紫外像增强器在航空发动机燃烧诊断中的应用

Application of Ultraviolet Image Intensifiers in Combustion Diagnostics of Aero-engines

航空发动机燃烧过程中,OH^(*)、NO^(*)、NH^(*)等激发态自由基伴随着紫外波段的微弱自发光,且随燃烧的进程而快速变化。紫外像增强器最高具有百万倍电子增益、纳秒量级快门,可以实现紫外波段燃烧流场瞬态结构的捕获,为定量化测量、阐释燃烧特性随多物理参数的变化规律奠定基础。本文总结紫外像增强器在航空发动机燃烧光学诊断中的应用,包括针对OH^(*)自发光进行成像的被动光学诊断技术、利用激光激发OH成像的主动光学诊断技术等。最后,结合新型航空发动机高时空分辨探测的要求,指出紫外像增强器在燃烧诊断中的发展方向。

In the combustion process of aero-engines,excited-state free radicals such as OH^(*),NO^(*),and NH^(*)emit faint self-chemiluminescence in the ultraviolet(UV)band,which changes rapidly with the progress of combustion.UV image intensifiers,featuring up to a million-fold electronic gain and nanosecond-level shutter speed,can capture the transient structure of the combustion flow field in the UV band,laying the foundation for the quantitative measurement and interpretation of the variation rules of combustion characteristics with multiple physical parameters.This paper summarizes the application of UV image intensifiers in optical diagnostics of aero-engine combustion,including passive optical diagnostic techniques for imaging OH^(*)self-chemiluminescence,and active optical diagnostic techniques using laser excitation for OH imaging.Finally,