项目名称： 声学风洞传声器阵列测试的射流剪切层修正技术研究

项目编号： No.11504417

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 张军

作者单位： 中国空气动力研究与发展中心

项目金额： 24万元

中文摘要： 目前我国正在研制大型民用客机，准确测量机体噪声源分布，开展相应的噪声评估和降噪研究，使我国大型民用客机噪声水平满足最新的国际民航组织标准，对我国大型民用客机跻身国际市场具有非常重要的意义。在声学风洞开口试验段内，利用传声器阵列测量飞机气动噪声源会遇到射流剪切层干扰的问题，即当声波透过剪切层后其相位和幅值将发生改变，使得阵列测量值和真实值发生偏差，从而不利于噪声源的准确定位和噪声级的准确评估，因此亟需发展相关技术对传声器阵列测量进行修正。本项目涉及的物理过程和理论问题主要包括：噪声信号与射流剪切层界面的相互作用，声波在含湍流的剪切层内部的传播，以及传声器阵列对声信号的处理等。本项目旨在建立射流剪切层内外气动噪声传播的理论模型和计算模型，探讨瞬态流场变化与传声器阵列接收点处声场模式改变的关系，为实现声学风洞内传声器阵列准确测量噪声源奠定坚实的理论基础和技术基础。

中文关键词： 噪声源；波束成形；噪声源定位

英文摘要： Currently we are developing large civil aircraft. The accurate measurement of airframe noise distribution, carrying out corresponding research on noise level assessment and noise control method, making the large civil aircraft satisfy the newest ICAO standards, are very important for our large civil aircraft to be competitive in the international market. In the open-jet test section of an anechoic wind tunnel, the shear layer problem should be noticed when localizing the noise source with microphone array technology. The shear layer will make the measured data deviate from the true value, which is harmful to accurately identify the noise source position and evaluate the noise source level. Therefore, it’s very necessary to develop an effective method to correct the shear layer influence. The physical process and theoretical problem involved in the project including: the interaction of noise signal and the boundary of shear layer, the propagation of sound wave in the shear layer which consists turbulences and vortexes, and the processing of acoustic signal received by microphone array elements. This project is aimed at building theoretical and computational model for sound wave in and out of the shear layer, discussing the relationship between transient flow field variation and the sound mode change at the reveiving point of microphone sensors, laying a solid foundation for the precise measurement of aero-acoustic noise using microphone array.

英文关键词： noise source ;beamforming ;noise source localization