Hall Effect, or Hyperbolic Magnetohydrodynamics, HMHD

1987 ◽  
Vol 42 (9) ◽  
pp. 917-921 ◽  
Author(s):  
E. A Witalis
Keyword(s):  
Magnetic Field ◽  
Hall Effect ◽  
Boundary Region ◽  
Plasma Boundary ◽  
Magnetic Fusion ◽  
Plasma Edge ◽  
Plasma Confinement ◽  
Third Law ◽  
Magnetic Bottle ◽  
Density Plasma

The MHD theory of present magnetic fusion research is briefly reviewed with emphasis on its mathematically diffusive character. The importance of retaining the Hall effect term, neglected in ideal or resistive MHD theory, is stressed. Elliptic MHD theory is critically dismissed. The Hall effect, or Hyperbolic, MagnetoHydro-Dynamics, HMHD, is shown to follow as the consequence of a revision of plasma electrodynamics so as to account for the fundamental plasma quasineutrality. The non-validity of Newton’s third law in charged particle contexts is then central. Previously poorly understood phenomena, such as plasma edge effects and magnetic field line reconnection are found to be inherent properties in this HMHD plasma description. The “magnetic bottle” principle for high density plasma confinement is shown to be physically unsound because there will exist a no-confinement plasma boundary region with HMHD theory properties. Arguments for non-thermal fusion, provided by HMHD theory, are given.

scholarly journals Ripple transport and neoclassical diffusion in IR-T1 tokamak

2019 ◽  
Vol 14 (1) ◽  
pp. 93-99
Author(s):  
M. Hosseininejad ◽  
M. Ghoranneviss ◽  
M. K. Salem
Keyword(s):  
Magnetic Field ◽  
Diffusion Coefficient ◽  
Heat Conductivity ◽  
Fusion Reactor ◽  
Particle Removal ◽  
Plasma Edge ◽  
Plasma Confinement ◽  
Particle Trapping ◽  
Discontinuous Nature ◽  
The Magnetic Field

AbstractIn tokamaks, small variations in the magnetic field create ripple. The discontinuous nature of the magnetic field coils in an axisymmetric torus conduces to additional particle trapping, and it is responsible for an additional neoclassical diffusion. Ripples also reduce the particle removal efficiency and disturb plasma confinement and cause constraints in the design of magnet of fusion reactor. Therefore, it is quite important to include the ripple for the design of plasma edge components. Herein, several considerations are taken into account to calculate and evaluate the diffusion coefficient and ion heat conductivity in ripple transport and also to compare it with neoclassical mode.

Modifications of plasma edge electric field and confinement properties by limiter biasing on the KT-5C tokamak

1995 ◽  
Vol 54 (3) ◽  
pp. 393-400 ◽  
Author(s):  
Hui Gao ◽  
Kan Zhai ◽  
Yi-Zhi Wen ◽  
Shu-De Wan ◽  
Gui-Ding Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Electron Temperature ◽  
Particle Flux ◽  
Plasma Potential ◽  
Edge Plasma ◽  
Plasma Edge ◽  
Confinement Time ◽  
Plasma Confinement ◽  
Particle Confinement

Experiments using a biased multiblock limiter in the KT-5C tokamak show that positive biasing is more effective than negative biasing in modifying the edge electric field, suppressing fluctuations and improving plasma confinement. The biasing effect varies with the limiter area, the toroidal magnetic field and the biasing voltage. By positive biasing, the edge profiles of the plasma potential, the electron temperature and the density become steeper, resulting in a reduced edge particle flux, an increased global particle confinement time and lower fluctuation levels of the edge plasma.

scholarly journals Enhanced X-ray emission arising from laser-plasma confinement by a strong transverse magnetic field

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Evgeny D. Filippov ◽  
Sergey S. Makarov ◽  
Konstantin F. Burdonov ◽  
Weipeng Yao ◽  
Guilhem Revet ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Transverse Magnetic ◽  
Radiative Properties ◽  
Magnetic Field Direction ◽  
Solid Target ◽  
Total Plasma ◽  
Plasma Confinement ◽  
X Ray ◽  
Magnetic Compression ◽  
The Magnetic Field

AbstractWe analyze, using experiments and 3D MHD numerical simulations, the dynamic and radiative properties of a plasma ablated by a laser (1 ns, 10$$^{12}$$ 12 –10$$^{13}$$ 13 W/cm$$^2$$ 2 ) from a solid target as it expands into a homogeneous, strong magnetic field (up to 30 T) that is transverse to its main expansion axis. We find that as early as 2 ns after the start of the expansion, the plasma becomes constrained by the magnetic field. As the magnetic field strength is increased, more plasma is confined close to the target and is heated by magnetic compression. We also observe that after $$\sim 8$$ ∼ 8  ns, the plasma is being overall shaped in a slab, with the plasma being compressed perpendicularly to the magnetic field, and being extended along the magnetic field direction. This dense slab rapidly expands into vacuum; however, it contains only $$\sim 2\%$$ ∼ 2 % of the total plasma. As a result of the higher density and increased heating of the plasma confined against the laser-irradiated solid target, there is a net enhancement of the total X-ray emissivity induced by the magnetization.

scholarly journals The quantum Hall effect in the absence of disorder

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Kyung-Su Kim ◽  
Steven A. Kivelson
Keyword(s):  
Magnetic Field ◽  
Hall Effect ◽  
Quantum Hall Effect ◽  
Finite Interval ◽  
Quantum Hall ◽  
Wigner Crystal ◽  
Quasi Particle ◽  
Hall Conductance ◽  
Finite Extent

AbstractIt is widely held that disorder is essential to the existence of a finite interval of magnetic field in which the Hall conductance is quantized, i.e., for the existence of “plateaus” in the quantum Hall effect. Here, we show that the existence of a quasi-particle Wigner crystal (QPWC) results in the persistence of plateaus of finite extent even in the limit of vanishing disorder. Several experimentally detectable features that characterize the behavior in the zero disorder limit are also explored.

The Study of p-n and Schottky Junction for Magnetodiode

2011 ◽  
Vol 378-379 ◽  
pp. 663-667 ◽  
Author(s):  
Toempong Phetchakul ◽  
Wittaya Luanatikomkul ◽  
Chana Leepattarapongpan ◽  
E. Chaowicharat ◽  
Putapon Pengpad ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electrical Properties ◽  
Simulation Model ◽  
Hall Effect ◽  
Schottky Junction ◽  
Field Sensitivity ◽  
Field Response ◽  
Type Semiconductor ◽  
Simulation Results ◽  
P Type

This paper presents the simulation model of Dual Magnetodiode and Dual Schottky Magnetodiode using Sentaurus TCAD to simulate the virtual structure of magneto device and apply Hall Effect to measure magnetic field response of the device. Firstly, we use the program to simulate the magnetodiode with p-type semiconductor and aluminum anode and measure electrical properties and magnetic field sensitivity. Simulation results show that sensitivity of Dual Schottky magnetodiode is higher than that of Dual magnetodiode.

Quantized Hall effect in gated AlGaAs/GaAs heterostructures: Localization as a function of number density and magnetic field

1986 ◽  
Vol 59 (10) ◽  
pp. 691-695 ◽  
Author(s):  
L.X. He ◽  
K.P. Martin ◽  
R.J. Higgins ◽  
J.S. Brooks ◽  
P.R. Jay ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Hall Effect ◽  
Number Density

Approaching to the ideal condition of plasma confinement by applying external resonant fields in IR-T1 tokamak

2015 ◽  
Vol 81 (3) ◽  
Author(s):  
Sakineh Meshkani ◽  
Mahmood Ghoranneviss ◽  
Mansoureh Lafouti
Keyword(s):  
Magnetic Field ◽  
Turbulent Transport ◽  
Edge Plasma ◽  
Ideal Condition ◽  
Plasma Confinement ◽  
Applied Bias ◽  
Inverse Results ◽  
Electric And Magnetic Field ◽  
Helical Magnetic Field ◽  
The Ideal

For understanding the effect of resonant helical magnetic field (RHF) and bias on the edge plasma turbulent transport, the radial and poloidal electric field (Er, EP), poloidal and toroidal magnetic field (BP, Br) were detected by the Langmuir probe, magnetic probe and diamagnetic loop. The poloidal, toroidal and radial velocity (VP, Vr, Vt) can be determined from the electric and magnetic field. In the present work, we have investigated the effect of the magnitude of bias (Vbias = 200v, Vbias = 320v) on Er, EP, BP, Bt, VP, Vr, Vt. Moreover, we applied RHF with L = 2, L = 3 and L = 2 and 3 and investigate the effect of the helical windings radius on above parameters. Also, the experiment was repeated by applying the positive biasing potentials and RHF's simultaneously. The results show that by applying bias to the plasma at t = 15 msec at r/a = 0.9, Er, BP and Bt increase while EP decreases. The best modification occurs at Vbias = 200v. By applying RHF to the plasma, both the electric and magnetic field vary. Er reaches the highest in the presence of RHF with L = 3. The same results are obtained for BP, Bt, VP and Vt. While the inverse results are obtained for EP and Vr. Finally, RHF and bias are applied simultaneously to the plasma. With applied bias with Vbias = 200v and RHF with L = 2 and 3, we reach to the ideal circumstance. The same results obtain in the situation with Vbias = 320v and RHF with L = 2 and 3.

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