Turbulent heating studies on STOR-I

1983 ◽  
Vol 61 (2) ◽  
pp. 147-155 ◽  
Author(s):  
C. Boucher ◽  
A. Hirose ◽  
H. Kuwahara ◽  
A. H. Morton ◽  
H. M. Skarsgard ◽  
...  
Keyword(s):  
Energy Balance ◽  
Thermal Transport ◽  
Ion Heating ◽  
Heating Device ◽  
Turbulent Heating

Efficient electron and ion heating is observed in a toroidal turbulent heating device, STOR-I. Energy balance and preferentially inward thermal transport are confirmed.

Observation of a current-limited double layer in a linear turbulent-heating device

1985 ◽  
Vol 28 (2) ◽  
pp. 703 ◽  
Author(s):  
Hiroshi Inuzuka ◽  
Yutaka Torii ◽  
Masaaki Nagatsu ◽  
Takashige Tsukishima
Keyword(s):  
Double Layer ◽  
Heating Device ◽  
Turbulent Heating ◽  
A Current

Turbulent heating experiment in the STOR-1M tokamak

1989 ◽  
Vol 67 (9) ◽  
pp. 884-892 ◽  
Author(s):  
A. Sarkissian ◽  
A. Hirose ◽  
O. Mitarai ◽  
S. Wolfe ◽  
H. M. Skarsgard
Keyword(s):  
Plasma Confinement ◽  
Ion Heating ◽  
Heating Pulse ◽  
Current Rise ◽  
Heating Phase ◽  
Turbulent Heating ◽  
Rapid Current ◽  
Rise Phase ◽  
Plasma Behavior

In this paper the STOR-1M tokamak and its diagnostics are described. The plasma behavior before, during, and after turbulent heating is also discussed. Anomalously rapid current penetration has been observed during both the ohmic current-rise phase and the turbulent heating phase. The critical streaming parameter for the onset of current driven turbulence has been measured. Efficient electron and ion heating during turbulent heating has been observed. Plasma confinement properties show significant improvement, following the turbulent heating pulse, for a period much longer than the duration of the turbulent heating pulse.

scholarly journals Plasma ion heating by cryogenic pellet injection

2019 ◽  
Vol 85 (1) ◽  
Author(s):  
Pavel Aleynikov ◽  
Boris N. Breizman ◽  
Per Helander ◽  
Yuriy Turkin
Keyword(s):  
Energy Balance ◽  
Thermal Energy ◽  
Heating Power ◽  
Background Plasma ◽  
Substantial Fraction ◽  
Ion Heating ◽  
Magnetically Confined ◽  
Pellet Injection

The injection of cryogenic pellets into a magnetically confined plasma is shown to be accompanied by a considerable transfer of thermal energy from the electrons in the background plasma to the ions. The resulting ion heating can be significant, particularly in plasmas with disparate electron and ion temperatures, and can affect the energy balance of the plasma. In recent Wendelstein 7-X experiments, this mechanism can account for a substantial fraction of the ion heating power during pellet injection.

Simultaneous Ion Heating ofHe+andAr+in Linear Turbulent-Heating Experiments

1972 ◽  
Vol 29 (18) ◽  
pp. 1223-1226 ◽  
Author(s):  
K. Adati ◽  
T. Kawabe ◽  
T. Oda ◽  
Y. Takezaki ◽  
T. Yokota ◽  
...  
Keyword(s):  
Ion Heating ◽  
Turbulent Heating

Direct observation of a strong electron hole in a linear turbulent heating device

1988 ◽  
Vol 37 (4) ◽  
pp. 542-545 ◽  
Author(s):  
Hiroshi Inuzuka ◽  
Akihiro Suzuki ◽  
Masaaki Nagatsu ◽  
Takashige Tsukishima
Keyword(s):  
Direct Observation ◽  
Electron Hole ◽  
Strong Electron ◽  
Heating Device ◽  
Turbulent Heating

scholarly journals Thermal disequilibration of ions and electrons by collisionless plasma turbulence

2018 ◽  
Vol 116 (3) ◽  
pp. 771-776 ◽  
Author(s):  
Yohei Kawazura ◽  
Michael Barnes ◽  
Alexander A. Schekochihin
Keyword(s):  
Magnetic Energy ◽  
Collisionless Plasma ◽  
Nonequilibrium State ◽  
Ion Distribution ◽  
Ion Heating ◽  
Phase Mixing ◽  
Nonlinear Phase ◽  
Turbulent Heating ◽  
Hybrid Fluid ◽  
Increasing Function

Does overall thermal equilibrium exist between ions and electrons in a weakly collisional, magnetized, turbulent plasma? And, if not, how is thermal energy partitioned between ions and electrons? This is a fundamental question in plasma physics, the answer to which is also crucial for predicting the properties of far-distant astronomical objects such as accretion disks around black holes. In the context of disks, this question was posed nearly two decades ago and has since generated a sizeable literature. Here we provide the answer for the case in which energy is injected into the plasma via Alfvénic turbulence: Collisionless turbulent heating typically acts to disequilibrate the ion and electron temperatures. Numerical simulations using a hybrid fluid-gyrokinetic model indicate that the ion–electron heating-rate ratio is an increasing function of the thermal-to-magnetic energy ratio, βi: It ranges from ∼0.05 at βi=0.1 to at least 30 for βi≳10. This energy partition is approximately insensitive to the ion-to-electron temperature ratio Ti/Te. Thus, in the absence of other equilibrating mechanisms, a collisionless plasma system heated via Alfvénic turbulence will tend toward a nonequilibrium state in which one of the species is significantly hotter than the other, i.e., hotter ions at high βi and hotter electrons at low βi. Spectra of electromagnetic fields and the ion distribution function in 5D phase space exhibit an interesting new magnetically dominated regime at high βi and a tendency for the ion heating to be mediated by nonlinear phase mixing (“entropy cascade”) when βi≲1 and by linear phase mixing (Landau damping) when βi≫1.

scholarly journals Mechanisms of spontaneous collapse of double layer in a linear turbulent heating device.

1989 ◽  
Vol 62 (2) ◽  
pp. 138-150
Author(s):  
Hiroshi Inuzuka ◽  
Isamu Akakabe ◽  
Takashige Tsukishima
Keyword(s):  
Double Layer ◽  
Heating Device ◽  
Turbulent Heating

Ion heating and energy balance during magnetic reconnection events in the RFX-mod experiment

2021 ◽  
Author(s):  
Marco Gobbin ◽  
Matteo Agostini ◽  
Fulvio Auriemma ◽  
Lorella Carraro ◽  
Roberto Cavazzana ◽  
...  
Keyword(s):  
Energy Balance ◽  
Magnetic Energy ◽  
High Time Resolution ◽  
High Current ◽  
Ion Heating ◽  
Astrophysical Plasmas ◽  
X Ray ◽  
Balance Analysis ◽  
Reversed Field ◽  
Energy Balance Analysis

Abstract Reconnection events in high current reversed field pinch plasmas are often associated to the partial or total loss of the helical magnetic topology. The electron temperature collapse during these phenomena is investigated in RFX-mod thanks to high time resolution soft-x-ray diagnostics; these data are used, together with magnetic energy reconstructions, for energy balance analysis. The paper shows that the energy released during reconnection events, similarly to astrophysical plasmas, might be involved in ion heating, the latter being estimated by the energy distribution function of neutral atoms, a rather interesting feature in a reactorial perspective. These issues will be further investigated in RFX-mod2, an upgrade of the present device starting its operations from 2022, where the modified boundary conditions are expected to increase the helical states duration and reduce the frequency of reconnection events.

Effects of Ambipolar Diffusion on Prominence Thread Models

1994 ◽  
Vol 144 ◽  
pp. 315-321 ◽  
Author(s):  
M. G. Rovira ◽  
J. M. Fontenla ◽  
J.-C. Vial ◽  
P. Gouttebroze
Keyword(s):  
Energy Balance ◽  
Transition Region ◽  
Ambipolar Diffusion ◽  
Line Profiles ◽  
Balance Equations ◽  
Model Calculations ◽  
Partial Frequency ◽  
Frequency Redistribution ◽  
Partial Frequency Redistribution ◽  
Theoretical Structure

AbstractWe have improved previous model calculations of the prominence-corona transition region including the effect of the ambipolar diffusion in the statistical equilibrium and energy balance equations. We show its influence on the different parameters that characterize the resulting prominence theoretical structure. We take into account the effect of the partial frequency redistribution (PRD) in the line profiles and total intensities calculations.

Influence of Magnetic Fields on Solar Hydrodynamics: Experimental Results

1977 ◽  
Vol 36 ◽  
pp. 143-180 ◽  
Author(s):  
J.O. Stenflo
Keyword(s):  
Solar Activity ◽  
Energy Balance ◽  
Magnetic Fields ◽  
Solar Atmosphere ◽  
General Problem ◽  
Solar Rotation ◽  
Active Regions ◽  
Physical Conditions ◽  
Dynamic Phenomena

It is well-known that solar activity is basically caused by the Interaction of magnetic fields with convection and solar rotation, resulting in a great variety of dynamic phenomena, like flares, surges, sunspots, prominences, etc. Many conferences have been devoted to solar activity, including the role of magnetic fields. Similar attention has not been paid to the role of magnetic fields for the overall dynamics and energy balance of the solar atmosphere, related to the general problem of chromospheric and coronal heating. To penetrate this problem we have to focus our attention more on the physical conditions in the ‘quiet’ regions than on the conspicuous phenomena in active regions.

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