NONLINEAR DRIFT-WAVE STRUCTURES AND THEIR INFLUENCE ON PARTICLE-TRANSPORT

The nonlinear dynamics of drift-wave turbulence and the resulting tran sport properties are considered in two-dimensional situations. Here dr ift waves are driven unstable via either the universal instability or the drift dissipative instability. Numerical simulations demonstrate t hat drift-wave turbulence contains monopolar, spatially coherent struc tures. The latter are identified by some standard methods. It is shown that coherent structures can account for convective particle transpor t in addition to the fluctuation-induced transport. An approximate lin ear scaling between fluctuation-induced transport and driving strength is found. Estimates for the convective particle transport are present ed.