等离子体电磁加速器中快速电磁阀气体注入特性研究

在注气持续时间短、注入气体质量大的快速电磁阀测量中,采用高频响应压力传感器在电磁阀出口测量了气体的动态压力,通过真空室注气前后的压强差测量了注入气体的质量。研究表明,驱动电流、位移限定以及背景气压对气体注入特性有显著影响。当阀片受到的电磁力远大于背景气压造成的阻力时,增大驱动电流和增大背景气压都会加速流道口气体流动,提高气体注入量;电磁阀最高流速超过当地声速,流道应该设计成扩张式,且流道的长度要求尽可能短;电磁阀的注气持续时间主要由阀片的运动时间以及阀片关闭后气体在流道内扩散速率决定的。

Study on gas injection characteristics of a fast electromagnetic valve in electromagnetic plasma accelerator

In the measurement of a fast solenoid valve with short injection duration and high gas mass injection, the gas stagnation pressure is measured at the outlet of the solenoid valve using a high frequency pressure sensor, and the injected gas mass is measured by the vacuum chamber pressure difference before and after the gas injection. Studies show that driving current, displacement limits, and background air pressure have a significant effect on gas injection characteristics. When the valve plate electromagnetic force is much larger than the resistance caused by the background air pressure, the increase of the driving current and the background air pressure accelerate the gas flow in the flow channel and increase the gas injection mass. When the maximum gas flow rate exceeds the local sound speed, the flow channel should be tapered, and the flow channel length should be as short as possible. The gas injection duration is mainly determined by the valve plate movement time and the gas diffusion rate in the flow channel after the valve closes.