在Hall MHD方程组中引入外部驱动电流项,数值模拟外部驱动电流对双撕裂模不稳定性的影响。结果表明,在x点加入反向外部驱动电流对撕裂模的发展有抑制作用,周期性的外部驱动电流对双撕裂模不稳定性的抑制效果较好,能控制磁岛的尺度在相互驱动的临界尺度以下,避免发生双撕裂模非线性磁场重联的爆发,随着驱动电流周期变大抑制效果变坏,在一定限度内随着驱动电流强度增大抑制效果变好,在一定范围内随着驱动电流宽度变小抑制效果变好。
Effects of external current drive on instability of double tearing mode in Hall MHD equations are numerically investigated. It shows that double tearing mode can be suppressed by antiparallel external current drive at xpoint of tearing mode magnetic islands. Periodic external current drive controls island width under a threshold and stabilizes double tearing mode. With increasing period depression effect becomes worse. If frequency, density and width of periodic external current drive are adopted suitably, depression effect becomes better.