Theory of Fine-scale Zonal Flow Generation From Trapped Electron Mode Turbulence

Hahm, Lu Wang and T.S.

Princeton University. Plasma Physics Laboratory.

关键词: Shielding;    70 Plasma Physics And Fusion Technology;    Kinetics;    Trapped Electrons;    Polarization;   

DOI  :  10.2172/958407
RP-ID  :  PPPL-4414
RP-ID  :  DE-AC02-09CH11466
RP-ID  :  958407

美国|英语

来源: UNT Digital Library

【 摘 要 】

Most existing zonal flow generation theory has been developed with a usual assumption of qrρθ¡ << 1 (qr is the radial wave number of zonal flow, and ρθ¡ is the ion poloidal gyrora- dius). However, recent nonlinear gyrokinetic simulations of trapped electron mode (TEM) turbulence exhibit a relatively short radial scale of the zonal flows with qrρθ¡ ~ 1 [Z. Lin et al., IAEA-CN/TH/P2-8 (2006); D. Ernst et al., Phys. Plasmas 16, 055906 (2009)]. This work reports an extension of zonal flow growth calculation to this short wavelength regime via the wave kinetics approach. A generalized expression for the polarization shielding for arbitrary radial wavelength [Lu Wang and T.S. Hahm, to appear in Phys. Plasmas (2009)] which extends the Rosenbluth-Hinton formula in the long wavelength limit is applied.