领先的旋改善了缓慢飞行的蝙蝠的升力
F T Muijres1, L C Johansson, R Barfield
1Department of Theoretical Ecology, Lund University, SE-223 62 Lund, Sweden.
概括
蝙蝠和昆虫一样,使用不稳定的空气动力学来飞行. 这项研究表明,食花蜜的蝙蝠使用前沿 (LEVs) 来提高飞行能力来产生升力.
科学领域:
- 空气动力学 航空动力学
- 生物力学 生物力学
- 动物学 动物学
背景情况:
- 准稳定状态空气动力学理论表明,缓慢飞行的脊椎动物无法产生足够的升力.
- 建议使用不稳定的空气动力学机制,以增强在飞行时的升力产生.
研究的目的:
- 为了研究一种食花蜜的蝙蝠在缓慢前进飞行中产生的升力.
- 为了确定蝙蝠是否使用不稳定的空气动力学机制,特别是前沿流 (LEV).
主要方法:
- 数字粒子图像速度测量 (DPIV) 用于分析空气流动模式.
- 测量是在缓慢前进飞行的一个小蜜食蝙蝠.
主要成果:
- 蝙蝠使用附着的前沿 (LEV) 增加了高达40%的升力.
- 实现了4.8的最大提升系数.
- 空气流的重新连接顺利地发生,尽管攻击角度高和机翼曲.
结论:
- 不稳定的空气动力学机制,如LEVs,对于蝙蝠飞行至关重要.
- 在飞飞行中使用LEV的范围不仅仅是昆虫,还包括更大的动物.
- 蝙蝠采用先进的空气动力学策略,以高效地悬浮和缓慢飞行.
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