Effects of ion polarization and finite-β on heat transport in slab electron-temperature-gradient driven turbulence

2021 ◽  
Vol 28 (5) ◽  
pp. 052512
Author(s):  
S. Maeyama ◽  
S. Kusaka ◽  
T.-H. Watanabe
Keyword(s):  
Temperature Gradient ◽  
Electron Temperature ◽  
Heat Transport ◽  
Electron Temperature Gradient

scholarly journals Investigation of the role of electron temperature gradient modes in electron heat transport in TCV plasmas

2019 ◽  
Vol 59 (12) ◽  
pp. 126017 ◽  
Author(s):  
A. Mariani ◽  
P. Mantica ◽  
S. Brunner ◽  
M. Fontana ◽  
A. Karpushov ◽  
...  
Keyword(s):  
Temperature Gradient ◽  
Electron Temperature ◽  
Heat Transport ◽  
Electron Temperature Gradient ◽  
Electron Heat

Comparison between fluid electron-temperature-gradient driven simulations and Tore Supra experiments on electron heat transport

2007 ◽  
Vol 73 (2) ◽  
pp. 199-206
Author(s):  
B. LABIT ◽  
M. OTTAVIANI
Keyword(s):  
Thermal Conductivity ◽  
Temperature Gradient ◽  
Electron Temperature ◽  
Heat Transport ◽  
Three Dimensional ◽  
High Electron ◽  
Present Contribution ◽  
Electron Thermal Conductivity ◽  
Electron Temperature Gradient ◽  
Electron Heat

Abstract.In recent years, much attention has been devoted to the electron-temperature-gradient (ETG) driven instability as a possible explanation for the high electron thermal conductivity found in most tokamaks. The present contribution assesses whether a specific three-dimensional fluid ETG model can reproduce the conductivity observed in the Tore Supra tokamak [Equipe Tore Supra (presented by R. Aymar) 1989 Plasma Physics and Controlled Nuclear Fusion Research (Proc. 12th Int. Conf., Nice, 1988, Vol. 1.) Vienna: IAEA, p. 9]. Although the model reproduces fairly well the observed critical gradient, a large discrepancy factor, of the order of 50, is found for the ratio between the experimental and the simulated conductivity. On the basis of this study, one must conclude that the electron heat transport cannot be explained only with a fluid ETG turbulence model.

Ion scale nonlinear interaction triggered by disparate scale electron temperature gradient mode

2015 ◽  
Vol 22 (5) ◽  
pp. 052301
Author(s):  
Chanho Moon ◽  
Tatsuya Kobayashi ◽  
Kimitaka Itoh ◽  
Rikizo Hatakeyama ◽  
Toshiro Kaneko
Keyword(s):  
Temperature Gradient ◽  
Electron Temperature ◽  
Nonlinear Interaction ◽  
Electron Temperature Gradient ◽  
Gradient Mode

scholarly journals Excitation of zonal flow by the modulational instability in electron temperature gradient driven turbulence

2008 ◽  
Vol 74 (3) ◽  
pp. 381-389 ◽  
Author(s):  
Yu. A. ZALIZNYAK ◽  
A. I. YAKIMENKO ◽  
V. M. LASHKIN
Keyword(s):  
Temperature Gradient ◽  
Electron Temperature ◽  
Large Scale ◽  
Modulational Instability ◽  
Zonal Flow ◽  
Finite Amplitude ◽  
Small Scale ◽  
Drift Waves ◽  
Zonal Flows ◽  
Electron Temperature Gradient

AbstractThe generation of large-scale zonal flows by small-scale electrostatic drift waves in electron temperature gradient driven turbulence model is considered. The generation mechanism is based on the modulational instability of a finite amplitude monochromatic drift wave. The threshold and growth rate of the instability as well as the optimal spatial scale of zonal flow are obtained.

Comparison of dynamical features between the fast H-L and the H-I-L transition for EAST RF-heated plasmas

2021 ◽  
Author(s):  
Liang Chen ◽  
Guo Sheng Xu ◽  
Linming Shao ◽  
Wei Gao ◽  
Yifeng Wang ◽  
...  
Keyword(s):  
Temperature Gradient ◽  
Electron Temperature ◽  
Intermediate Phase ◽  
Critical Role ◽  
Potential Gradient ◽  
Flow Shear ◽  
Important Distinction ◽  
Radial Gradient ◽  
Electron Temperature Gradient ◽  
Dynamical Features

Abstract In this paper, a comparison of dynamical features between the fast H-L and the H-I-L transition, which can be identified by the intermediate phase, or ‘I-phase’, has been made for radio-frequency (RF) heated deuterium plasmas in EAST. The fast H-L transition is characterized by a rapid release of stored energy during the transition transient, while the H-I-L transition exhibits a ‘soft’ H-mode termination. One important distinction between the transitions has been observed by dedicated probe measurements slightly inside the separatrix, with respect to the radial gradient of the floating potential, which corresponds to the E×B flow and/or the electron temperature gradient. The potential gradient inside the separatrix oscillates and persists during the stationary I-phase, and shows a larger amplitude than that before the fast H-L transition. The reduction of the gradient leads to the final transition to the L-mode for both the fast H-L and the H-I-L transition. These findings indicate that the mean E×B flow shear and/or edge electron temperature gradient play a critical role underlying the H-L transition physics. In addition, the back transition in EAST is found to be sensitive to magnetic configuration, where the vertical configuration, i.e., inner strike-point located at vertical target, favours access to the H-I-L transition, while the horizontal shape facilitates achievement of the fast H-L transition. The divertor recycling level normalized to electron density is higher before the fast H-L transition, as compared to that before the I-phase, which strongly suggest that the density of the recycled neutrals is an important ingredient in determining the back transition behaviour.

Sign in / Sign up

Export Citation Format

Share Document