Statistical theory of resistive drift-wave turbulence and transport
In this paper resistive drift-wave turbulence in a slab geometry is studied by statistical closure methods and direct numerical simulations. The two-field Hasegawa-Wakatani (HW) fluid model is a paradigm for understanding the generic nonlinear behavior of multiple-field plasma turbulence, A gyrokinetic derivation of the HW model is sketched. The recently developed Realizable Markovian Closure (RMC) is applied to the HW model; spectral properties, nonlinear energy transfers, and turbulent transport calculations are discussed. The closure results are also compared to direct numerical simulation results; excellent agreement is found. The transport scaling with the adiabaticity parameter, which measure the strength of the parallel electron resistivity, in analytically derived and understood through weak-turbulence and strong-turbulence analyses. No evidence is found to support previous suggestions that coherent structures cause a large depression of saturated transport from its quasilinear value in the hydrodynamic regime of the HW model. Instead, the depression of transport is well explained by the spectral balance equation of the (second-order) statistical closure when account is taken of incoherent noise.
Bibliographic Reference: Article: Physics of Plasmas, Vol. 4 (1997) No. 6, pp. 2116-2133
Record Number: 199710962 / Last updated on: 1997-08-14
Original language: en
Available languages: en