HL-1装置低杂波电流驱动波导阵列优化设计

OPTIMAZING DESIGN OF LHCD GRILL IN THE HL-1 TOKAMAK

本文利用Brambilla的波导阵列理论,结合HL-1装置的具体参数,计算了2.45 GHz低杂波耦合系统的波谱及波能的总体反射系数与边界等离子体密度剖面的关系。结果表明,要得到好的耦合效率及适合于电流驱动实验的波谱,有必要使波导口伸入孔栏阴影区1—1.5cm,使之尽量突破截止层,同时调节各波导间的相位差在70°—100°之间。

Considering the specific parameters of HL-1 tokamak, a code for calculating the Brambilla's grill is developed. This code is used to obtain the wave power spectrum and its overall reflection coefficient from the plasma edge for a 2.45GHz lower hybrid wave with different density profiles assumed. It is shown that to obtain a good coupling it is necessary to put the grill mouth into the shadow region of the limiter with a depth of about 1cm to 1.5cm and make it break through the cut-off layer as far as possible. On the other hand, by adjusting the grill phase difference in the range of 70° to 100°,it is possible to get a satisfactory wave power spectrum.