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arXiv · 1905.07250

High frequency mode generation by toroidal Alfven eigenmodes

Shizhao Wei·Peiwan Shi·Liming Yu·Wei Chen·Ningfei Chen·Zhiyong Qiu
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Abstract

Nonlinear generation of high frequency mode (HFM) by toroidal Alfven eigenmode (TAE) observed in HL-2A tokamak is analyzed using nonlinear gyrokinetic theory. It is found that, the HFM can be dominated by $|nq-m|=1$ perturbations with predominantly ideal magnetohydrodynamic if the two primary TAEs are co-propagating; while the HFM can be characterized by $nq-m=0$ electrostatic perturbations if the two primary TAEs are counter-propagating. Here, $n$ and $m$ are respectively the toroidal and poloidal mode numbers, and $q$ is the safety factor. The nonlinear process is sensitive to the equilibrium magnetic geometry of the device.

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Shizhao Wei, Peiwan Shi, Liming Yu, Wei Chen, Ningfei Chen, Zhiyong Qiu. 2019-05-17. High frequency mode generation by toroidal Alfven eigenmodes. https://doi.org/10.1063/1.5100597

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