Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Miyato, Naoaki; Kishimoto, Yasuaki; Li, J.*
Journal of Plasma Physics, 72(6), p.821 - 824, 2006/12
Times Cited Count：0 Percentile：0.01(Physics, Fluids & Plasmas)Zonal flow behaviour and its effect on turbulent transport in reversed shear tokamaks are investigated by global nonlinear simulation of ion temperature gradient driven turbulence. When safety factor 
is reduced, zonal flows in a minimum region change from oscillatory ones to stationary ones and suppress the turbulent transport effectively. This result indicates that the change of zonal flow behaviour in the minimum region may trigger the formation of ion transport barriers.
Idomura, Yasuhiro; Tokuda, Shinji; Kishimoto, Yasuaki
Nuclear Fusion, 45(12), p.1571 - 1581, 2005/12
Times Cited Count：39 Percentile：74.86(Physics, Fluids & Plasmas)Using a global gyrokinetic toroidal particle code, the toroidal electron temperature gradient driven (ETG) turbulence is studied in positive and reversed shear tokamaks. In the nolinear turbulent state, the ETG turbulence in the positive and reversed shear configurations show quite different structure formations. In the positive shear configuration, the ETG turbulence is dominated by streamers which have a ballooning type structure, and the electron temperature 
profile is quickly relaxed to the marginally stable state in a turbulent time scale. In the reversed shear configuration, quasi-steady zonal flows are produced in the regative shear region, while the positive shear region is characterized by streamers. Accordingly, the electron thermal diffusivity 
has a gap structure across the 
surface, and the gradinet is sustained above the marginal value for a long time in the quasi-steady phase. The results suggest a stiffness of the profile in positive shear tokamaks, and a possibility of the Te transport barrier in reversed shear tokamaks.
Chankin, A. V.
Physics of Plasmas, 11(4), p.1484 - 1492, 2004/04
Times Cited Count：12 Percentile：37.27(Physics, Fluids & Plasmas)no abstracts in English
; Tasaka, Kanji
JAERI-M 8670, 46 Pages, 1980/02
no abstracts in English
