heating (ICRH) antennas, self-consistent sheaths and waves for ICH (SSWICH) code couples self-consistently RF wave propagation DC SOL biasing via nonlinear boundary conditions applied at plasma/wall interfaces.A first version SSWICH had 2D (toroidal radial) geometry, rectangular walls either normal or parallel confinement magnetic field B 0 only included evanescent slow (SW) excited...
A European project was undertaken to improve the available SOL ICRF physics simulation tools and confront them with measurements. This paper first reviews code upgrades within project. Using multi-physics finite element solver COMSOL, SSWICH couples RF full-wave propagation DC plasma biasing over "antenna-scale" 2D (toroidal/radial) domains, via non-linear sheath boundary conditions (SBCs) applied at shaped plasma-facing boundaries. For different modules associated SBCs, more elaborate basic...
Plasma heating in the full tungsten (W) environment a steady-state tokamak (WEST) relies on electromagnetic waves both lower hybrid (LH) and ion cyclotron range of frequencies (ICRF). The present study focuses mostly optimization discharges heated with ICRF, by reporting different methods to first optimize wave coupling, their absorption reduce impurity production. It is shown that ICRF coupling can be optimized moving plasma closer antennas, increasing density, frequency LH power. We show...
The JET ICRF ITER-like Antenna (ILA) has been operated at 33, 42 and 47 MHz in 2008–2009 but stopped operation 2009 due to the failure of one tuning capacitors inside antenna. Tests on a spare capacitor showed that micro-leak was caused by cycle wear capacitor's internal bellows. ILA reinstated with new operating scheme minimizing full stroke requests capacitor. This contribution gives an overview works undertaken reinstate up first results plasma. were replaced high voltage tests performed....
The analyses illustrated in this manuscript have been performed order to provide the required data for amplitude-and-phase calibration of D-dot voltage probes used ITER-like antenna at Joint European Torus tokamak. Their equivalent electrical circuit has extracted and analyzed, it compared one installed simple transmission lines. A radio-frequency technique formulated exact mathematical relations derived. This mixes an elegant fashion from measurements numerical calculations retrieve...
SIDON (SImulator of raDiO-frequency Networks) is an in-house developed Radio-Frequency (RF) network solver that has been implemented to cross-validate the design WEST ICRF launchers and simulate their impedance matching algorithm while considering all mutual couplings asymmetries. In this paper, authors illustrate theory as well results its calculations. The have built time-varying plasma scenarios (a sequence front-faces L-mode H-mode Z-matrices), where at each time step (1 millisecond...