飞机壁板附加动力吸振器后的振动与声辐射

本文运用模态分析方法系统分析了飞机壁板附加动力吸振器前后的结构振动特性，推导出了动力吸振器减振降噪量公式，并对动力吸振器各能数以及安装位置对其减振降噪效果的影响进行了分析和讨论。在此基础上设计了适合于飞机壁板安装的动力吸振器，并进行了实验室实验和飞机了飞行试验。结果表明，动力吸振器用于抑制飞机壁板的振动与声辐射具有良好的前景。

On Vibration and Sound Radiation of Aircraft Panel Equipped with Dynamic Vibration Absorbers

Dynamic vibration absorber attached to aircraft panel is effective in reducing propeller-induced cab- in noise of propeller-driven aircraft.Thus far theoretical analysis is still not quite adequate.By means of modal analysis,the authors analyze systematically vibration and sound radiation of aircraft panel and de- rive formulas for vibration reduction and noise reduction respectively,obtainable when dynamic vibration absorber is employed.These formulas make it possible to discuss the effects of various parameters and po- sition of installation of absorber on vibration and noise reduction.Then general principles are offered for selecting proper values of parameters and proper position of installation.Laboratory tests show that theo- retical predictions agree well with test data.In the flight test of a propeller-driven aircraft,the authors,in cooperation with engineers in industry and reseachers in a reseach institute,obtain preliminarily satisfac- tory reduction of noise.Of course,theoretical work needs to be further refined in order to take into con- sideration as nearly as possible all the complications present in a real aircraft.