Abstract Droplet impact dynamics on super-hydrophobic micro-structured surfaces is vital in a multitude of processes such as spray coating, cooling, and inkjet printing etc. Majority of the research has been focused on the rebound phenomena while partial rebound is relatively underreported. Recent studies indicate that partial rebound is encountered where transition of wetting state may take place on super-hydrophobic surfaces. Herein, we report that satellite drops are formed during partial rebound of droplets even on hydrophobic surfaces with unidirectional topography created using a mask-less and stamp-less fabrication process. The simultaneous capillary driven retraction along the wrinkles and the strong contact line pinning across these anisotropic substrates leads to formation of satellite drops on hydrophobic surfaces. Excess rebound energy has been evaluated as functions of contact angle, contact angle hysteresis and the maximum spreading diameter to explain partial rebound on such surfaces with potential applications in the design of novel, functional surfaces.

中文翻译：

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单向结构疏水表面上液滴部分反弹过程中各向异性钉扎和液体性质的作用

摘要 超疏水微结构表面上的液滴冲击动力学在喷涂、冷却和喷墨印刷等众多工艺中至关重要。大部分研究都集中在回弹现象上，而部分回弹相对较少报道。最近的研究表明，在超疏水表面上可能发生润湿状态转变的地方会遇到部分反弹。在此，我们报告说，即使在具有使用无掩模和无印章制造工艺创建的单向地形的疏水表面上，在液滴的部分反弹过程中也会形成卫星液滴。同时毛细管驱动沿皱纹的回缩和固定在这些各向异性基底上的强接触线导致在疏水表面上形成卫星液滴。