A5050666492- Magnetic confinement fusion research
- Fusion materials and technologies
- Plasma Diagnostics and Applications
- Ionosphere and magnetosphere dynamics
- Laser-Plasma Interactions and Diagnostics
- Particle accelerators and beam dynamics
- Nuclear Materials and Properties
- Nuclear reactor physics and engineering
- Superconducting Materials and Applications
- Nuclear Physics and Applications
- Metal and Thin Film Mechanics
- Atomic and Subatomic Physics Research
- Advanced materials and composites
- Cold Fusion and Nuclear Reactions
- Plasma Applications and Diagnostics
- Solar and Space Plasma Dynamics
- Recycling and Waste Management Techniques
- Time Series Analysis and Forecasting
- Ion-surface interactions and analysis
- Laser-induced spectroscopy and plasma
- Thermochemical Biomass Conversion Processes
- Electrohydrodynamics and Fluid Dynamics
- Glass properties and applications
- Atomic and Molecular Physics
- Fluid Dynamics and Turbulent Flows
Ghent University
2015-2024
Ghent University Hospital
2009-2023
Moscow Engineering Physics Institute
2016-2021
Moscow Power Engineering Institute
2019-2021
Japan External Trade Organization
2016
Royal Military Academy
1992-2012
Forschungszentrum Jülich
1986-2011
Max Planck Institute for Plasma Physics
1993-2011
Czech Academy of Sciences, Institute of Plasma Physics
2001-2008
Heinrich Heine University Düsseldorf
2006
Predictions of observable properties by density-functional theory calculations (DFT) are used increasingly often experimental condensed-matter physicists and materials engineers as data. These predictions to analyze recent measurements, or plan future experiments in a rational way. Increasingly more scientists these fields therefore face the natural question: what is expected error for such first-principles prediction? Information experience about this question implicitly available...
Geodesic acoustic modes (GAMs) were investigated on the T-10 tokamak using heavy ion beam probe, correlation reflectometry and multipin Langmuir probe diagnostics. Regimes with Ohmic heating on- off-axis ECRH studied. It was shown that GAMs are mainly potential oscillations. Typically, power spectrum of oscillations has form a solitary quasi-monochromatic peak contrast range 3–5. They manifestation torsional plasma poloidal wavenumber m = 0, called zonal flows. The frequency changes in...
Edge radial electric fields were induced in the edge of TEXTOR tokamak by means a polarization electrode order to study their influence on plasma profiles and its confinement. The studies include generation H-mode behaviour with either positive or negative polarity. Particle confinement (τp) deuterium impurity ions as well energy (τE) are investigated. For which remain below threshold for L-H transition, an interesting regime reduced particle without noticeable loss is found. A strong...
Experiments in the tokamaks TEXTOR, CASTOR, T-10 and ISTTOK, as well reversed field pinch RFX have provided new complementary evidence on physics of universal mechanism E×B velocity shear stabilization turbulence, concomitant transport barrier formation radial conductivity by using various edge biasing techniques.
Abstract Samples of tungsten and tungsten–tantalum alloy (with 5 mass per cent Ta) were exposed to high-flux deuterium plasma at different fluences. The surface modification was studied with scanning electron microscopy, retention measured by thermal desorption spectroscopy (TDS). In the high fluence range ∼3.5 × 10 26 –10 27 m -2 , multiple large-size blisters are formed on W surface, while W–Ta considerably smaller in size number. Deuterium this found be systematically higher than W–Ta....
The conversion of waste to energy is an essential process in the Middle East, especially Saudi Arabia, where it plays a crucial role management. annual analysis decomposition hazards landfills city Makkah showed that they ranged from 168,000 Mg 1994 297,000 2022. emission costs pollution 4 million 7 number gas emissions plastic accumulating analyzed landfill has increased 128,000 227,000 thermal plasmas used were produced by air plasma torches, which are part reactors. operational...
Stationary high energy confinement is observed on TEXTOR-94 for times limited only by the flux swing of transformer using strong edge radiation cooling. Necessary tools are feedback control radiated power and plasma content. At highest densities obtained (up to 1.2 Greenwald limit), exceeds edge-localized-mode-free H-mode scaling ITERH93-P more than 20%. β limits reached with fH89/qa≈0.6. No detrimental effect seeded impurity seen. These discharges meet many conditions necessary a fusion...
Results from the first measurements of a core plasma poloidal rotation velocity (upsilontheta) across internal transport barriers (ITB) on JET are presented. The spatial and temporal evolution ITB can be followed along with upsilontheta radial profiles, providing very clear link between location steepest region ion temperature gradient localized spin-up upsilontheta. an order magnitude higher than neoclassical predictions for thermal particles in region, contrary to close agreement found...
H mode behaviour is usually linked to the existence of radial electric fields or their shear at edge tokamaks. The mechanisms are investigated by which such induced in plasma and profile shaping obtained when currents imposed electrode polarization. Earlier detailed experimental field measurements successfully compared with a theoretical conductivity model neoclassical non-ambipolar transport mobility through ion-neutral collisions predominant. Strong viscosity bulk allows significant...
The interaction between the ion cyclotron resonance heating and plasma edge is a vast interlinked domain: affects radio frequency edge. This is-in view of relation overall properties performance-of utmost importance. paper gives an overview topic, emphasizing basic concepts recent results. identification sheath rectification mechanism as main cause for influence RF on edge, has permitted better understanding this domain significant progress in avoidance effects.
An emissive probe has been used in the edge region of CASTOR tokamak order to test possibility direct measurements plasma potential. The difference between floating potential a cold and that an found be approximately 1.3 times electron temperature, which is less than predicted by theory. Several possible reasons explain this discrepancy are offered, such as secondary emission, uncertainties ion different collecting areas for electrons ions, etc. impact space charge formed emitted also discussed.
During the past centuries, industrial processes and energy conversion plants have shown no or little care for environmental quality. The result is a huge accumulation of pollution hazardous by-products, left as heritage present future generations. Recuperation by-products thermal not only motivated by cost saving, but also resource saving considerations. Environmental awareness more than staying within lines existing regulations.
An overview is presented of recent results on the creation electric fields in edge limiter or divertor tokamaks. The practical implementation and theoretical basis several schemes, generating radial and/or poloidal fields, are outlined. manipulation scrape-off-layer profiles control particle exhaust discussed. Contributions biasing experiments to H-mode physics highlighted. Some prospects for next generation tokamaks finally given.
Dedicated experiments have been carried out at the TEXTOR tokamak in biasing-induced improved confinement regimes using Langmuir probe and GPI measurements. The results show first evidence for intimate interaction among sheared flows, eddy structures, Reynolds stress, zonal ambient fluctuations during a transition to an confinement. flows impose dynamic effects on turbulence resulting generation of stress eventually suppression background fluctuation levels via nonlinear energy transfer...
The effect of severe plastic deformation on the deuterium retention in tungsten exposed to high-flux low-energy plasma (flux ∼ 1024 D/m2/s, energy 50 eV, and fluence up 3 × 1026 D/m2) at generator Pilot-PSI was studied by thermal desorption spectroscopy scanning electron microscopy. spectra both reference plastically deformed samples were deconvolved into three contributions attributed detrapping from dislocations, deuterium-vacancy clusters, pores, respectively. induced deformation,...
Plasma turbulent transport was investigated at the edge of GOLEM tokamak. For this purpose, ion saturation current fluctuations were measured by means Langmuir probes. stabilization not activated during discharges under study. Non-Gaussian behavior is observed, which indicates presence coherent structures. Study radial dependence statistical and temporal characteristics allows to conclude that non-elongated blob-like structures with comparable poloidal size should govern plasma
Positive radial electric fields have been created at the edge of TEXTOR tokamak plasma using an electrode. The field induces a thin (δr∼1.5 cm), E × B driven layer rotating poloidally 12-20 km/s and featuring high shear. Concomitant changes in density poloidal fluctuations their cross-phase shear result suppression turbulent particle transport, even low strength. Temperature are reduced, resulting diminished heat flux. As transport is quenched, confinement time τp increases by factor 2...
The first results of the Dynamic Ergodic Divertor in TEXTOR, when operating m/n=3/1 mode configuration, are presented. deeply penetrating external magnetic field perturbation this configuration increases toroidal plasma rotation. Staying below excitation threshold for m/n=2/1 tearing mode, rotation is always direction current, even if projection rotating opposite direction. observed consistent with a radial electric field, generated by an enhanced electron transport ergodic layers near...