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arXiv · 2101.01924

Role of wave-particle resonance in turbulent transport in toroidal plasmas

Ge Dong·Zhihong Lin
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Abstract

Wave-particle interaction in toroidal plasmas is an essential transport mechanism in drift wave instability-driven microturbulence. In tokamkas, different wave-particle resonance conditions have been found important for the energy and particle transport of multiple species in various drift wave turbulences. To confirm the transport mechanism for electrons and ions in tokamak drift-wave instabilities, the effect of wave-particle resonance on turbulent transport is studied using global gyrokinetic particle simulations of the plasma core ion temperature gradient (ITG) and collisionless trapped electron mode (CTEM) turbulence. Simulation results show that in CTEM and ITG turbulence, electron transport is primarily regulated by wave-particle linear resonance, and the ion transport is regulated by nonlinear wave-particle decorrelation.

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Ge Dong, Zhihong Lin. 2021-01-06. Role of wave-particle resonance in turbulent transport in toroidal plasmas. https://doi.org/10.1088/1361-6587/ac4275

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