Experimental investigation of the origin of residual disturbances in turbulent MHD flows after laminarization

The problem of the strong velocity disturbances remaining after the laminarization of an electroconductive fluid flow in a transverse magnetic field was investigated experimentally. The turbulence intensities, two-point correlations, and energy spectra of the velocity pulsations were measured using two-electrode probes and hot-film sensors. The two hypotheses with regard to a physical explanation of the persistence of the disturbances were examined, and it was concluded that these disturbances are generated mainly at the entry of the flow into the magnetic-field region. An almost undisturbed laminarized flow was obtained by eliminating the entry effects.

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Rapid collapse of antiparallel magnetic field system of finite width by fast reconnexion

Journal of Plasma Physics ◽

10.1017/s002237780002314x ◽

1981 ◽

Vol 25 (2) ◽

pp. 309-321 ◽

Cited By ~ 3

Author(s):

Masayuki Ugai

Keyword(s):

Magnetic Field ◽

Plasma Flow ◽

Magnetic Energy ◽

Finite Width ◽

Field Region ◽

Field Reversal ◽

Return Current ◽

Magnetic Field Region ◽

Current Flows ◽

The Magnetic Field

The present computer experiment studies an explosive magnetic energy conversion in an antiparallel-fleid system of finite width where sheet current flows in the middle of the system and return current flows on both sides of the system. It is demonstrated that, initiated by local onset of anomalous resistivity, the global plasma flow grows so as to bring about the so-called fast reconnexion process that provides rapid magnetic flux transfer as well as rapid magnetic energy release. In the resulting configuration of fast reconnexion, the plasma flow drastically reverses its direction across the magnetic- field region, and the effective width of the magnetic-field region becomes rapidly reduced with time. It is found that the fast reconnexion suddenly decays when the front tip of the return-current region has just arrived at the field-reversal region.

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MAGNETIC DEPENDENCE OF HALL SIGN REVERSAL FOR Gd1-xPrxBa2Cu3O7-δ IN A VORTEX STATE

Modern Physics Letters B ◽

10.1142/s0217984902004251 ◽

2002 ◽

Vol 16 (22) ◽

pp. 853-860 ◽

Cited By ~ 3

Author(s):

V. DAADMEHR ◽

H. NAGHSHARA ◽

M. AKHAVAN

Keyword(s):

Magnetic Field ◽

High Temperature Superconductors ◽

Vortex State ◽

Complex Nature ◽

Field Region ◽

Sign Reversal ◽

Hall Resistivity ◽

Sign Change ◽

Magnetic Field Region ◽

The Magnetic Field

We have investigated the sign reversal of Hall effect in high-temperature superconductors in the vortex state as a function of temperature for several samples of Gd 1-x Pr x Ba 2 Cu 3 O 7-δ with 0.2 ≥ x ≥ 0 in a magnetic field of 0–2 T. Multiple sign reversals of Hall resistivity have been observed in under-doped and partially over-doped samples. The Gd 1-x Pr x Ba 2 Cu 3 O 7-δ sample with x = 0.1 shows double sign change in Hall resistivity with variation of magnetic field, and a single sign reversal with variation of temperature. While for the x = 0.15 and x = 0.2 samples, no sign reversal is observed, for the x < 0.1 sample, one sign change of Hall resistivity with temperature over the magnetic field region is observed. The tan (θ H ) also shows a similar double sign reversal of Hall resistivity. This can be related to the particle-hole asymmetry and the complex nature of the Fermi surface.

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

Scientific Reports ◽

10.1038/s41598-021-87651-8 ◽

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.

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Soliton locking phenomenon over finite magnetic field region in the monoaxial chiral magnet CrNb 3 S 6

Applied Physics Letters ◽

10.1063/5.0028910 ◽

2020 ◽

Vol 117 (23) ◽

pp. 232403

Author(s):

M. Ohkuma ◽

M. Mito ◽

Y. Kousaka ◽

T. Tajiri ◽

J. Akimitsu ◽

...

Keyword(s):

Magnetic Field ◽

Field Region ◽

Magnetic Field Region

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Heat Transfer to MHD Oscillatory Viscoelastic Flow in a Channel Filled with Porous Medium

Physics Research International ◽

10.1155/2012/879537 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Rita Choudhury ◽

Utpal Jyoti Das

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Porous Medium ◽

Radiative Heat ◽

Saturated Porous Medium ◽

Transverse Magnetic ◽

Viscoelastic Flow ◽

Viscoelastic Parameter ◽

Flow Parameters ◽

The Magnetic Field

The combined effect of a transverse magnetic field and radiative heat transfer on unsteady flow of a conducting optically thin viscoelastic fluid through a channel filled with saturated porous medium and nonuniform walls temperature has been discussed. It is assumed that the fluid has small electrical conductivity and the electromagnetic force produced is very small. Closed-form analytical solutions are constructed for the problem. The effects of the radiation and the magnetic field parameters on velocity profile and shear stress for different values of the viscoelastic parameter with the combination of the other flow parameters are illustrated graphically, and physical aspects of the problem are discussed.

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Вращение плазменной струи высокочастотными электромагнитными полями и ее использование для масс-сепарации

Журнал технической физики ◽

10.21883/jtf.2020.03.48936.257-19 ◽

2020 ◽

Vol 90 (3) ◽

pp. 482

Author(s):

Н.М. Горшунов ◽

Е.П. Потанин

Keyword(s):

Magnetic Field ◽

Spent Nuclear Fuel ◽

Transverse Magnetic ◽

Mhd Equations ◽

Direct Flow ◽

Fuel Component ◽

Product Flow ◽

Dipole Configuration ◽

Uranium Plutonium ◽

The Magnetic Field

Equations are obtained that describe the characteristics of the azimuthal motion and radial expansion of a plasma jet under the action of a rotating transverse magnetic field of a dipole configuration in a longitudinal static magnetic field. The analysis was carried out both in the multicomponent approximation and on the basis of MHD equations taking into account the Hall effect. Based on the obtained dependences of the azimuthal and radial ion velocities on the magnetic field values, the separation characteristics of the direct-flow plasma centrifuge are estimated for the separation of a two-component binary mixture simulating spent nuclear fuel. It was shown that the concentration of the heavy uranium-plutonium component in the product flow can be increased from the initial 96 to 99.8% with a fuel component extraction of 0.87.

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Spatial Temperature Profile in a Magnetised Capacitively Coupled Discharge

Walailak Journal of Science and Technology (WJST) ◽

10.48048/wjst.2019.4784 ◽

2018 ◽

Vol 16 (6) ◽

pp. 385-390

Author(s):

Shikha BINWAL ◽

Jay K JOSHI ◽

Shantanu Kumar KARKARI ◽

Predhiman Krishan KAW ◽

Lekha NAIR ◽

...

Keyword(s):

Magnetic Field ◽

Electron Temperature ◽

Temperature Profile ◽

Transverse Magnetic ◽

Capacitively Coupled ◽

Particle In Cell ◽

Cell Simulation ◽

Higher Temperature ◽

The Magnetic Field ◽

Emissive Probe

A floating emissive probe has been used to obtain the spatial electron temperature (Te) profile in a 13.56 MHz parallel plate capacitive coupled plasma. The effect of an external transverse magnetic field and pressure on the electron temperature profile has been discussed. In the un-magnetised case, the bulk region of the plasma has a uniform Te. Upon application of the magnetic field, the Te profile becomes non-uniform and skewed. With increase in pressure, there is an overall reduction in electron temperature. The regions adjacent to the electrodes witnessed a higher temperature than the bulk for both cases. The emissive probe results have also been compared with particle-in-cell simulation results for the un-magnetised case.

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Excitation And Ionization By Auroral Protons

Australian Journal of Physics ◽

10.1071/ph660309 ◽

1966 ◽

Vol 19 (3) ◽

pp. 309 ◽

Cited By ~ 30

Keyword(s):

Magnetic Field ◽

Energy Range ◽

Pitch Angle ◽

Proton Energy ◽

Ionization Rate ◽

Energy Spectra ◽

Proton Fluxes ◽

Atmospheric Ionization ◽

The Magnetic Field

Height distributions are presented for the atmospheric ionization rate and Balmer radiation resulting from precipitation of auroral protons. These results have been computed assuming proton fluxes with several different energy spectra and pitch-angle distributions about the magnetic field, the total proton energy range being restricted to 1-1000 keY.

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Теплообмен при смешанной конвекции расплава соли в присутствии магнитных полей

Письма в журнал технической физики ◽

10.21883/pjtf.2019.10.47752.17507 ◽

2019 ◽

Vol 45 (10) ◽

pp. 27

Author(s):

И.А. Беляев ◽

Д.А. Бирюков ◽

А.В. Котляр ◽

Е.А. Белавина ◽

П.А. Сардов ◽

...

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Temperature Fluctuations ◽

Reynolds Numbers ◽

Transverse Magnetic ◽

Statistical Characteristics ◽

Transfer Coefficients ◽

Gravitational Flow ◽

Heat Transfer Coefficients ◽

The Magnetic Field

The results of an experimental study of the salt melt downflow in a uniformly heated pipe under the influence of a strong transverse magnetic field are presented. The changes of heat transfer coefficients and statistical characteristics of temperature fluctuations under the influence of the magnetic field are investigated. The peculiarities of the transition of the viscous-gravitational flow in the viscous-inertial-gravitational flow at Reynolds numbers (Re=3000-5000) under the influence of the magnetic field (Ha=17) were studied.

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