不同气压下介质表面高功率微波击穿的数值模拟

介绍了用于模拟介质表面高功率微波击穿的粒子模拟-蒙特卡罗碰撞方法,并采用该方法模拟研究了氩气环境不同气压下的介质表面高功率微波击穿过程,获得了该击穿过程中粒子数量和电子平均能量的时间变化图像,并得到了击穿延迟时间。数值模拟结果发现:在低气压下,次级电子倍增的作用比较明显,但电子数量在次级电子倍增饱和后的增速较低,击穿延迟时间较长;随着气压的升高,次级电子倍增的影响逐渐变小,气体电离逐渐占主导地位,击穿延迟时间逐渐变短;在高气压下,由于介质表面吸收沉积电子而呈负电性,次级电子倍增消失,击穿延迟时间由气体碰撞电离来决定。

Numerical simulation of high power microwave breakdown on dielectric surface at different gas pressures

This paper presents the electrostatic particle-in-cell (PIC) Monte Carlo collisions (MCC) method for simulating the breakdown on dielectric surface illuminated by high-power microwaves, and the dielectric surface breakdown at different pressures in argon is simulated by the PIC-MCC code. The temporal evolution of the number of particles and the mean kinetic energy of electrons, and the breakdown delay time are obtained. The simulation results show that, in the case of low pressure, the influence of multipactor is visible, while the number of electrons increases slowly after saturation and the breakdown delay is long. As the pressure increases, the influence of multipactor becomes smaller with gas ionization starting to dominate the breakdown process, and the breakdown delay gradually becom