猫头鹰的静音飞行机理研究 Study on Mechanism of Silent Flight of Owls

猫头鹰在所有鸟类中飞行噪声最低，这一现象引起了鸟类学家、声学专家甚至军事专家的极大兴趣。本文首先测试了猫头鹰的飞行噪声特性，进而对猫头鹰翅膀翼型的宏观形态特征以及气动和声学特性，猫头鹰体表羽毛的微观结构特征和力学特性，猫头鹰体表皮肤和皮下结构的微观结构特征及其吸声特性开展了较为系统的研究，发现猫头鹰独特的静音飞行能力实际上是源于多个降噪因素综合产生的总体效应，是消声降噪和吸声降噪两种机制的共同作用，这对于研究减振降噪技术有着极为重要的启发意义和参考价值。 The silent flight of owls has long fascinated ornithologists, acoustic specialists, and even military experts; no other birds fly with such distinct advantages. In this work, the flight noise of a bubo bubo (a kind of large owl) was recorded, and followed by a comprehensive study on the mechanism of the silent flight, including research on the wing profile and its aerodynamic performance and acoustic property, the morphology of the feathers and its mechanical characteristics, as well as the microscopic structure of the skin and its sound absorption performance. It is concluded that the unique ability of silent flight of owls attributes to the combination of multiple noise reduction factors, sorted as sound suppression and sound absorption, which has piqued the interest of biomimetic research for noise control.