大型航空声学风洞消声室建设与校测

Anechoic chamber establishment and calibration of large scale aeroacoustic wind tunnel

风洞试验是进行民用飞机机体噪声研究的重要手段。为了满足航空飞行器低噪声设计在大型风洞中进行气动噪声试验的需求,中国航空工业空气动力研究院建设了FL-10大型低速风洞全消声室。通过在FL-10风洞试验大厅壁面安装吸声尖劈、对洞体外表面进行声学处理、对支撑系统进行隔声处理、对消声换气窗进行降噪处理等手段,建成了气动噪声风洞试验所需的声学环境。按照国家标准中给定的方法,利用张线方法实现了校准声源的布置,测量了消声室内沿不同路径、不同频率噪声的衰减规律,表明FL-10风洞消声室自由场特性达到了相应标准的要求,为后续在该风洞中进行大尺寸机体模型噪声试验奠定了基础。

FL-10 wind tunnel is the largest low speed return-flow wind tunnel in China so far,the aero-acoustic experiment ability was taken into consideration since the design period,a series of noise reduction design methods were applied ever since its construction.In order to meet the aero-acoustic wind tunnel requirement of aircraft low noise design,a large anechoic chamber was built and auxiliary equipment was acoustic treated to guarantee the acoustic environment of aero-acoustic wind tunnel experiment.The construction of FL-10 low speed wind tunnel aero-acoustic experimental environment,acoustic free field calibration and background noise measurement was introduced in this paper,the background noise level of FL-10 is presented.The free field calibration and background noise measurement results show that FL-10 wind tunnel has excellent aero-acoustic properties and capable of undertaking large size aero-acoustic experiments for the low noise design of aircraft.