鱼类的绘制行为是由水翼模型周围局部压力下降引起的
Go Eguchi1, Tsutomu Takagi2, Shinsuke Torisawa3
1Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1, Minato-cho, Hakodate, Hokkaido 041-8611, Japan.
Journal of theoretical biology
|April 22, 2024
概括
鱼类通过使用翼来表现出"起草"行为.
科学领域:
- 流体动力学 流体动力学
- 生物力学 生物力学
- 水力动力学就是水力动力学.
背景情况:
- 鱼群培养通过流场相互作用提高了水力动力推进效率.
- 鱼类的节能行为与结构引起的流场变化有关.
- 了解鱼的结构相互作用是理解高效运动的关键.
研究的目的:
- 为了研究与单独游泳相比,在精简的潜翼模型附近的活鱼游泳行为的差异.
- 分析鱼类"起草"行为背后的机制,鱼类在没有尾巴打动的情况下保持静止.
- 为了确定鱼类如何利用流场的修改和身体的方向来实现力量平衡和推进.
主要方法:
- 观测活鱼游泳行为在一个流动的水翼模型在一个流动的水箱周围.
- 分析鱼的拖动行为,包括推力产生和力平衡.
- 模型实验使用双轴负载单元和计算模拟来验证结果.
主要成果:
- 鱼类表现出"起草"的行为,通过利用翼附近的局部压力下降来保持静止,而不会使尾巴打动.
- 鱼类从靠近翼的高速流动中获得推力 (攻击角度10°20°) 没有流动分离.
- 模型实验和模拟证实,鱼体的攻击角度产生起重,以抵消吸力,有效平衡力.
结论:
- 鱼可以通过平衡前后和侧面的力量来实现起草.
- 这种平衡是通过利用水翼周围的局部压力下降作为吸力来实现的.
- 鱼体的攻击角度在产生起重力和抵消力方面发挥着至关重要的作用,从而使能耗高的机动运动成为可能.
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