螺旋桨飞机舱室隔声技术研究

针对国内螺旋桨飞机的特点，重点对一实际飞机壁权进行了实验研究．实验结果表明，采用多层隔声结构、蜂窝刚度处理及阻尼处理、中间隔板及内装饰板弹性连接、附加声反射层等综合处理可以用较轻的重量代价获得较为理想的隔声效果．

On Reduction of Weight Needed for Sound Insulation Treatment of a Certain Chinese Propeller Airplane

Noise reduction in cabin of Chinese propeller airplane with sound insulation treatment often requires too much additional weight. In this paper, a special technique is presented which can achievenoise reduction with only a very much reduced additional weight. The key to the big weight reduction in additional weight is the introduction of a sound reflection layer, made of a aluminum foil0.1mm in thickness. This layer is fixed by a special technique on a carst-panel which is 0.4mm inthickness. It is believed that the use of such a reflection layer is never done before. In Fig.7, it can beseen that, as compared with ordinary sound insulation, the sound reflection layer can increase thesound transmission loss by 2-6 dB(2dB for low frequency noise, and 6dB for high frequency noise).Such a big increase in sound transmission loss is achieved at the cost of only an increase of0.73kg/ m2(wcight of carst-panel included). It is expected that this special technique, coupled withother conventional noise reduction measures,can achieve a total sound transmission loss of 16.5dB.