Multiple broadband Alfvenic chirping modes(CMs),with frequencies in the wide range of f-35-150 kHz and chirping down rapidly,are found in HL-2A neutral beam injection plasmas,and the CMs can even coexist.The frequency...Multiple broadband Alfvenic chirping modes(CMs),with frequencies in the wide range of f-35-150 kHz and chirping down rapidly,are found in HL-2A neutral beam injection plasmas,and the CMs can even coexist.The frequency chirping down process can be completed within-1 ms,and the frequency shift can reach 30-50 kHz.The CMs propagate in ion diamagnetic drift directions poloidally.The toroidal mode number is confirmed to be n=1,2,3 and 4 for the f-35-65,55-90,70-120 and 100-150 kHz CMs,respectively.The CMs are more like to be energetic-particle continuum modes(EPMs),since the modes almost locate on the Alfven continuum.展开更多
This paper describes the fishbone mode phenomena during the injection of highpower neutral beams in EAST（Experimental Advanced Superconducting Tokamak）.The features of the fishbone mode are presented.The change in f...This paper describes the fishbone mode phenomena during the injection of highpower neutral beams in EAST（Experimental Advanced Superconducting Tokamak）.The features of the fishbone mode are presented.The change in frequency of the mode during a fishbone burst is from 1 kHz to 6 kHz.The nonlinear behavior of the fishbone mode is analyzed by using a prey-predator model,which is consistent with the experimental results.This model indicates that the periodic oscillations of the fishbone mode always occur near the critical value of fast ion beta.Furthermore,the neutral beam analysis for the discharge is done by using the NUBEAM module of the TRANSP code.According to the numerical simulation results and theoretical calculation,it can be concluded that the fishbone mode is driven by the deeply trapped energetic beam ions in EAST.展开更多
基金Supported by the National Key R&D Program of China (Grant Nos.2018YFE0304102,2019YFE03020000 and 2017YFE0301202)the National Natural Science Foundation of China (Grant Nos.11875024,11875021,11835010 and 12005054)the Sichuan Provincial Science and Technology Project (Grant Nos.2020YFSY0047 and 2020JDJQ0070)。
文摘Multiple broadband Alfvenic chirping modes(CMs),with frequencies in the wide range of f-35-150 kHz and chirping down rapidly,are found in HL-2A neutral beam injection plasmas,and the CMs can even coexist.The frequency chirping down process can be completed within-1 ms,and the frequency shift can reach 30-50 kHz.The CMs propagate in ion diamagnetic drift directions poloidally.The toroidal mode number is confirmed to be n=1,2,3 and 4 for the f-35-65,55-90,70-120 and 100-150 kHz CMs,respectively.The CMs are more like to be energetic-particle continuum modes(EPMs),since the modes almost locate on the Alfven continuum.
基金supported by the National Magnetic Confinement Fusion Science Program of China(Nos.2013GB101001,2014DFG61950 and2013GB112003)National Natural Science Foundation of China(Nos.11175211 and 11275233)
文摘This paper describes the fishbone mode phenomena during the injection of highpower neutral beams in EAST（Experimental Advanced Superconducting Tokamak）.The features of the fishbone mode are presented.The change in frequency of the mode during a fishbone burst is from 1 kHz to 6 kHz.The nonlinear behavior of the fishbone mode is analyzed by using a prey-predator model,which is consistent with the experimental results.This model indicates that the periodic oscillations of the fishbone mode always occur near the critical value of fast ion beta.Furthermore,the neutral beam analysis for the discharge is done by using the NUBEAM module of the TRANSP code.According to the numerical simulation results and theoretical calculation,it can be concluded that the fishbone mode is driven by the deeply trapped energetic beam ions in EAST.
