3-DIMENSIONAL NUMERICAL SIMULATIONS OF SIMPLE ELECTRON-DRIFT WAVE TURBULENCE IN A SHEARED AND CURVED MAGNETIC-FIELD

A three-dimensional code is used to study the scaling of an electrostatic electron drift wave turbulence with respect to shear and curvature of the magnetic field as well as the driving strength. The electrons are modeled with a simple formula for the deviation from a near Boltzmann response and the ions are modeled as a nonlinear fluid. For sheared slab geometry suppressing curvature (or toroidal) effects, the turbulence level and transport scale according to the mixing length rules with the mixing length given by the linear normal mode widths and the poloidal wavelengths scaled to the ion gyroradius. Toroidal coupling results in a more complex behavior. Some evidence for nonlocal or convective turbulence effects is found. © 1990 American Institute of Physics.