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游泳速度的变化对人类水下波浪式游泳的尾流动力学的影响
Yusaku Nakazono1, Hirofumi Shimojo2, Yasuo Sengoku3
1Graduate School of Comprehensive Human Sciences, Doctoral Program in Physical Education, Health and Sport Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan.
Journal of biomechanics
|February 29, 2024
概括
增加下肢运动速度可以提高水下波浪式游泳 (UUS) 的速度. 这项研究表明,较高的流速增加了脚速度,并在下到上过渡期间优化了旋动力学,从而提高了动量.
科学领域:
- 生物力学 生物力学
- 流体动力学 流体动力学
- 运动科学 运动科学 运动科学
背景情况:
- 提高水下波浪式游泳 (UUS) 速度是表现的关键.
- 将下肢运动与游泳速度联系在一起的精确机制仍然不完全理解.
研究的目的:
- 阐明下肢运动特征与由此产生的流场动态之间的关系.
- 为了研究流速变化如何影响UUS动力学和水力动力学.
主要方法:
- 使用了三种流速设置 (0.8,1.0,1.2 m/s) 的水流.
- 使用运动捕捉用于下肢运动分析.
- 应用立体粒子图像速度计 (PIV) 来可视化唤醒流.
主要成果:
- 增加的流速与所有流向 (u, v, w) 的更高速度向量相关,并增加了脚速度.
- 在下和上阶段,脚速度向量的特定变化似乎对 vortex 形成产生了积极的影响.
- 在向下到上过渡期间观察到高流速的旋重新捕获,这表明动量增强.
结论:
- 这项研究首次确定了运动和流场因素,这些因素有助于增加UUS速度.
- 优化下和上阶段之间的过渡对于最大限度地提高游泳势头至关重要.
- 了解这些生物力学和水力动力学相互作用可以为UUS提供培训策略.
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