Anomalous transport of multi-species edge plasma with the generalized Hasegawa–Wakatani model and the FLR effects

Abstract

Anomalous transport of multi-species plasma is considered with the generalized Hasegawa–Wakatani model [A. R. Knyazev and S. I. Krasheninnikov, Phys. Plasmas 31, 012502 (2024)] further extended to incorporate the Finite Larmor Radius (FLR) effects. By introducing the “associated” enstrophy, it is shown that with no FLR effects (where anomalous transport of all ion species is described as a transport of passive scalars in the turbulent fields of the electrostatic potential and electron density fluctuations) the fluctuating densities of ion species converge to the state where they are linearly proportional to electron density and vorticity fluctuations, which confirm previous numerical findings of [A. R. Knyazev and S. I. Krasheninnikov, Phys. Plasmas 31, 012502 (2024)]. However, in contrast to the “cold” ion approximation, with the FLR effects included, both the plasma turbulence and the dynamics of all ion species become interconnected. Therefore, for simplicity, the FLR effects in this work were considered only for a small “trace” impurity fraction. It is found that for light (neon) “trace” impurity, the FLR effects reduce both anomalous flux and density fluctuations. However, for heavy (tungsten) “trace” impurity, the FLR effects exhibit non-monotonic impact on anomalous transport.