在雨滴碰撞后,木萨马拉恢复了自旋转
Breanna M Schaeffer1, Tadd T Truscott2, Andrew K Dickerson1
1Department of Mechanical, Aerospace, and Biomedical Engineering, University of Tennessee, Knoxville, TN 37996.
概括
萨马拉在飞行过程中对雨滴冲击表现出了显著的弹性. 这些种子始终恢复自旋转,确保有效的种子分散,尽管高速碰撞.
科学领域:
- 生物物理学的生物物理.
- 流体动力学 流体动力学
- 植物生物力学 植物生物力学
背景情况:
- 萨马拉表现出稳定的自旋转,这对于种子分散至关重要.
- 落的萨玛拉很容易受到高速雨滴的冲击,类似于飞行昆虫.
研究的目的:
- 为了研究雨滴与萨马拉碰撞的动态.
- 为了确定能够实现自旋回收的滴流机制.
- 分析碰撞位置和速度对萨马拉行为的影响.
主要方法:
- 详细分析了萨马拉体上的碰撞动态.
- 观察滴流机制和自旋回收.
- 量化投,滚动和冲击后恢复时间的量化.
主要成果:
- 冲击可以引起显著的斜率 (高达60度) 和跨度滚动.
- 跌落的行为有所不同:破碎,保持完整,或导致坚果碎片化.
- 翼尖撞击产生了最大的恢复距离;坚果撞击的破坏性最小.
- 更快的滴滴有助于更快的脱落和自旋回收 (<50毫秒).
结论:
- 萨马拉是非常坚固的雨滴冲击.
- 随着分散距离的最小减少,自旋转始终得到恢复.
- 滴流是一种关键的恢复机制,受冲击动态的影响.
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