高性能风洞压缩机低噪声设计的流动和声学机理研究

As the main noise source of wind tunnel, the low-noise design of large axial-flow compressor is the key to effectively control the noise level of wind tunnel test section to meet the demand of the fine aerodynamic test in large transonic wind tunnel. The target of this project is to study the innovative theory and method of wind tunnel compressor noise control based on the principle of bionic flow noise control. This study focuses on fundamental investigation of innovative noise control strategies and mechanisms and, ultimately, to provide industries with applicable methodologies and technologies with a potential of achieving next step reductions in wind tunnel compressor noise generation and emission.. This project will study the flow and acoustic physical mechanism of the noise reduction of the tone generated by rotor-stator interaction and the broadband noise generated by the turbulence-blade interaction in axial flow compressor using experimentally measurement and numerically simulation. A series tests, include an open jet wind tunnel test on isolated blade, a compressor planar cascade test, and a single-stage axial-flow compressor test, will be comparatively investigated. The hybrid flow/acoustics simulation theory will be used to numerically simulate the flow field and acoustic in this study. A rod will be placed in front of the isolated blade and compressor planar cascade, and the interaction between the periodic shedding vortex in the rod wake and the blade is used to simulate the tone noise source on compressor blade, while the interaction between the rod wake turbulence and the blade is used to simulate the turbulent broadband noise source on compressor. The leading of the compressor blade will be remodeled with wave configurations to imitate the leading edge tubercles of pectoral flippers of humpback whales. The noise source identification method based on the “inverse method (Clean-SC)” of microphone array and the new hybrid URANS/FW-H and LES/FW-H aerodynamic noise simulation method which have been developed and validated in our group will be used in this study. With the hybrid URANS/FW-H aerodynamic noise simulation method, the tone of compressor with bionics configuration blade will be predicted and be compared with the experimental results. With the hybrid LES/FW-H aerodynamic noise simulation method, the turbulence broadband noise of the blade with bionics configuration will be predicted and be compared with the experimental results. The effects of various leading-edge configurations as well as the geometric parameter of the bionic configuration on the tone and broadband noise radiation noise reduction will be revealed and quantified in the study. The effects of the flow parameter such as Mach number, Reynoldes number, the ingested turbulence on the noise reduction in axial-flow compressor will also be experimentally and numerically investigated.. The goal of the current research is to understand the fundamental flow and acoustic mechanisms of tone reduction and broadband noise reduction for axial-flow compressor with bionic leading-edge configuration. From this research, it is hoped to find the key parameter to affect the noise reduction for axial-flow compressor with bionic leading- edge configurations. The experimental technology for the identification of flow-generated noise sources and the numerical modelling methodologies for robust analysis turbomachinery tone and broadband noise with a potential entering into the industrial routine in design and problem diagnosis, will also be improved and developed in this study. The development of innovative noise-reduction technologies and further improvement of up-to-date experimental and numerical methodologies will be useful for the breakthrough innovation of future low-noise fluid machinery.

大型跨声速风洞精细化试验的需求，对风洞试验段噪声控制提出了新需求和新挑战，大型轴流压缩机作为风洞主要噪声源，能否有效控制其噪声辐射直接关系着高性能风洞设计指标的实现。该项目正是以此重大需求为背景，将分别从轴流压缩机转静干涉单音噪声控制的流动和声学物理机制、轴流压缩机湍流-叶片干涉宽频噪声控制的流动和声学物理机制、以及高性能风洞轴流压缩机低噪声叶片设计原理和方法等几个方面，基于仿生学流动噪声控制原理，开展风洞压缩机噪声控制创新理论和方法研究。通过研究仿生学构型叶片设计对大型压缩机超长弦长叶片表面单音偶极子声源、对湍流-叶片干涉湍流宽频噪声源的影响，建立低噪声压缩机设计参数与压缩机降噪量的关联关系，发展大型压缩机低噪声仿生学叶片构型设计的声学模型等，掌握高性能风洞压缩机低噪声叶片气动声学设计理论和设计方法，为我国新一代高性能大型跨声速风洞建设奠定理论基础。

大型风洞实验是飞行器研制工作中的一项重要内容，随着飞行器设计水平的不断提升，对风洞实验段的流场品质提出了更高的要求。由于高强噪声会对非定常流试验、边界层转捩试验、激波-边界层干涉试验、湍流控制试验等产生显著影响，因此，风洞噪声已经成为影响风洞精细化流场试验成败的关键。轴流压缩机则是风洞主要噪声源，能否有效控制压缩机噪声已成为大型风洞设计建设中关键科学问题，直接关系着高性能风洞设计指标的实现。本项目正是以此重大需求为背景，开展大型风洞压缩机噪声控制创新理论和方法研究。. 解决目前对大型压缩机气动噪声特征和机理认识不清、低噪声设计方法匮乏等问题是本项目的研究重点，本项目以“师法自然”为灵感的仿生学流动控制为主要手段，分别从轴流压缩机转静干涉单音噪声控制的流动和声学机理、轴流压缩机转静干涉宽频噪声控制的流动和声学机理、高性能风洞轴流压缩机低噪声叶片设计原理和方法等方面，通过系统的数值仿真研究和实验分析研究，探索了低噪声构型压缩机叶片的设计原理及方法，深刻揭示了低噪声构型压缩机降噪的流动和声学物理机制。. 本项目首先发展了压缩机高保真流场/声场混合预测模型和方法，实现了压缩机精细化几何构型和精细化流场设计参数与与压缩机气动噪声的关联，显著提高了压缩机低噪声设计能力。本项目研究结果，弄清了大型风洞压缩机气动噪声的基本特点和随工作状况的变化规律，解决了目前对大型跨声速连续式风洞轴流压缩机声学特性认识匮乏、气动噪声预测能力不足等问题；深刻认识了压缩机叶片构型参数对压缩机转静干涉单音和宽频噪声影响的基本规律，揭示了压缩机叶片构型设计降低压缩机噪声的流动和声学物理机制。本项目将前沿的仿生学流动噪声控制理论应用于大型压缩机降噪设计，提出的“J型转子+C型静子+波浪型前缘静子”综合构型设计方法，实现了对压缩机单音和宽频噪声有效控制，突破大型压缩机低噪声设计的瓶颈。