运12飞机客舱降噪技术研究

 运12飞机客舱降噪取得了14 dB(A)的降噪效果,初步成功地改善了该机客舱恶劣的噪声环境。本文概要介绍在运12飞机客舱降噪研究中所提出的综合降噪处理技术,主要包括附加蜂窝刚度夹层结构、安装动力吸振器、改进窗结构设计、更换门窗边条封闭状态等。04架试验机降噪处理前后舱内声压级测量结果的比较,表明了综合降噪处理技术具有良好的降噪效果,而增重只有运12飞机重量的0.8％。

INVESTIGATION OF CABIN NOISE REDUCTION IN THE Yl2

More than 14 dB(A) in the highest cabin noise levels of the propeller-driven Y12 aircraft were reduced from the untreated condition. Thus, its interior higher noise environment is improved preliminarily and successfully. This paper deals with the noise control measures applied to the Y12 aircraft. It mainly includes the application of honeycomb sandwich stiffened panels, dynamic absorbers, damping treatments, window acoustic design and replacement of the windows and doors closure devices.The results of cabin noise levels in flight measurements are given for both acoustic pre- and aft-treated No. 4 Y12 aircraft. The analysis of the flight results shows that the noise control measures are effective. The added weight of the noise control package is about 0.8 percent of the total gross takeoff weight of the aircraft.