Effects of E×B velocity shear and magnetic shear on turbulence and transport in magnetic confinement devices

Abstract

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On resistive magnetohydrodynamic equilibria of an axisymmetric toroidal plasma with flow

“…Since, according to experimental evidence in tokamaks [29], the (maximum) value of the ion poloidal velocity in the edge region during the L-H transition is of the order of 10 Km/sec and the ion temperature is of the order of 1 KeV, the scaling v p ≪ v s is satisfied in this region. Therefore, the restriction M 2 < 1 is of nonoperational relevance.…”

“…It is noted here that the requirement M 2 < 1 in transformation (29) implies that v 2 p < v 2 s , where v s = (γP/ρ) 1/2 is the sound speed. This follows from Eqs.…”

Formation of Electron-Root Radial Electric Field and its Effect on Thermal Transport in LHD High <i>T</i>_ePlasma

“…The effect of the E × B velocity shear on the growth of the turbulence plays a significant role for the transport reduction, see a review paper by Burrell [17] and references therein. Also it has been shown experimentally that the suppression of the turbulence-driven transport by the E × B velocity shear results in the transport barrier in helical devices [18].…”

Improved CCD Detectors for High Speed, Charge Exchange Spectroscopy Studies on the DIII-D Tokamak

“…Charge exchange spectroscopy has been one of the workhorse diagnostics on the Doublet III and DIII-D tokamaks since 1983 [2]. The ability to determine E r , for example, has been essential in testing the model of E× B shear suppression of turbulence [3], which has revolutionized our understanding of turbulence in magnetized plasmas.…”