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类幼虫以高敏捷度旋转,使用接近雷诺兹数值的喷射来实现粘性主导
Ian K Bartol1, Alissa M Ganley1, Paul S Krueger2
1Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529, USA.
The Journal of experimental biology
|July 18, 2025
概括
年轻的类幼虫使用不同的喷射行为,在低雷诺兹数 (Re) 的水生环境中实现多功能转向. 它们的敏捷机动,包括手臂第一和尾巴第一的动作,对于对抗捕食者和导航的生存至关重要.
科学领域:
- 海洋生物学 海洋生物学
- 生物力学 生物力学
- 动物的运动 动物的运动
背景情况:
- 转对于海洋动物的生存至关重要,涉及捕捉猎物,躲避捕食者和导航.
- 之前关于转身表现的研究主要集中在成年游泳者身上,对早期发育阶段在较低的雷诺兹数下运行的理解有限 (Re).
- 年轻的头足动物,特别是类虫,生活在低RH的环境中,流体动力学对运动有很大影响.
研究的目的:
- 为了评估最近出的长海岸鱼 (Doryteuthis pealeii) 的转能力.
- 为了研究脉冲喷气推进在这些年轻的鱼的转向行为中的作用.
- 分析不同雷诺斯数 (Re) 和喷气特性如何影响等转动力学.
主要方法:
- 数字粒子图像速度测量 (DPIV) 用于分析直径喷气推进的流体动力学.
- 对游泳在观测室中的Doryteuthis pealeii虫进行了动力运动分析.
- 测量包括转向半径 (R/L平均),角速度 (Ω平均, Ω最大) 和喷流特性.
主要成果:
- 类幼虫表现出广泛的转向行为,包括手臂第一和尾巴第一的机动.
- 与较古老的鱼相比,Paralarval转的特点是更大的半径 (更低的转能力) 和更高的角度速度.
- 较高的喷气冲动与增加的角速度和位移相关;转向能力与雷诺兹数 (Re) 不同.
结论:
- 低雷诺兹数 (Re) 的环境需要鱼幼虫的多功能转向策略.
- 产生多样化的脉冲喷气的能力是抛物线转向多功能性和生存的组成部分.
- 双轮转动性能与成年鱼有显著差异,突出了运动中的本体遗传变化.
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