Scattering and Excitation of Acoustic Waves by Turbulent Flames

这是紊流火焰对声波的激发和散射的理论研究。具体地说，它检验了不同粗糙度尺度的运动的、卷曲的火焰锋面的声辐射特性。它还研究了散射波和激波的空间和时间特征如何被用作湍流火焰锋面的诊断。本研究采用耦合积分方程方法对声场进行分析。完全解需要两个这样的方程的解，描述火焰的上游和下游的场，它们是由质量、动量和能量守恒条件耦合的。在某些极限情况下得到解析解，而在解析难解情况下采用数值边界元方法。这项工作补充了一项对相同现象的实验研究，该研究得到了对主要研究者的CAREER奖的支持。

This is a theoretical investigation of the excitation and scattering of acoustic waves by turbulent flames. Specifically, it examines the acoustic radiation characteristics of moving, convoluted flame fronts of various scales of roughness. It also looks at how the spatial and temporal characteristics of the scattered and excited waves can be used as a diagnostic of turbulent flame fronts. The study uses a coupled integral equation approach to analyze the acoustic field. The complete solution requires the solution of two such equations, describing the field upstream and downstream of the flame, that are coupled by mass, momentum, and energy conservation conditions. Analytical solutions are obtained in certain limiting cases, while a numerical boundary-element approach is used for analytically intractable cases. This effort complements an experimental study of the same phenomena supported by a CAREER award to the principal investigator.