基于紫外激光的羟基-平面激光诱导荧光探测研究进展

Research progress of hydroxy-plane laser-induced fluorescence detection based on ultraviolet laser

羟基(OH)是一种广泛存在于燃烧反应过程中的产物,在燃烧诊断技术中,基于羟基的二维空间分布常用于表征火焰的锋面结构,同时羟基也是表征火焰温度、火焰面密度和热释放速率等特征的重要参数。对燃烧火焰中的羟基进行有效探测是探究燃烧动力学演变过程,揭示火焰随机事件产生机理的重要支撑。平面激光诱导荧光(PLIF)技术作为一种光学测量方法,具有时空分辨率高、无干扰、可进行组份选择等优点,已成功用于对本生灯火焰、湍流火焰、旋流火焰和超声速火焰等多种燃烧火焰进行结构观测,为建立燃烧模型提供了重要参考。本文从PLIF探测的基本原理开始,梳理了PLIF技术在燃烧诊断领域的发展历程和研究现状,介绍了基于染料激光、光参量振荡和钛宝石三倍频方式实现的PLIF紫外光源技术,并对不同技术路线的特点进行了讨论,最后对用于OH-PLIF的紫外激光技术发展进行了展望。

Hydroxyl(OH)is a widely existing product in the combustion reaction process.In combustion diagnosis technology,the two-dimensional spatial distribution based on hydroxyl is commonly used to characterize the structure of the flame front.Hydroxyl is an important parameter in characterizing the flame temperature,flame surface density,and heat release rate.The effective detection of hydroxyl in combustion flame is an important support for exploring the evolution of combustion dynamics and revealing the mechanism of random flame events.Planar laser-induced fluorescence(PLIF)has several advantages as an optical measurement method:high spatial and temporal resolution,non-intrusiveness,and component selection.PLIF has successfully observed the structure of various combustion flames,such as Bunsen burner flame,turbulent flame,swirl flame,and supersonic flame,which provides an important reference for establishing combustion models.This paper starts with the basic principle of PLIF detection,followed by the development history and research status of PLIF technology in the field of combustion diagnosis.Then,it introduces the PLIF ultraviolet light source technology based on dye laser,optical parametric oscillation,and Ti:sapphire tripling-frequency,and discusses the characteristics of different technical routes.Finally,it prospects the development of UV laser technology for OH-PLIF.