Numerical calculation of plasma response to RMP for HL-2M tokamak

doi:10.16568/j.0254-6086.202201011

Abstract

Abstract: Using the toroidal single-fluid code MARS-F, the plasma response to the phase difference of the resonance magnetic perturbation (RMP) field coil currents is studied in HL-2M equilibrium configuration (I_p=1.0MA, β_N=1.62, q₉₅=4.01). At the optimal phase difference, the perturbing magnetic field significantly changes the topology of the magnetic field in the boundary layer, forms obvious magnetic island chains, increases the transport of plasma in the layer, and reduces the pressure gradient and the drive to the ELM. The optimal phase differences are about 180°, 150° and -30° for the n=1, 2 and 4 toroidal modulus of the disturbance fields, , respectively.

Key words: HL-2M tokamak, Resonance magnetic perturbation, Plasma response

摘要： 在HL-2M托卡马克平衡位形(Ip=1.0MA，β_N=1.62，q₉₅=4.01)下，使用环形单流体程序MARS-F研究了等离子体对共振磁扰动(RMP)线圈电流相位差的响应。在最优相位差时，扰动磁场显著地改变边界层磁场的拓扑，形成明显的磁岛链，增加了等离子体在边界层的输运，降低了压强梯度，减小了对ELM的驱动。模拟结果显示，扰动场环向模数为n=1时，最优的相位差约为180°；n=2时，最优的相位差约为150°；n=4时，最优的相位差约-30°。

关键词: HL-2M托卡马克, 外加扰动磁场, 等离子体共振响应

CLC Number:

TL62⁺2

CHEN Hai-tao, HAO Guang-zhou, LIU Yue-qiang, ZHOU Li-na, CHEN Qian, DUAN Xu-ru. Numerical calculation of plasma response to RMP for HL-2M tokamak[J]. Nuclear Fusion and Plasma Physics, 2022, 42(1): 63-70.

陈海涛, 郝广周, 刘钺强, 周利娜, 陈谦, 段旭如. HL-2M等离子体对共振磁扰动线圈电流相位响应的模拟[J]. 核聚变与等离子体物理, 2022, 42(1): 63-70.

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