论文标题
控制光滑化学模式的液滴蒸发
Control of droplet evaporation on smooth chemical patterns
论文作者
论文摘要
我们研究了固体表面上二维液滴的蒸发。固体是平坦的，但具有光滑的化学变化，导致依赖于空间的局部接触角。随着液滴的变化，我们对液滴的平衡性能进行了详细的分叉分析，观察到分叉的层次结构的出现在很大程度上取决于特定的潜在化学模式。对称和周期性模式导致一系列干草叉和鞍节分叉，使稳定的溶液成为鞍节点。在动态条件下，这种变化的不稳定性表明，系统中的任何扰动都可以使液滴横向移动，同时放松到最近的稳定点，正如Cahn-Hilliard和Navier-Stokes方程系统的数值计算所证实的那样。我们还考虑具有振幅梯度的模式，该模式在解决方案空间中创建一组断开的稳定分支，从而导致蒸发后液滴的位置不断变化。
We investigate the evaporation of a two-dimensional droplet on a solid surface. The solid is flat but with smooth chemical variations that lead to a space-dependent local contact angle. We perform a detailed bifurcation analysis of the equilibrium properties of the droplet as its size is changed, observing the emergence of a hierarchy of bifurcations that strongly depends on the particular underlying chemical pattern. Symmetric and periodic patterns lead to a sequence of pitchfork and saddle-node bifurcations that make stable solutions to become saddle nodes. Under dynamic conditions, this change instability suggests that any perturbation in the system can make the droplet to shift laterally while relaxing to the nearest stable point, as is confirmed by numerical computations of the Cahn-Hilliard and Navier-Stokes system of equations. We also consider patterns with an amplitude gradient that creates a set of disconnected stable branches in the solution space, leading to a continuous change of the droplet's location upon evaporation.
