A5070989875- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Fusion materials and technologies
- Solar and Space Plasma Dynamics
- Laser-Plasma Interactions and Diagnostics
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Plasma Diagnostics and Applications
- Metal and Thin Film Mechanics
- Nuclear Materials and Properties
- Advanced materials and composites
- Atomic and Molecular Physics
- Atomic and Subatomic Physics Research
- Astronomical Observations and Instrumentation
- Physics of Superconductivity and Magnetism
- High-pressure geophysics and materials
- Laser-induced spectroscopy and plasma
- Theoretical and Computational Physics
- Nuclear reactor physics and engineering
- Dust and Plasma Wave Phenomena
- Intermetallics and Advanced Alloy Properties
- Geomagnetism and Paleomagnetism Studies
- Oceanographic and Atmospheric Processes
- Metallurgical Processes and Thermodynamics
- Rare-earth and actinide compounds
Southwest Jiaotong University
2017-2024
Northwest University
2024
Southwestern Institute of Physics
2014-2017
Forschungszentrum Jülich
2003-2016
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2016
Xihua University
2016
Tsinghua University
2016
CEA Cadarache
2016
Zhejiang University
2016
Royal Military Academy
2003-2013
Abstract Since the last IAEA Fusion Energy Conference in 2018, significant progress of experimental program HL-2A has been achieved on developing advanced plasma physics, edge localized mode (ELM) control physics and technology. Optimization confinement performed. In particular, high- β N H-mode plasmas exhibiting an internal transport barrier have obtained (normalized pressure reached up to 3). Injection impurity improved confinement. ELM using resonance magnetic perturbation or injection a...
In the first four years of LHD experiment, several encouraging results have emerged, most significant which is that MHD stability and good transport are compatible in inward shifted axis configuration. The observed energy confinement at this optimal configuration consistent with ISS95 scaling an enhancement factor 1.5. over smaller heliotron devices attributed to high edge temperature. We find plasma average beta 3% stable configuration, even though theoretical conditions Mercier modes...
Recent experimental results in the Large Helical Device have indicated that a large pressure gradient can be formed beyond stability criterion for Mercier (high-n) mode. While against an interchange mode is violated inward-shifted configuration due to enhancement of magnetic hill, neoclassical transport and confinement high-energy particle are, contrast, improved by this inward shift. Mitigation unfavourable effects MHD instability has led significant extension operational regime....
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 Chinese First Quasi-axisymmetric Stellarator (CFQS) is a joint project of international collaboration. It designed and fabricated by Southwest Jiaotong University (SWJTU) in China National Institute for Fusion Science (NIFS) Japan. In this work, plasma boundary modular-coil system the CFQS have been optimized via scan magnetic configurations with various aspect ratios. present target parameters are as follows: toroidal periodic number, ratio, field strength major radius 2, 4.0, 1.0 T, m,...
This paper generally compares the essential features between tokamaks and stellarators, based on previous review work individually made by authors several specific topics, such as theories, bulk plasma transport edge divertor physics, along with some recent results. It aims at summarizing main results conclusions regard to advantages disadvantages in these two types of magnetic fusion devices. The comparison includes basic configurations, magnetohydrodynamic (MHD) instabilities, operational...
Time and space resolved measurements of electrostatic Reynolds stress, radial electric field E(r), plasma rotations have been performed across the transition to improved Ohmic confinement in Hefei Tokamak-6M (HT-6M). The first experimental evidence correlation between enhanced stress gradient poloidal flow acceleration edge is presented. results indicate that turbulence-induced might be dominant mechanism create sheared which may further trigger transition.
As in many of today's tokamaks, plasma start-up ITER will be performed limiter configuration on either the inner or outer midplane first wall (FW). The massive, beryllium armored FW panels are toroidally shaped to protect panel-to-panel misalignments, increasing deposited power flux density compared with a purely cylindrical surface. chosen shaping should thus optimized for given radial profile parallel heat flux, scrape-off layer (SOL) ensure optimal spreading. For plasmas limited this is...
The radial profiles of perpendicular flows in the presence magnetic island were firstly measured HL-2A tokamak by hopping work frequency Doppler backward scattering reflectometer system along with a two-dimensional electron cyclotron emission imaging diagnostic identifying locations. It has been observed that across O-point cut flow is quite small at center and strongly enhanced around boundary island, resulting large increase shear outer half while X-point almost flat whole region....
The Chinese First Quasi-axisymmetric Stellarator (CFQS) is a new quasi-axisymmetric experimental device planned for construction at South West Jiaotong University (SWJTU), China. This joint project of the National Institute Fusion Science (NIFS) and SWJTU. present paper discusses equilibrium configuration CFQS with major radius 1.0 m, toroidal magnetic field strength T, an aspect ratio 4.0. As stellarator, tokamak-like bootstrap current expected. magnitude was estimated by BOOTSJ code. Next,...
Abstract This study used molecular dynamics software LAMMPS to simulate the surface binding energy of W1-xMox (x=0,0.9375,0.875,0.75,0.625,0.5) alloy (110) surface. The effect thermal vibration, model size, step size and temperature for comprehensively considered. Finally, reference values W-Mo alloys with different concentrations were obtained, it was found that, within simulation range, as Mo concentration increased, W atoms increased from 11.661±0.017 eV 12.058±0.047 eV, while decreased...
Recently, a European transport project has been carried out among several fusion devices for studying the possible link between mean radial electric field ( E r ), long-range correlation (LRC) and edge bifurcations in plasmas. The main results reported this paper include: (i) discovery of low-frequency LRCs potential fluctuations which are amplified during development using electrode biasing spontaneous sheared flows stellarators tokamaks. Evidence nonlocal energy transfer geodesic acoustic...
The oscillations of poloidal plasma flows induced by radially sheared zonal are investigated newly developed correlation Doppler reflectometers in the HL-2A tokamak. non-disturbing diagnostic allows one to routinely measure rotation velocity turbulence, and hence radial electric field fluctuations. With reflectometers, a three-dimensional spatial structure geodesic acoustic mode (GAM) is surveyed, including symmetric feature toroidal Er fluctuations, dependence GAM frequency on temperature...
Strong resonant and non-resonant internal kink modes (abbreviated as RKs NRKs, respectively), which are also called fishbones, observed on HL-2A tokamak with high-power ECRH + ECCD− (or ECRH) ECCD+, respectively. ('Resonant' derives from the existence of q = 1 surface (the surface), 'non-resonant' originates absence (). ECCD+ mean driving direction energetic electrons is same opposite to plasma current, respectively.) RK has features periodic strong bursting amplitude rapid chirping-down...
An internal transport barrier (ITB) was observed in the electron temperature profile Large Helical Device [O. Motojima et al., Phys. Plasmas 6, 1843 (1999)] with a centrally focused intense cyclotron resonance microwave heating. Inside ITB core improved, and high temperature, exceeding 10 keV low density, achieved collisionless regime. The formation of electron-ITB is correlated neoclassical root strong radial electric field determined by ambipolar flux. direction tangentially injected...
Bolometer diagnostics are installed on the Large Helical Device (LHD) to provide measurements of total (broad spectrum) electromagnetic radiation emitted by plasma. Three types detectors used: resistive metal film bolometers, absolute extreme ultraviolet photodiodes and infrared imaging video bolometers. Details installation in LHD given for each type detector. The detector calibration, data analysis tomography techniques described compared sample results shown.
The influence of the magnetic ergodization on edge turbulence and turbulence-induced transport has been investigated by Langmuir probes in TEXTOR under three different static DED configurations. Common features are observed. With DED, equilibrium profiles altered resultant positive Er is agreement with modelling. In ergodic zone, potential fluctuations strongly reduced local turbulent flux changes direction from radially outwards to inwards. same properties profoundly modified energy...
Multi-scale interactions have been observed recently in the HL-2A core NBI plasmas, including synchronous coupling between kink mode and tearing mode, nonlinear couplings of TAE/BAE TM near surface, AITG/KBM/BAE high-frequency turbulence. Experimental results suggest that several can exist simultaneously, Alfvenic fluctuations an important contribution to turbulence spectra, reveal electromagnetic character. via modulation process maybe enhance plasma transport trigger sawtooth-crash onset.
In HL-2A, the characteristics of edge plasma instabilities and their effects on dynamical evolution pedestal in H-mode plasmas have been investigated. region with steep pressure gradient, a quasi-coherent mode (QCM) has observed density fluctuations frequency range 50–100 kHz. It appears during localized (ELM)-free period after L–H transition prior to first ELM. A threshold gradient identified for excitation this mode. The QCM can also be inter-ELM periods. is excited early period,...