氦气压强对单脉冲过程电光开关特性影响的数值分析

根据单脉冲过程电光开关气体放电的微观物理过程,提出了氦气放电的一维数值模型。用数值方法分析了气压对单脉冲过程电光开关的气体击穿、放电电流、KDP晶体两侧电压、开关效率、开关速度、等离子区电子温度及等离子体浓度的影响。数值计算结果表明,气压主要影响开关速度的快慢,而对开关效率的大小影响作用不大。在相同开关脉冲的驱动下,在气压较低的情况下,开关速度随气压增大而变快;而在气压较高的情况下,开关速度随气压增大而变慢。由此得到口径为8cm×8cm电光开关的最佳工作气压为1-4 kPa的结论。

Numerical Analysis of Helium-Pressure Influence on Characteristics of Electro-Optic Switch Driven by Single-Pulse Process

A one-dimensional numerical model for analyzing helium discharging of electro-optic switch driven by single-pulse process is proposed based on its microscopic physical mechanism. The influences of operating pressure on the characteristics of electro-optic switch driven by single-pulse process, such as gaseous breakdown, discharging current, charging voltage on KDP crystal, switching efficiency, switching speed, electron temperature, plasma density are numerically analyzed. Calculated results demonstrate that switching speed is obviously influenced by operating pressure, and operating pressure influences switching efficiency weakly. Under the same driven pulse, switching speed becomes quicker when operating pressure is enhanced in the case of low operating pressure, and it will be slower when the pressure is enhanced in the case of high operating pressure. It can be proved from results that optimum operating pressure is between 1000 Pa and 4000 Pa for electro-optic switch with an aperture of 8 cm×8 cm.