Simulations of nonlinear interaction between beta-induced Alfvén eigenmode and tearing mode

Nuclear Fushion

article

Sizhe Duan¹  Xiaogang Wang²  Huishan Cai¹  Ding Li³ 

[1] School of Nuclear Science and Technology, University of Science and Technology of China;Department of Physics, Harbin Institute of Technology;Institute of Physics, Chinese Academy of Sciences;Songshan Lake Materials Laboratory;University of Chinese Academy of Sciences

关键词: beta-induced Alfvén eigenmode;    tearing mode;    wave-particle interaction;    mode coupling;    energetic particles;   

DOI  :  10.1088/1741-4326/acb802

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

The nonlinear interaction between the m/n = 2/1beta-induced Alfvén eigenmode (BAE) and the m/n = 2/1tearing mode (TM) observed in the HL-2A experiment is systematically studied with the hybrid kinetic-magnetohydrodynamic code M3D-K. It is found that the nonlinear growth of TM can lead to a gradient buildup on the magnetic island (MI) edge, and then triggers the destabilization of the linearly-stable BAE. Then, the triggered BAE together with TM can produce a significant redistribution of energetic particles. For BAE linearly-dominant-unstable case, the TM activity results in the inward motion of BAE mode structure, and the BAE can have a delay effect on the MI saturation. Furthermore, a high-frequency axisymmetric m/n = 0/0'breathing' mode is generated by the mode coupling of BAE and TM, agreeing well with the experimental observation, and causes the synchronized periodic oscillation of MI width.

【 授权许可】

Unknown