论文标题
卡斯 - 巴克斯特液滴如何以及何时开始在纹理表面上滑动
How and When the Cassie-Baxter Droplet Starts to Slide on the Textured Surfaces
论文作者
论文摘要
卡斯 - 巴克斯特状态液滴在纹理表面上具有许多局部能量最小值，而它们之间的能量屏障的量可能会受到重力的影响。当液滴找不到表面上的任何局部能量最小点时，液滴开始滑动。基于拉普拉斯压力方程，预测纹理表面上二维Cassie-baxter液滴的形状。然后，通过考虑液体和表面微观结构之间的干扰以及分析脱机时的自由能变化来检查液滴的稳定性。之后，对基于线压的前跟踪方法模拟（LTM）进行了理论分析，该方法无缝捕获液体和底物之间的附着和脱离。我们回答了在滑动研究领域的开放辩论：（i）滑动启动是通过前端滑动或后端滑动的启动，以及（ii）在水平表面上测得的前进和后退接触角是否与滑动片开始时滴头的前后触点角相当。此外，提出了一种由凝结和蒸发循环提升的新液滴翻译机制。
The Cassie-Baxter state droplet has many local energy minima on the textured surface, while the amount of the energy barrier between them can be affected by the gravity. When the droplet cannot find any local energy minimum point on the surface, the droplet starts to slide. Based on the Laplace pressure equation, the shape of a two-dimensional Cassie-Baxter droplet on a textured surface is predicted. Then the stability of the droplet is examined by considering the interference between the liquid and the surface microstructure as well as analyzing the free energy change upon the de-pinning. Afterward, the theoretical analysis is validated against the line-tension based front tracking method simulation (LTM), that seamlessly captures the attachment and detachment between the liquid and the substrate. We answer to the open debates on the sliding research field: (i) Whether the sliding initiates with the front end slip or the rear end slip, and (ii) whether the advancing and receding contact angles measured on the horizontal surface are comparable with the front and rear contact angle of the droplet at the onset of sliding. Additionally, a new droplet translation mechanism promoted by cycle of condensation and evaporation is suggested.
