谷仓猫头前端的相互作用与自由流流的相互作用
Alden Midmer1, Christoph Brücker1, Matthias Weger2
1City, University of London, Northampton Square 10, EC1V0HB London, United Kingdom.
Bioinspiration & biomimetics
|April 3, 2024
概括
草鸟翅膀纹通过控制空气流量来减少噪音. 这些羽毛结构被动地管理流,导致更安静的飞行,特别是在受影响的空气条件下.
科学领域:
- 生物力学 生物力学
- 流体动力学 流体动力学
- 生物声学是一种生物声学.
背景情况:
- 谷仓猫头表现出沉默的飞行归因于专门的翅膀羽毛.
- 关键特征包括有状的前边,软的背面和带的尾边.
研究的目的:
- 为了研究谷仓猫头翅膀尖端的空气动力学效应.
- 了解这些结构如何影响空气流和降低噪音.
主要方法:
- 从谷仓猫头羽毛扫描中创建了前沿纹的3D模型.
- 粒子图像速度测量 (PIV) 测量了空气流与流通道中的纹之间的相互作用.
- 流量条件包括稳定均的流入量和自由流流动的流入量.
主要成果:
- 纹诱导了规律的速度条纹和流动在均的流动中转动.
- 塞拉斯在遇到流时显著减少了下游流动波动.
- 观察到流量均化,特别是跨度速度组件.
结论:
- 谷仓猫头的尖端纹作为一个被动的流量控制机制.
- 这些结构有效地减少动荡环境中的尖端噪声.
- 这些发现为生物启发的降噪策略提供了洞察力.
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