电弧风洞真空氩气起弧技术研究

为解决传统金属丝熔融法起动电弧风洞准备时间长、可靠性差、熔渣影响设备安全和参数测试等问题，研究分析了电弧风洞采用真空氩气起弧技术起动的可行性。通过试验对比分析了起弧间距、进气方式以及控制时序等参数对电弧风洞起动特性的影响，利用一级触发、逐级拉弧的方式实现数米长电弧加热器的安全起动。结果表明，真空氩气起弧技术可以稳定、可靠、快速起动电弧风洞；起弧间距为25mm时，起动时间短，平均电流低，设备烧损小，起动最可靠；采用阴极尾部通氩气的进气方式，起动稳定、操作方便、维护简单；该起弧技术具有最佳的控制时序，确保了起动稳定可靠。

Auto-ignition investigation with low-pressure argon stream for arc heated wind tunnel

The auto-ignition with low-pressure argon stream used to ignite the arc heated wind tunnel is investigated,in order to overcome the disadvantage of the conventional ignition method, which has a long preparing time,poor reliability and safety in operation.The effects of electrode gap,gas supply way and ignition sequence on ignition performance were examined experimental-ly.Arc heater with the length of several meters was ignited first by breakdown of argon between short electrode gaps at trigger voltage and then arc elongate to anode with the close of switches in sequence .It was indicted that arc heated wind tunnel could be easily ignited with low-pressure ar-gon stream by the way of step trigger.When the electrode gap is 25mm,the ignition performance is the best,whose start time is the shortest and start arc current is the lowest.Ignition gas argon should be injected in the rare of arc heater,which could reliably ignite arc heated wind tunnel and have several advantages in operation and maintenance.And a good ignition sequence used in arc heated wind tunnel was also suggested.