A5061422836- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Laser-Plasma Interactions and Diagnostics
- Solar and Space Plasma Dynamics
- Particle accelerators and beam dynamics
- Dynamics and Control of Mechanical Systems
- Physics of Superconductivity and Magnetism
- Electromagnetic Launch and Propulsion Technology
- Fluid Dynamics Simulations and Interactions
- Fusion materials and technologies
- Laser-induced spectroscopy and plasma
- Dust and Plasma Wave Phenomena
- Theoretical and Computational Physics
- earthquake and tectonic studies
- Superconducting Materials and Applications
- Nanocluster Synthesis and Applications
- Ocean Waves and Remote Sensing
- Congenital heart defects research
- Metal-Organic Frameworks: Synthesis and Applications
- RNA modifications and cancer
- Geomagnetism and Paleomagnetism Studies
- Astronomical Observations and Instrumentation
- Landslides and related hazards
- Polyoxometalates: Synthesis and Applications
- Guidance and Control Systems
Southwestern Institute of Physics
2014-2023
Guangxi Medical University
2019
First Affiliated Hospital of GuangXi Medical University
2019
Liaoning Shihua University
2017
University of California, Irvine
2007-2008
The trapped electron modes (TEMs) are numerically investigated in toroidal magnetized hydrogen, deuterium and tritium plasmas, taking into account the effects of impurity ions such as carbon, oxygen, helium, tungsten others with positive negative density gradients rigorous integral eigenmode equation. on TEMs detail. It is shown that have substantially-destabilizing (stabilizing) isotope plasmas for (), opposite to case ion temperature gradient (ITG) driven modes. Detailed analyses mass...
The finite Larmor radius (FLR) effects play an important role in determining the threshold and growth rate of mirror instability. In this study, a general dispersion relation mode with FLR is derived by using gyrokinetic theory. It shows that both coupling to slow sound wave are stabilizing. A particle simulation code has been developed for compressible magnetic turbulence driven Results linear agree well analytic relation.
Mechanism of the nonlinear saturation compressible electromagnetic mirror instability is studied using gyrokinetic particle simulation. Phase‐space trapping due to force found be dominant mechanism in simulation a single mode with relatively weak drive. At saturation, phase‐space island distribution function formed. The oscillation frequency saturated perturbation amplitude close bounce trapped particles, which comparable linear growth rate mode. Scaling consistent onset trapping. With...
The stability and performance of tokamak plasmas are routinely limited by various magneto-hydrodynamic instabilities, such as neoclassical tearing modes (NTMs). This paper presents a rather simple method to control the NTMs in real time (RT) on tokamak, including principle feedback approach for RT suppression stabilization NTMs. system combines Mirnov, electron cyclotron emission, soft X-ray diagnostics used determining NTM positions. A methodology fast detection 2/1 or 3/2 positions with...
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation G. Z. Hao, Y. Q. Liu, A. K. Wang, M. Xu, H. P. Qu, X. D. Peng, J. Qiu; Resistive wall tearing mode generated finite net electromagnetic torque in a static plasma. Phys. Plasmas 1 January 2014; 21 (1): 012503. https://doi.org/10.1063/1.4861376 Download citation file: Ris (Zotero) Reference Manager EasyBib...
Abstract Direct causality analysis of the multi-scale interactions among macro-scale tearing mode (TM), meso-scale geodesic acoustic (GAM) and small-scale turbulence in edge plasma HL-2A tokamak utilizing transfer entropy (TE) method is reported. Experimental results have demonstrated that ( m / n ) = (2/1) (with being poloidal toroidal numbers, respectively) TM modulates with frequency range f 50–150 kHz GAM mainly higher frequencies. The has both amplitude phase modulation on energy while...
Abstract Statistical spectral features of the dependence geodesic acoustic modes (GAMs) and their nonlinear couplings with ambient turbulence on magnetic island (MI) width ( W ) in edge region HL-2A tokamak plasmas are analyzed. Experimental observations have indicated that modulation influence as well strength interactions between GAMs generally shows a gradual decay while MIs latter increased simultaneously MI becomes larger. The mainly reduce potential fluctuations, whereas changes...
Abstract The turbulent transport properties and dynamics of zonal flows (ZFs) in the presence fast ions (FIs) are investigated for a typical internal barrier (ITB) plasma based on gyrokinetic approach, focusing role FI temperature effects toroidal rotation, including E × B rotational shear, parallel velocity gradient (PVG) as well rotation itself. Linear GENE simulations have shown that core ITB HL-2A is dominated by ion (ITG) modes trapped electron (TEMs), where former stabilized FIs...
The neoclassical toroidal plasma viscosity torque and electromagnetic torque, generated by tearing mode (TM) in a plasma, are numerically investigated using the MARS-Q code [Liu et al., Phys. Plasmas 20, 042503 (2013)]. It is found that an initially unstable can intrinsically drive flow resulting steady state solution, absence of external momentum input magnetic field perturbation. saturated order 0.5%ωA at q=2 rational surface considered case, with q ωA being safety factor Alfven frequency...
The neoclassical polarization current, which can be generated by a time-dependent electric field resulting from magnetic island rotation, is believed to play an important role in the initial stage of tearing mode (NTM) evolution tokamak plasmas. In previous analytical description current contribution NTMs limit low collision frequency (νii≪εω, νii ion frequency, ε inverse aspect ratio, and ω propagation plasma rest frame), width islands has been assumed much larger than finite-banana-width...
The characteristics of zonal flows (ZFs) in ion temperature gradient (ITG) turbulence during the formation internal transport barrier (ITB) have been investigated by nonlinear gyrokinetic simulations for HL-2A tokamak experiment. turbulent heat and flow dynamics are local limit a neutral beam heated L-mode plasma. Linear stability analyses shown that maximum growth rate, γmax, is decreased across whole confinement region ITB although critical parameter, ηi, increased, which identified to be...
We numerically investigate the effects of ion-to-electron temperature ratio T i / e and gradient η on resistive ballooning modes (RBMs) under tokamak edge plasma conditions. The results show that growth rates RBMs exhibit characteristic a quite broad poloidal wavenumber spectrum in cold ion limit. rate becomes narrower peak shifts from short to long wavelength side with increasing . electron has very weak effect stability RBMs. However, have strong stabilizing short-wavelength RBMs, while...
Resistive drift wave instability is investigated numerically in tokamak edge plasma confined by sheared slab magnetic field geometry with an embedded island. The focus on the structural characteristics of eigenmode inside island, where density profile tends to be flattened. A transition dominant occurs around a critical island width wc. For thin islands below wc, two global long wavelength eigenmodes approximately same growth rate but different eigenfrequency are excited, which stabilized...
A self-organized criticality model of a thermal sandpile is formulated for the first time to simulate dynamic process with interaction between avalanche events on fast scale and diffusive transports slow scale. The main characteristics are that both particle energy avalanches sand grains considered simultaneously. Properties intermittent transport improved confinement analyzed in detail. results imply phenomenon such as blobs low mode well edge localized modes high observed tokamak...
Abstract This paper reports the verification and validation of a new gyrokinetic (GK) code, numerical Lie transform (NLT), for electrostatic turbulence simulation in tokamak plasmas. Based on standard cyclone base case (CBC), NLT has been verified against two typical GK codes, toroidal code (GTC) experiment tokamak, by simulating ion temperature gradient mode trapped electron mode. The linear dispersion relation structure agree well among all these codes. In nonlinear simulation, time...
Profiles of the ion density and bootstrap current in vicinity magnetic islands are investigated based on first principles gyro-kinetic particle simulation via toroidal code. The physics recovery gradient inside various collision regimes is discussed. Simulation results show that for small islands, can survive island due to combination effect both banana-orbit width trapped ions drift-orbit displacement passing ions. It suggested pressure may play a more important role reduction driving force...
A simple and direct theoretical method has been proposed to investigate the so-called ion-banana-orbit-width (IBW) effect on bootstrap current in region of magnetic islands generated by neoclassical tearing mode (NTM). The result shows that, when IBW approaches island width, (ion) can be partly restored inside while pressure profile is flattened. This lead reduction drive NTM. strength NTM related safety factor inverse aspect ratio rational surface.
The loss of bootstrap current inside magnetic island plays a dominant role in driving the neoclassical tearing mode (NTM) instability tokamak plasmas. In this work, we investigate finite-banana-width (FBW) effect on profile ion vicinity via an analytical approach. results show that even if pressure gradient vanishes island, can partly survive due to FBW effect. efficiency is higher when width becomes smaller. Nevertheless, comparable FBW, unperturbed cannot be largely recovered by effect,...
A collisional multi-ion-species fluid model is developed for the description of drift-resistive-inertial ballooning modes (DRIBMs) with collision rates calculated depending on Spitzer–Härm transport coefficients. Numerical results have shown that impurity effect linear stability DRIBM and corresponding strongly depends species, fraction fz (fz = nz/ne, where nz ne are electron densities, respectively), density gradient (R/Lnz), type driving force DRIBM. The driven (εn-RBM) usually stabilized...
In the previous analytical description of neoclassical polarization current effect on tearing modes (NTMs), it is usually assumed that magnetic island much larger than finite-ion-banana-width (FBW). This assumption questionable when experimentally observed seed width NTMs comparable to FBW. We introduce a simple and direct theoretical method investigate FBW contribution NTM evolution in collisional plasmas. The results show that, can strongly modify profile near separatrix, thus weaken its...
Abstract Turbulent transport and zonal flow (ZF) dynamics in the mixed kinetic ballooning mode (KBM) ion temperature gradient (ITG) dominated turbulence states are analyzed by gyrokinetic simulations based on experimental observations of KBMs HL-2A Internal Transport Barrier (ITB) plasmas with weak magnetic shear configuration. Results have shown that ITGs main candidates for turbulent inclusion fast ions (FIs) can destabilize both instabilities, which is resulted decrease parameter α MHD...
Past work has introduced that the neoclassical polarization drift of passing ion is in same direction as trapped ion. Here, based on model single particle motion, our analytical results indicate drifts and ions are opposite directions without collision considered. This helpful to easily understand previous expression collisionless current kinetic theories, which only a small quantity order O(ε3/2) compared banana regime.