Rotational propulsion enabled by inertia
Rotational propulsion enabled by inertia
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DOI：
10.1140/epje/i2014-14060-y
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发表时间：
2014-07
期刊：
影响因子：
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通讯作者：
F. Nadal;O. S. Pak;Lailai Zhu;L. Brandt;E. Lauga
中科院分区：
文献类型：
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作者：
F. Nadal;O. S. Pak;Lailai Zhu;L. Brandt;E. Lauga
摘要：小规模运动的流体力学最近引起了相当大的关注，因为它在细胞运动和用于生物医学应用的人造微型游泳器的设计中具有重要意义。关于该主题的大多数研究都考虑零雷诺数的理想极限。在本文中，我们研究了一种简单的推进机制——一个绕其对称轴旋转的上下不对称哑铃——在牛顿流体中没有惯性的情况下无法推进。对于雷诺数的所有有限值，惯性力都会产生连续的推进力。我们通过计算研究其推进特性，并在小雷诺数限制下进行分析。我们还推导出最佳的哑铃几何形状。惯性引起的推进方向与粘弹性引起的推进方向相反。图形摘要
AbstractThe fluid mechanics of small-scale locomotion has recently attracted considerable attention, due to its importance in cell motility and the design of artificial micro-swimmers for biomedical applications. Most studies on the topic consider the ideal limit of zero Reynolds number. In this paper, we investigate a simple propulsion mechanism --an up-down asymmetric dumbbell rotating about its axis of symmetry-- unable to propel in the absence of inertia in a Newtonian fluid. Inertial forces lead to continuous propulsion for all finite values of the Reynolds number. We study computationally its propulsive characteristics as well as analytically in the small-Reynolds-number limit. We also derive the optimal dumbbell geometry. The direction of propulsion enabled by inertia is opposite to that induced by viscoelasticity.Graphical abstract