Electrostatic stability theory of tokamaks from two-component fluid equations

Abstract

The electrostatic stability theory of tokamak plasmas is developed from the two-component fluid equations. The consistent treatment of the collisional equations with the transport processes from Coulomb scattering shows the relative importance of the transport processes of resistivity, viscosity, the thermoelectric effect, and thermal conduction in the several plasma modes. The plasma modes derived from the electrostatic equations are the sound waves, the drift wave, and thermal modes. The growth rates are given as functions of the driving forces of the tokamak current, the density gradient, and the temperature gradients. At finite aspect ratio, the equations describing the current driven drift-sound waves are solved for the toroidal shift in the growth rate. In addition to the gradient-B drifts previously modeled by a periodic gravity, it is shown that consistency requires inclusion of the plasma compression due to the modulation of the parallel and perpendicular fluxes in the nonuniform magnetic field.