运载火箭发动机射流噪声载荷分析方法研究

The physical and mental heaths of the crews and experimenters on ground are endangered for the high intensity of jet noise load from the launch vehicle, which causes the fatigue failure or unexpected performance of the spacecraft and the facility for launch. In this project, a comprehensive and systemic research on the method of launch vehicle jet noise load measurement and analysis is conducted. First of all, aiming at the identification of the multi correlated sound sources with arbitrary distribution, a deconvolution method based on a microphone array in far field to identify the sound sources from the acoustic image is proposed. The microphone array signals measured in the far field of the engine jet are analyzed by that method to reconstruct the jet noise field, as well as the amplitude and distribution of the jet noise sources. Then aiming at simplifying the acoustic analogy mode in computational aeroacoustics, a jet noise simulation method based on virtual beamforming is proposed. It is such a simulation method that the data computed by computational fluid dynamics(CFD) can be directly fed into virtual beamforming algorithm to achieve the aeroacoustics computation. Finally, the jet noise load from the launch vehicle is studied by combining the measurement and simulation methods mentioned above to reveal the mechanism of the launch vehicle jet noise as well as the characteristic of that. The expected achievement from this project offers a complete analysis method to reveal the mechanism of the launch vehicle jet noise and its characteristic. Moreover the data basis of antinoise and anti-fatigue designs can be constructed based on the methods proposed in this project.

运载火箭高强射流噪声载荷危害着地面工作、实验人员的身心健康，引起航天器与地面发射设施的疲劳失效和工作异常。本课题针对运载火箭射流噪声载荷的测试和分析方法开展全面而系统的研究。针对任意分布多相关声源识别问题，提出基于远场传声器阵列的返解卷积声图像识别方法，能够通过在射流远场布置的传声器阵列进行测量，重构出近场射流噪声载荷幅值和分布情况；针对气动噪声数值仿真计算中的声类比模型简化问题，提出基于虚拟波束形成算法的射流噪声场仿真方法，能够实现利用流场数值计算结果直接进行气动噪声载荷分析，简化计算模型，节约计算成本；最后，结合前述实测和仿真方法，开展运载火箭发动机缩比模型射流噪声载荷研究，揭示运载火箭发动机射流噪声载荷机理，获得射流噪声载荷特征。本课题的预期研究成果为运载火箭发动机射流噪声载荷机理和特性的揭示，形成一套完整的分析方法，为新型运载火箭的抗噪声、疲劳和隔振降噪设计提供可靠的数据支撑。

本项目以起飞噪声环境获取为目标，探索基于传声器阵列的噪声源可视化方法和声阵列信号处理技术，在对常规波束形成、自适应波束形成，声反卷积、相关声源定位成像等噪声源可视化方法开展深入研宄的基础上，提出了改进的声反卷积相关声源定位方法，建立虚拟与实测相结合的噪声测试方法，并基于运载火箭发动机缩比模型射流噪声实验技术，对射流噪声载荷特征进行了分析. 本项目的研究成果能够为航天飞行器起飞噪声环境的测试与评价提供支撑。