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Updated: Jun 5, 2025

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波形几何学决定了动物的最佳巡航
Kazuko Yoshizawa1,2,3, Ryosuke Motani2
1Department of Earth and Planetary Science, University of Tokyo, Tokyo 113-0033, Japan.
Journal of the Royal Society, Interface
|December 10, 2024
概括
对于有效的游泳和飞行,最佳的斯特鲁哈尔数 (St) 范围取决于尾的功率效率.
科学领域:
- 生物力学 生物力学
- 流体动力学 流体动力学
- 动物的运动 动物的运动
背景情况:
- 脊椎动物和昆虫使用狭窄的斯特劳哈数 (St) 范围来实现高效的持续运动.
- 这种跨不同尺寸和流体的保护范围的原因仍然是一个.
- 以前的解释各不相同,缺乏统一的解释.
研究的目的:
- 提出并验证最佳斯特劳哈数 (St) 范围主要受尾尾翼尾边的功率输出效率的约束.
- 为了研究尾行边缘唤起动力学和推进效率之间的关系.
- 确定影响水上和空中的最佳巡航速度的因素.
主要方法:
- 开发一个数学模型,用于由尾行边缘产生的周期性唤醒.
- 分析功率损失的比例,而不是对推进有所贡献.
- 对各种与巡航鱼相关的雷诺德数的约束的评估.
- 整合形态特征和阻力特性.
主要成果:
- 数学模型预测鱼类在观察到的最佳斯特鲁哈尔数 (St) 范围内的最小能量损失.
- 这些功率效率约束适用于Reynolds数的范围.
- 该模型表明,这些约束,结合形态学,决定了各种生物体的最佳游泳和飞行速度.
- 定期波形的尾行边形几何被确定为巡航最佳性的关键因素.
结论:
- 尾尾翼的尾边的功率输出效率是最佳斯特鲁哈尔数 (St) 范围的主要限制.
- 这一发现为动物运动中保存的St范围提供了统一的解释.
- 这项研究为了解动物在液体中的运动以及生物灵感机器人设计提供了新的视角.
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