搜索

x
中国物理学会期刊

HL-2A中环向旋转影响等离子体对共振磁扰动的响应过程

CSTR: 32037.14.aps.69.20200519

Effect of toroidal rotation on plasma response to resonant magnetic perturbations in HL-2A

CSTR: 32037.14.aps.69.20200519
PDF
HTML
导出引用
  • 利用MARS-F代码在HL-2A装置下模拟等离子体对共振磁扰动的线性响应过程, 研究了等离子体旋转频率对响应的影响. 研究发现, 扰动场在有理面上的屏蔽效应在旋转频率较大时随旋转增大而增强, 但在旋转频率较小时电阻导致的屏蔽效果最强处较有理面的偏移会影响这一规律; 扰动场在非有理面上的放大效应主要由芯部扭曲响应引起, 且同时与等离子体旋转频率和电阻密切相关.

     

    Resonant magnetic perturbation (RMP), generated by externally applied magnetic perturbation coils, is an important method of controlling plasma edge localized mode. Many experiments have shown that RMP can effectively mitigate/suppress edge localized mode, but its intrinsic physical mechanism is not completely clear. The response of plasma to RMP is the key to understanding the RMP physics. In the presence of RMP, the circumferential symmetry of the tokamak magnetic field will be broken, forming a new three-dimensional(3D) equilibrium, and this process is called the plasma response to RMP. Currently, the parameter range and control effect of RMPs to control edge localized mode on different devices are quite different, implying that the plasma response to RMPs has different response results in different parameter ranges on different devices. Therefore, it is necessary to study the RMP response characteristics of specific devices.
    In this work, the effect of the plasma rotation frequency on the linear response process of plasma to the resonant magnetic perturbations is investigated in the framework of MARS-F in the HL-2A configuration, and the physical reasons are analyzed in detail. It is found that the shielding and amplification effects in plasma response do not change linearly with plasma rotation frequency, since the plasma resistivity plays an important role. The shielding effect for the magnetic perturbation on the rational surface is enhanced with the increase of the rotation frequency in the high rotation frequency range. However, this rule no longer holds true in the low rotation frequency range due to the deviation of the strongest shielding position from the rational surface caused by the plasma resistivity. As for the amplification effect, the resistivity weakens the amplification effect of plasma response due to the dissipation of induced current. The variation trend of the amplification effect with the rotation frequency and resistivity is consistent with that of the core-kink response, which indicates that the amplification effect of the magnetic perturbation is mainly caused by the core-kink response.

     

    目录

    /

    返回文章
    返回