An Experimental-Numerical Investigation of Unsteady Partially Premixed Flames

本文对部分预混烃-空气火焰的结构和稳定性的瞬态效应进行了实验和数值研究。在共流和逆流两种构型下，确定了稳定和非稳定火焰的主要反应途径及其对预混水平的依赖。研究了用一定振幅和频率的声强迫扰动内层对一氧化碳和氢的分布、反应速率和放热速率的影响。同样，扰动外层对点火和放热的影响也进行了量化。在共流和逆流火焰中进行了密封剖面和反应速率的参数比较。实验测量包括速度、种类、温度测量和火焰不稳定的高速摄像。

Abstract - Puri This is an experimental and numerical investigation of transient effects on the structure and stability of partially premixed hydrocarbon-air flames. The dominant reaction pathways, and their dependence on the elvel of premixing, are identified for both steady and unsteady flames in both coflow and counterflow configurations. The effects of perturbing the inner layer through acoustic forcing of specified amplitude and frequency on the distributin of carbon monoxide and hydrogen as well as on the reaction rates of these species and the heat release rates are examined. Similarly, the effects of perturbing the outer layer on ignition and heat release are quantified. Parametric comparisons between sealar profiles and reaction rates in coflow and counterflow flames are performed. Experimental measurements include velocity, species, temperature measurements, and high-speed videography of flame unsteadiness.