A5052759526- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Fusion materials and technologies
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Generative Adversarial Networks and Image Synthesis
- Laser-Plasma Interactions and Diagnostics
- Fluid Dynamics and Turbulent Flows
- Nuclear reactor physics and engineering
- Plasma Diagnostics and Applications
- Nuclear Physics and Applications
- Solar and Space Plasma Dynamics
- Advanced Image Processing Techniques
- Advanced Sensor and Control Systems
- Physics of Superconductivity and Magnetism
- Viral Infections and Vectors
- Engineering Applied Research
- Advanced Image and Video Retrieval Techniques
- Cytomegalovirus and herpesvirus research
- Silicon and Solar Cell Technologies
- Vacuum and Plasma Arcs
- Meteorological Phenomena and Simulations
- Geomagnetism and Paleomagnetism Studies
- Laser-induced spectroscopy and plasma
- Dust and Plasma Wave Phenomena
École Polytechnique Fédérale de Lausanne
2018-2023
Plasma Technology (United States)
2023
Fusion Academy
2023
Fusion (United States)
2023
National Centre for Nuclear Research
2021
Self-consistent full-size turbulent-transport simulations of the divertor and SOL existing tokamaks have recently become feasible. This enables direct comparison turbulence against experimental measurements. In this work, we perform a series diverted Ohmic L-mode discharges on TCV tokamak, building first-of-a-kind dataset for validation edge models. dataset, referred to as TCV-X21, contains measurements from 5 diagnostic systems -- giving total 45 1- 2-D observables in two toroidal magnetic...
A new Gas Puff Imaging (GPI) diagnostic has been installed on the TCV tokamak, providing two-dimensional insights into Scrape-Off-Layer (SOL) turbulence dynamics above, at and below magnetic X-point. detailed study in L-mode, attached, lower single-null discharges shows that statistical properties have little poloidal variations, while vast differences are present 2D behaviour of intermittent filaments. Strongly elongated filaments, just above X-point divertor far-SOL, show a good...
Abstract Using recently installed scrape-off layer diagnostics on the tokamak à configuration variable, we characterise poloidal and parallel properties of turbulent filaments. We access both attached detached divertor conditions across a wide range core densities ( f G ∈ [0.09, 0.66]) in diverted L-mode plasma configurations. With gas puff imaging (GPI) diagnostic at outer midplane observed filaments with monotonic increase radial velocity (from 390 m s −1 to 800 ) cross-field radii 8.5 mm...
Abstract Multi-spectral imaging of helium atomic emission (HeMSI) has been used to create 2D poloidal maps <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>T</mml:mi> </mml:mrow> <mml:mi mathvariant="normal">e</mml:mi> </mml:msub> </mml:math> and <mml:mi>n</mml:mi> in TCV’s divertor. To achieve these measurements, MANTIS multispectral cameras (Perek et al 2019 Rev. Sci. Instrum. 90 123514) simultaneously imaged four He I lines (two...
The analysis of turbulence in plasmas is fundamental fusion research. Despite extensive progress theoretical modeling the past 15 years, we still lack a complete and consistent understanding magnetic confinement devices, such as tokamaks. Experimental studies are challenging due to diverse processes that drive high-speed dynamics turbulent phenomena. This work presents novel application motion tracking identify track filaments plasmas, called blobs, high-frequency video obtained from Gas...
Transport processes around the magnetic X-point of tokamaks, such as turbulence and mean-field drifts, are scarcely understood. The assessment capability codes to quantitatively reproduce these dynamics has been hampered by limitations in computational power available experimental data. In this paper, we present a rigorous validation full-scale simulations newly developed scenario basic toroidal plasma device TORPEX, performed with four state-of-the-art FELTOR, GBS, GRILLIX, STORM....
Abstract Magnetically confined fusion plasmas with negative triangularity ( δ ) exhibit greater L-mode confinement than positive . Recent experiments in the TCV and DIII-D tokamaks have correlated improvement to a reduction of fluctuations within plasma core. We report on fluctuation measurements scrape-off layer (SOL) for −0.61 < +0.64 limited diverted ohmic plasmas; these reveal strong SOL amplitudes at ≲ −0.25, and, surprisingly, an almost full suppression interaction main-chamber...
Abstract Cross-field transport of particles in the boundary region magnetically confined fusion plasmas is dominated by turbulence. Blobs, intermittent turbulent structures with large amplitude and a filamentary shape appearing scrape-off layer (SOL), are known from theoretical experimental studies to be main contributor cross-field particle transport. The dynamics blobs differs depending on various plasma conditions, including triangularity ( δ ). In this work, we analyze dependence at...
A variable configuration V-band heterodyne Doppler back-scattering diagnostic has been recently made operational in the tokamak à variable. This article describes hardware setup options, flexible quasi-optical launcher antenna, data-analysis techniques, and first data. The uses a fast arbitrary waveform generator as main oscillator commercial vector network analyzer extension modules mm-wave hardware. It allows sweepable single or multi-frequency operation. antenna 3D poloidal (10°-58°)...
We present the design and operation of a suite Gas Puff Imaging (GPI) diagnostic systems installed on Tokamak à Configuration Variable (TCV) for study turbulence in plasma edge Scrape-Off-Layer (SOL). These provide unique ability to simultaneously collect poloidal 2D images dynamics at outboard midplane, around X-point, both High-Field Side (HFS) Low-Field (LFS) SOL, divertor region. describe characterize an innovative control system deuterium helium gas injection, which is becoming default...
Filamentary structures, also known as blobs, are a prominent feature of turbulence and transport at the edge magnetically confined plasmas. They cause cross-field particle energy are, therefore, interest in tokamak physics and, more generally, nuclear fusion research. Several experimental techniques have been developed to study their properties. Among these, measurements routinely performed with stationary probes, passive imaging, recent years, Gas Puff Imaging (GPI). In this work, we...
Abstract To reliably predict the distribution of heat and particle fluxes at target plates tokamaks, a comprehensive understanding turbulence throughout entire Scrape-Off-Layer (SOL) is imperative. This study examines divertor systematically across broad parameter range on TCV tokamak, including variations in magnetic field direction, plasma current <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mi>I</mml:mi> <mml:mi...
Abstract The I-phase is an H-mode confinement regime of tokamaks characterized by limit cycle oscillations, the so-called LCOs or bursts. These bursts are manifestation a periodic flattening plasma edge pressure profile. profile caused increased radial transport, driven high-frequency mode that periodically appears. This short-living intrinsically connected to each burst. It vanishes once profiles fully flattened, and it reestablishes during recovery critical gradients reached new...
We study the Hall effect in diluted plasmas within two-fluids theory. Composed by two distinct species with opposite charge, such as electrons and ions fully ionised hydrogen, plasma is driven an electric field through a channel presence of transversal magnetic field. As consequence, separation charge induced producing potential difference. have found general relation for voltage function mass viscosity ratios, which converges to usual expression limit solid matter, i.e. when are much more...
We study magnetic reconnection events in a turbulent plasma within the two-fluid theory. By identifying diffusive regions, we measure rates as function of conductivity and current sheet thickness. have found that rate scales squared inverse sheet's thickness is independent aspect ratio region, contrast to other analytical, e.g. Sweet-Parker Petscheck, numerical models. Furthermore, while are also proportional square conductivity, ratios which exhibit values range $0.1-0.9$, not correlated...
A new Gas Puff Imaging (GPI) diagnostic has been installed on the TCV tokamak, providing two-dimensional insights into Scrape-Off-Layer (SOL) turbulence dynamics above, at and below magnetic X-point. detailed study in L-mode, attached, lower single-null discharges shows that statistical properties have little poloidal variations, while vast differences are present 2D behaviour of intermittent filaments. Strongly elongated filaments, just above X-point divertor far-SOL, show a good...
Abstract The analysis of turbulence in plasmas is fundamental fusion research. Despite extensive progress theoretical modeling the past 15 years, we still lack a complete and consistent understanding magnetic confinement devices, such as tokamaks. Experimental studies are challenging due to diverse processes that drive high-speed dynamics turbulent phenomena. This work presents novel application motion tracking identify track filaments plasmas, called blobs, high-frequency video obtained...
The analysis of turbulence in plasmas is fundamental fusion research. Despite extensive progress theoretical modeling the past 15 years, we still lack a complete and consistent understanding magnetic confinement devices, such as tokamaks. Experimental studies are challenging due to diverse processes that drive high-speed dynamics turbulent phenomena. This work presents novel application motion tracking identify track filaments plasmas, called blobs, high-frequency video obtained from Gas...