We investigate herein the impact of helical structures on the motion of asymmetrical droplets along vertically twisted fibers. The droplet adopts helical motion around the bundle driven by gravity. This complex motion can be manipulated by varying the twists turns of the fibers. When the droplet size is smaller than the characteristic length of the helix (pitch), the droplet adopts a predominant helical motion correlated to the groove of the twisted fibers. When the droplet size exceeds the pitch length, a mixed motion of intermittent vertical sliding and helical movement emerges. A model describes rotational and linear speeds as a function of the number of fiber twist turns. This research highlights the profound role of substructures in droplet dynamics, offering fresh insight into droplet manipulation or fiber-based devices.

中文翻译：

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加捻纤维上的液滴螺旋运动


我们在此研究了螺旋结构对不对称液滴沿垂直加捻纤维运动的影响。液滴在重力作用下围绕线束采用螺旋运动。这种复杂的运动可以通过改变纤维的扭曲和转弯来操纵。当液滴尺寸小于螺旋线的特征长度（螺距）时，液滴采用与加捻纤维的凹槽相关的主要螺旋运动。当液滴尺寸超过节距长度时，会出现间歇性垂直滑动和螺旋运动的混合运动。模型将转速和线性速度描述为纤维扭曲匝数的函数。这项研究强调了子结构在液滴动力学中的深远作用，为液滴操作或基于纤维的器件提供了新的见解。