基于相控麦克风阵列的民机主起落架气动噪声源识别技术研究

Aerodynamic noise source detection for main landing gear based on phased microphone array technique

起落架气动噪声是民机机体噪声极为重要的组成部分。由于起落架结构外形复杂,同时各部件之间干扰严重,使得其噪声机制十分复杂。目前,相控麦克风阵列技术已经成为识别民机机体噪声声源位置最为常用和可靠的技术手段。结合闭口声学风洞试验数据,采用经典的Beamforming算法,分析对比了民机主起落架构型在不同频率下声源位置分布情况,获得了不同频率下的最大声源位置;采用CLEAN-PSF算法剔除主起舱门位置处的声源,抑制了最大声源旁瓣对其他声源位置遮盖效应。

Landing gear noise is one of the most important parts of the aircraft ~s airframe noise. Due to the geometry complexity of the landing gear devices, as well as the interference effects on the flows surrounding the parts of the landing gear, the noise mechanism of the landing gear is extremely complicated. Currently, the phased microphone array is one of the most popu- lar methods to detect the location of the acoustic source of the airframe noise. After acquiring the noise source data in a closed wind tunnel, the Beamforming are adopted to localize the exact noise source locations at different frequencies. In order to avoid the cover effect of side-lobes of the maximum noise source location, CLEAN-PSF algorithm is employed to cut out the noise source location at the main door.