论文标题
使用分布式接触角对固体表面上的液滴的最佳控制
Optimal Control of Droplets on a Solid Surface using Distributed Contact Angles
论文作者
论文摘要
控制在固体表面上移动和固定的液滴的形状和位置是在微流体应用中经常发现的重要特征。但是，将它们自动化，例如，对于高通量应用程序，很少涉及基于模型的最佳控制策略。在这项工作中，我们演示了对倾斜表面上液滴滑动的形状和位置的最佳控制。这个基本测试用例是许多微流体设计中的基本构建块。固体表面，周围气体和液滴之间的静态接触角是控制变量的。通过使用几个控制贴片，例如，就像在电网中完成的那样，允许接触角在空间和时间上变化。在计算机实验中，我们能够使用基于梯度的优化来计算数学上最佳的接触角分布。液滴的动力学由Cahn-Hilliard-Navier-Stokes方程描述。我们预计我们的演示将成为更复杂的最佳设计和控制概念的起点。
Controlling the shape and position of moving and pinned droplets on a solid surface is an important feature often found in microfluidic applications. However, automating them, e.g., for high-throughput applications, does rarely involve model-based optimal control strategies. In this work, we demonstrate the optimal control of both the shape and position of a droplet sliding on an inclined surface. This basic test case is a fundamental building block in plenty of microfluidic designs. The static contact angle between the solid surface, the surrounding gas, and the liquid droplet serves as the control variable. By using several control patches, e.g., like done in electrowetting, the contact angles are allowed to vary in space and time. In computer experiments, we are able to calculate mathematically optimal contact angle distributions using gradient-based optimization. The dynamics of the droplet are described by the Cahn-Hilliard-Navier-Stokes equations. We anticipate our demonstration to be the starting point for more sophisticated optimal design and control concepts.
