Skip to main content
eScholarship
Open Access Publications from the University of California

A novel mechanism for exciting intrinsic toroidal rotation

  • Author(s): McDevitt, CJ
  • Diamond, PH
  • Gürcan, OD
  • Hahm, TS
  • et al.

Published Web Location

https://doi.org/10.1063/1.3122048Creative Commons 'BY-NC-ND' version 4.0 license
Abstract

Beginning from a phase space conserving gyrokinetic formulation, a systematic derivation of parallel momentum conservation uncovers two physically distinct mechanisms by which microturbulence may drive intrinsic rotation. The first mechanism, which emanates from E×B convection of parallel momentum, has already been analyzed [O. D. Gurcan, Phys. Plasmas 14, 042306 (2007); R. R. Dominguez and G. M. Staebler, Phys. Fluids B 5, 3876 (1993)] and was shown to follow from radial electric field shear induced symmetry breaking of the spectrally averaged parallel wave number. Thus, this mechanism is most likely active in regions with steep pressure gradients or strong poloidal flow shear. The second mechanism uncovered, which appears in the gyrokinetic formulation through the parallel nonlinearity, emerges due to charge separation induced by the polarization drift. This novel means of driving intrinsic rotation, while nominally higher order in an expansion of the mode frequency divided by the ion cyclotron frequency, does not depend on radial electric field shear. Thus, while the magnitude of the former mechanism is strongly reduced in regions of weak radial electric field shear, this mechanism remains unabated and is thus likely relevant in complementary regimes. © 2009 American Institute of Physics.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Main Content
Current View