发射光谱测量电弧加热发动机羽流温度

Temperature measurement of arcjet plume with emission spectrum

为了研究玻耳兹曼图法和谱线绝对强度法对测量结果的影响,讨论了电弧加热发动机羽流的光谱诊断方法,并建立了一套光谱诊断系统.以氩气为工质,利用此系统在真空室中进行了光谱诊断,分别用玻耳兹曼图法和谱线的绝对强度法得到了羽流的温度,这两种方法测得的结果有20%～30%的偏差.实验中氩气流量为42.1mg/s,功率约为200W.试验结果表明,在试验工况下,由于羽流处在热力学非平衡态,采用玻耳兹曼图法和谱线的绝对强度法得到的结果是不同的,应该根据具体的工况选择测量方法.

To determine the difference of the measurement results from different measuring methods, diagnostic principle for arcjet plume was discussed and a set of spectral diagnostic system was established. With this system, spectrum diagnostic was executed for Argon propellant with the flow-rate of 42.1 mg/s and the input power about 200 W, and the temperature was deduced with Boltzmann diagram method and absolute intensity method respectively. There is a 20% to 30% discrepancy in the temperature values of the two methods. The experimental result shows that Boltzmann diagram method and absolute intensity method may lead to different temperature due to the appearance of thermal nonequilibrium. Therefore, actual working condition should be considered to specify the measurement method.