Liebeskind J G, Hanson R K, Cappelli M A
Appl Opt. 1993 Oct 20;32(30):6117-27. doi: 10.1364/AO.32.006117.
A diagnostic has been developed to measure velocity and translational temperature in the plume of a 1-kW-class arcjet thruster operating on hydrogen. Laser-induced fluorescence with a narrow-band cw laser is used to probe the Balmer α transition of excited atomic hydrogen. The velocity is determined from the Doppler shift of the fluorescence excitation spectrum, whereas the temperature is inferred from the lineshape. Analysis shows that although Doppler broadening is the only significant broadening mechanism, the fine structure of the transition must be taken into account. Near the exit plane, axial velocities vary from 4 to 14 km/s, radial velocities vary from 0 to 4 km/s, and swirl velocities are shown to be relatively small. Temperatures from 1000 to 5000 K indicate high dissociation fractions.
已开发出一种诊断方法，用于测量以氢气为燃料运行的1千瓦级电弧喷气推进器羽流中的速度和平移温度。使用窄带连续波激光器的激光诱导荧光来探测激发态氢原子的巴耳末α跃迁。速度由荧光激发光谱的多普勒频移确定，而温度则从谱线形状推断得出。分析表明，尽管多普勒展宽是唯一显著的展宽机制，但跃迁的精细结构必须予以考虑。在出口平面附近，轴向速度在4至14千米/秒之间变化，径向速度在0至4千米/秒之间变化，且旋流速度相对较小。1000至5000 K的温度表明解离分数很高。
