叶轮机湍流噪声的管道模态相干原理及物理机制研究

项目名称： 叶轮机湍流噪声的管道模态相干原理及物理机制研究

项目编号： No.51476134

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 能源与动力工程

项目作者： 乔渭阳

作者单位： 西北工业大学

项目金额： 75万元

中文摘要： 湍流宽频噪声既是未来航空发动机降噪设计的关键，也是目前自然科学领域研究的热点和难点。该申请项目以揭示航空叶轮机湍流噪声管道声模态随机特性和传播规律、构建湍流噪声源与管道声模态时空特征的数学关系为主要研究目的，研究航空叶轮机湍流噪声源识别理论和湍流噪声物理机制。应用湍流流场和声场数值模拟所获得的海量叶轮机湍流/噪声数据，辅助于轴流风扇流场/声场实验测量结果，以湍流噪声管道声模态统计分析理论为指导，以湍流噪声管道模态分解和识别为主要技术突破口，进行叶轮机湍流噪声理论和数值模拟的正问题研究和湍流噪声源分离识别的反问题研究，提高对叶轮机湍流噪声认识水平，发展完善叶轮机湍流噪声分析模型等，是本项目的研究特色和创新之处。本项目研究内容包括有关湍流噪声物理机制、随机噪声模态干涉理论、噪声源分离识别理论等流体力学和航空科学领域重要基础理论问题，其研究成果将为未来安静航空发动机设计奠定理论基础。

中文关键词： 气动声学；噪声控制；辐射噪声；叶轮机械；流体机械

英文摘要： After the obviously reduction of the rotor-stator interaction tone noise, turbomachinery turbulence broadband noise is now a major contributor to the noise emission of modern high-bypass-ratio turbofan engines in use on civil aircraft. Turbulence broadband noise is scattered while passing through the various rotor-stator stages present in turbomachinery components. Since these scattering processes depend on the modal content of the sound field, it is reasonable to decompose the acoustic field into modes to investigate the mechanism of turbulence broadband noise and to identify and separate the different broadband noise sources. Due to the complexity as well as the lack of investigation of the turbulence noise, the mechanisms responsible for turbulence noise and the statistical relation between radiation modes and turbulence source are still not perfectly understood and further studies are required.This study concerns the mode propagation and mode coherence functions of the turbulence broadband noise in the flow duct of turbomachinery. The turbulence and radiated noise will numerically simulated using the LES as well as the Goldaterin flow-duct aeroacoustic equation to obtain the modes of turbulence broadband noise. The turbulence flow-filed around rotor-stator and radiated sound in the inlet duct will be measured using 3D hot-wire and the microphone array on a high-loaded single-stage axial-flow fan. The turbulence broadband noise data from simulation and experiment will be compared, and the turbulence broadband noise modes will be statistical analyzed based on the random process theory. The technique that enables the separation of different stochastic noise sources in turbomachinery with respect to modal decomposition will be investigated. At last, the mechanism behind the turbomachiner turbulence broadband noise will be understood using the turbulence structure around blade as well as the modes decomposition in the inlet duct.

英文关键词： aeroacoustics;noise control;noise radiation;turbomachinery;duct sound