CH4/Air反扩散射流火焰多组分同步PLIF诊断

多组分同步平面激光诱导荧光技术在研究火焰结构和燃烧反应中间产物二维分布等方面有着重要作用。为了研究CH₄-Air反扩散射流火焰，搭建了OH/CH₂O/丙酮（Acetone）多组分同步平面激光诱导荧光实验系统。系统由2套激光器、2部ICCD相机、1组时序控制器以及光学系统构成。通过对不同组分物质分子有效激发策略、时序控制方法以及双ICCD成像技术进行了分析，最终实现了对火焰反应区、预热区以及燃料分布区域等火焰结构信息瞬态测量及可视化。基于该实验系统，对反扩散射流火焰进行了实验研究。研究结果表明，反扩散射流火焰形式既不同于传统的预混火焰，也不同于常规的扩散火焰，更多表现为部分预混的扩散火焰；较之OH*化学发光成像，多组分平面激光诱导荧光结构更能准确认识火焰的基本形态和燃烧模式，在基础燃烧和工业研究中都具有重要的应用价值。

Simultaneous multi-species PLIF diagnostic on CH4-Air inverse diffusion jet flame

The simultaneous multi-species Planar Laser Induced Fluorescence technique plays an important role in studying the flame structure and the two-dimensional distribution of intermediate species in combustion.The experimental system of OH/CH₂O/Acetone-PLIF was built in order to study the CH₄-Air inverse diffusion jet (IDJ) flame.The system consists of two sets of lasers, two intensifier-CCD cameras, a temporal controller and several lenses.The strategy of fluorescence excitation, the method of synchronous timing control and image calibration procedures are discussed.The IDJ flame was studied using the simultaneous multi-species PLIF technique, and the reaction zone, pre-heating zone and fuel zone of IDJ flame were determined.Experimental results suggest that the IDJ flame is different from either the normal diffusion flame or the premixed jet flame.The behavior of this type of flame reveals similarity to the partially premixed flame.Compared to OH chemilumiscence images, simultaneous multi-species PLIF can provide more detail and information about the flame structure and it has huge potential in fundamental combustion studies and industrial burner experiments.