两间隙毛细管等离子体发生器触发放电数值模拟  

Theoretical Studies on Trigger Discharges in a Two-gap Capillary Plasma Generator

作　　者：夏胜国[1] 何俊佳[1] 刘克富[1] 

机构地区：[1]华中科技大学电气与电子工程学院,湖北省武汉市430074

出　　处：《中国电机工程学报》2008年第28期31-35,共5页Proceedings of the CSEE

摘　　要：两间隙毛细管等离子体发生器利用触发间隙放电产生等离子体射流连通主放电间隙,引发主放电形成高温等离子体射流。建立一个一维流体模型对两间隙毛细管触发放电进行模拟,对考虑管壁烧蚀和不考虑管壁烧蚀条件下的触发放电的特性进行计算,分析触发放电过程对主间隙击穿的影响。由于管壁烧蚀补充毛细管内由于开口端流出的质量损失,因此在放电期间毛细管内的气体压强、流速和温度基本保持稳定状态;管壁烧蚀降低了放电时毛细管内的气体温度,但加快了高温区向毛细管开口端的传播速度,因而缩短了主间隙的击穿时延。Energetic plasma jets can be generated using a two-gap capillary plasma generator in which a high energy discharge in main gap is initiated by a small energy discharge within trigger gap. A theoretical model is proposed to investigate the trigger discharge process of this kind of generator. Both ablation case and no ablation case are considered. The calculation shows that capillary wall ablation can greatly change the trigger discharge arc dynamics. In ablation case, the pressure, velocity and temperature of plasma in capillary are in a relative steady-state during the trigger discharge, while these parameters drastically decrease after a short-time rise at the beginning of the trigger discharge in the no ablation case. Wall ablation leads to a lower temperature of the discharge arc. However, the propagation velocity of the high temperature zone in capillary is increased by wall ablation, resulting in a shortened breakdown delay time of the main gap.

关 键 词：毛细管放电 等离子体射流 管壁烧蚀 

分 类 号：TM915[电气工程—电力电子与电力传动] TM836