悬浮的蜂鸟的空气动力学
Douglas R Warrick1, Bret W Tobalske, Donald R Powers
1Department of Zoology, Oregon State University, 3029 Cordley Hall, Corvallis, Oregon 97331, USA. warrickd@science.oregonstate.edu
Nature
|June 24, 2005
概括
与昆虫不同的是,蜂鸟在下行过程中产生了大部分的悬浮升力. 这种由翼逆转驱动的力不对称性,尽管在动力学上有相似之处,但它区分了鸟类的飞行.
科学领域:
- 生物力学 生物力学
- 空气动力学 航空动力学
- 鸟类学 鸟类学是一门学科.
背景情况:
- 蜂鸟 (Trochilidae) 经常被认为使用类似昆虫的空气动力学机制来悬浮.
- 蜂鸟翅膀跳动的动力对称性表明,在上升和下降过程中产生相同的升力.
- 这种假设影响了空气动力学模型和鸟飞行的实证研究.
研究的目的:
- 为了研究在蜂鸟中悬浮时的力产生不对称性.
- 将蜂鸟的空气动力学机制与昆虫的空气动力学机制进行比较.
- 分析翅膀动力学和形态学在鸟飞行中的作用.
主要方法:
- 数字粒子图像速度测量 (DPIV) 用于测量悬浮的色蜂鸟 (Selasphorus rufus) 的尾巴.
- 分析的重点是唤醒结构以推断空气动力学力.
- 机翼动力学和形态学被认为与力量产生有关.
主要成果:
- 蜂鸟表现出显著的力量不对称性,在下行时产生75%的重量支,在上行时产生25%的重量支.
- 在上升过程中翼的反转可能会导致这种力不对称.
- 在下行过程中观察到的尖端旋表明在低雷诺兹数下运行,类似于昆虫.
结论:
- 蜂鸟悬浮的特点是力量不对称,与上下冲动的假设相同贡献形成鲜明对比.
- 尽管旋动力学与昆虫有相似之处,但由于鸟类的体型,蜂鸟的飞行是截然不同的.
- 这项研究突出了蜂鸟使用的独特空气动力学策略.
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