Nonlinear dynamics and anomalous energy transport in an electrostatic ion-temperature-gradient driven drift-dissipative mode

By using Braginskii transport equations for ions and Boltzmann distribution for electrons, a new system of nonlinear equations governing the dynamics of low-frequency, short-wavelength electrostatic waves in the presence of e quilibrium density, temperature, magnetic field, and electrostatic potentia l gradients has been derived. New ion-temperature-gradient (ITG) driven dri ft-dissipative modes are shown to exist. An expression for anomalous ion en ergy transport caused by nonthermal electrostatic fluctuations is also deri ved. Furthermore, possible stationary solutions of the nonlinear system are obtained in the form of double vortex. On the other hand, the temporal beh avior of newly derived nonlinear dissipative systems can be described by th e generalized Lorenz-Stenflo equations which admit chaotic solutions. The r esults of the present investigation should be helpful for understanding the wave phenomena in space and tokamak plasmas. (C) 1999 American Institute o f Physics. [S1070-664X(99)04308-6].