Turbulent Particle Transport in Magnetized Plasmas

TLDR

Particle transport in magnetized plasmas is investigated using a fluid model of drift wave turbulence. The study employs a fluid model of drift wave turbulence to analyze particle transport. Analytical and numerical results show that magnetic field curvature and thermodiffusion drive an anomalous inward pinch, with curvature dominating for equal ion and electron heat sources and thermodiffusion reversing direction as the electron‑to‑ion pressure gradient ratio increases, consistent with turbulence equipartition theory.

Abstract

Particle transport in magnetized plasmas is investigated with a fluid model of drift wave turbulence. An analytical calculation shows that magnetic field curvature and thermodiffusion drive an anomalous pinch. The curvature driven pinch velocity is consistent with the prediction of turbulence equipartition theory. The thermodiffusion flux is found to be directed inward for a small ratio of electron to ion pressure gradient, and it reverses its sign when increasing this ratio. Numerical simulations confirm that a turbulent particle pinch exists. It is mainly driven by curvature for equal ion and electron heat sources. The sign and relative weights of the curvature and thermodiffusion pinches are consistent with the analytical calculation.