当深腔分离剪切流动与其声学驻波特征相互耦合时，会产生强烈的噪音辐射和结构振动，甚至声疲劳破坏等严重问题。在相关流动管路布置规划中，必须谨慎规避深腔结构的涡声耦合问题；然而，目前对其耦合机理及影响因素的科学认识尚且不足，严重制约着相关工程设计水平。本项目将首先开展高频响TR-PIV和线列动态压力传感器的同步测量实验，获取高时空分辨率的深腔非定常流场。采用涵盖POD、EPOD和DMD等的先进流场数据分析体系，提取深腔涡声耦合旋涡结构的时空演变特征及其与驻波模态的动态相位响应关系。最后，通过基于霍尔气动声学理论的深腔涡声能量传递输运分析，获取旋涡结构时空演变过程、自持振荡流场与声学驻波场之间的能量传递输运过程。本项目的相关研究成果将揭示深腔分离剪切流动与其声学驻波模态之间的耦合机理，为抑制流激噪声和缓解声疲劳损伤等相关工程应用提供重要的理论指导。

The phenomenon of vortex-acoustic coupling is widely happened in the key components of industrial facilities, such as the lift system of an aircraft, the piping system of first loop of a nuclear power plant and the gas transport piping. The coupling between the separated shear flow inside the piping system with the acoustic standing wave of the deep cavity would bring severe problems to the industrial facilities, such as the aerodynamic noise, structural vibration and even acoustic fatigue damage. Present study focuses on the self-sustained oscillations of the aeroacoustically coupled flow field in a deep cavity, and tries to give an insight on the temporal-spatial evolutions of the coherent vortex structures, revel the relationship with the phase change of the acoustic standing wave, and delineate the energy transfer between the flow field and acoustic field. Towards this end, the synchronous measurement technique combining the high-frequency time-resolved PIV with the parallel dynamic pressure transducers are employed to capture the instantaneous flow field with high temporal-spatial resolution in the deep cavity. The advanced flow decomposition techniques, i.e. POD, EPOD and DMD, are used to identify, capture and quantify the dominant coherent structures. The Howe acoustic theory is used to analyze the energy transfer between flow field and acoustic field. The achievements of present study can provide the theoretical directions to control the aerodynamic noise and acoustic fatigue for the relevant industrial applications.