Drift Waves and Vortices in Shear Magnetized Plasma with Low Beta and Finite Ions Temperature Gradient

Abstract

The derivation of reduced nonlinear fluid equations for the description of drift wave turbulence and vortices in low beta confinement, systems with magnetic shear is considered, where the effects associated with trapped particles could be neglected. In the present work, a set of reduced equations governing the slab-type ion temperature gradient driven mode in a shear magnetized plasma with low frequency, is derived which is generalization of the two fluid equations. With the use the model, equations are derived for the drift instabilities from the electrostatic two-fluid equations. The electrical resistivity included in the system that allows the dynamics of both the collisionless ion temperature gradient driven instability and the collisional drift wave instability of plasma. The model equations was used extensively in earlier nonlinear studies and the research developed it as appropriate limits of the model equations derived in the present work, where the effects of sheared velocity flows in the equilibrium plasma. The compressible two fluid equations are considered when fluctuation of magnetic field and electron temperature are ignored. It is also assumed that the mode is localized on a particular magnetic field line, typical frequency and growth rate of the model, which are much smaller than the ion cyclotron frequency. The dispersion relation of the slab-type ion temperature gradient driven mode is obtained for both collisionless and collisional drift waves in sheared magnetic fields of plasma. This illustrates that the strong magnetic shear has a stabilizing effect on the collisionless ion temperature gradient drift instability, which is not shown in collisional drift instability.