Velocity - Ion Temperature Gradient Driven Modes and Angular Momentum Transport in Magnetically

نویسندگان

  • John Chandler Thomas
  • John Chandler
  • Chris Crabtree
  • Kevin Takasaki
چکیده

Plasma confinement experiments continue to uncover fascinating phenomena that motivate theoretical discussion and exploration. In this thesis, we consider the phenomenon of angular momentum transport in magnetically confined plasmas. Relevant experiments and theoretical developments are presented in order to motivate the derivation of a modified version of the three-field nonlinear Hamaguchi-Horton equations[1]. The equations are altered to include a zeroth-order parallel velocity inhomogeneity along the radially-analagous coordinate, resulting in a nonlinear system that describes the evolution of the velocity-ion temperature gradient-driven modes (VITGs). The equations are used to analyze VITG modes in the local approximation of a magnetized plasma, as well as in an inhomogeneous slab model. Applying quasilinear methods, we find a turbulent angular momentum flux in agreement with the accretion theory of the spontaneous rotation phenomenon[2]. More advanced applications are considered for future analysis. Thesis Supervisor: Bruno Coppi Title: Professor of Physics

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تاریخ انتشار 2008