CAREER: Acoustic Radiation From Turbulent Premixed Flames: Fundamentals and Diagnostic Applications

在这项工作中，研究了控制火焰声辐射的基本流体力学和化学动力学，并利用这些知识开发了利用声学测量作为湍流火焰中热释放的高频诊断的能力。在广泛的雷诺数和达姆科勒数范围内进行了详细的流动和火焰特性研究。实验包括二维和三维速度场表征、用于确定火焰前沿特征的羟基平面激光诱导荧光(PLIF)以及使用麦克风和细丝热电偶的高频压力和温度测量。对不同的燃烧器直径和流速进行了测量，系统地评估了湍流速度和长度尺度对火焰噪声的影响，并在当量比、入口空气温度和燃料类型的范围内，评估了层流火焰速度、层流火焰厚度和Lewis数对声学特性的影响。

In this effort, the fundamental fluid mechanics and chemical kinetics that control acoustic radiation from flames are investigated, and, using this knowledge, the capability is developed for using acoustic measurements as a high-bandwidth diagnostic of heat release in turbulent flames. Detailed flow- and flame-characterization studies are performed over a wide range of Reynolds and Damkohler numbers. Experiments include two- and three-dimensional velocity field characterization, hydroxyl (OH) planar laser-induced fluorescence (PLIF) to determine flame-front characteristics, and high-frequency pressure and temperature measurements using microphones and fine-wire thermocouples. Measurements are made for different burner diameters and flow velocities to systematically assess turbulent velocity and length-scale effects on flame-generated noise, and also over ranges of equivalence ratio, inlet air temperature, and fuel type in order to assess the effects of laminar flame velocity, laminar flame thickness, and Lewis number on acoustic properties.