DRIFT-WAVE TURBULENCE IN A PLASMA WITH SHEARED FLOW

A single-equation model of long-wavelength drift waves has been used t o study the behavior of turbulent plasma fluctuations in the presence of sheared flow. These waves, which have a real frequency, are calcula ted using a time-evolution algorithm that includes flow effects. Linea r tests show that growth rates and flow-shear damping agree with the p redictions of analytical theory, even in the presence of a large real frequency. Criteria for selecting the proper spatial and temporal reso lution for nonlinear calculations are described. Convergence tests sho w that, within these limits, solutions have a weak dependence on varia tions of thess resolution parameters. Tests of energy conservation ind icate that calculated solutions remain accurate for large numbers of t ime steps. (C) 1994 Academic Press, Inc.