The motion of a water droplet in a hydrophobic wedge fixture was examined to assess droplet rolling and spinning for improved dust mitigation from surfaces. A wedge fixture composed of two inclined hydrophobic plates had different wetting states on surfaces. Droplet rolling and spinning velocities were analyzed and findings were compared with the experiments. A wedge fixture was designed and realized using a 3D printing facility and a high speed recording system was adopted to evaluate droplet motion in the wedge fixture. Polycarbonate sheets were used as plates in the fixture, and solution crystallization and functionalized silica particles coating were adopted separately on plate surfaces, which provided different wetting states on each plate surface while generating different droplet pinning forces on each hydrophobic plate surface. This arrangement also gave rise to the spinning of rolling droplets in the wedge fixture. Experiments were extended to include dust mitigation from inclined hydrophobic surfaces while incorporating spinning- and rolling droplet and rolling droplet-only cases. The findings revealed the wedge fixture arrangement resulted in spinning and rolling droplets and spinning velocity became almost 25% of the droplet rolling velocity, which agrees well with both predictions and experiments. Rolling and spinning droplet gave rise to parallel edges droplet paths on dusty hydrophobic surfaces while striations in droplet paths were observed for rolling droplet-only cases. Spinning and rolling droplets mitigated a relatively larger area of dust on inclined hydrophobic surfaces as compared to their counterparts corresponding to rolling droplet-only cases.

中文翻译：

---

V 形疏水表面中的液滴滚动和旋转以减轻环境粉尘

检查疏水楔形夹具中水滴的运动，以评估水滴滚动和旋转，以改善表面灰尘的减少。由两个倾斜疏水板组成的楔形夹具在表面具有不同的润湿状态。分析了液滴滚动和旋转速度，并将结果与​​实验进行了比较。使用 3D 打印设备设计并实现了楔形夹具，并采用了高速记录系统来评估楔形夹具中的液滴运动。夹具中采用聚碳酸酯板作为板，板表面分别采用溶液结晶和功能化二氧化硅颗粒涂层，在每个板表面提供不同的润湿状态，同时在每个疏水板表面产生不同的液滴钉扎力。这种布置也引起了楔形夹具中滚动液滴的旋转。实验扩展到包括从倾斜的疏水表面减轻灰尘，同时结合旋转和滚动液滴以及仅滚动液滴的情况。研究结果表明，楔形夹具布置导致液滴旋转和滚动，旋转速度几乎达到液滴滚动速度的 25%，这与预测和实验都非常吻合。滚动和旋转液滴在多尘的疏水表面上产生平行边缘液滴路径，而在仅滚动液滴的情况下观察到液滴路径中的条纹。与对应于仅滚动液滴的情况相比，旋转和滚动液滴减轻了倾斜疏水表面上相对较大的灰尘区域。