Design and droplet motion simulation of wettability-patterned surface for droplet control

Droplet control technology has broad application prospects and the wettability-patterned surface is a popular way to realize it. However, as an aided means of experiment, simulation is seldom found in the relevant researches. In this paper, a wettability-patterned surface with radial tree-shape pattern is designed firstly and the droplet motions at different positions on it are simulated according to the model settings proposed. Subsequently, four new wedge-shaped derivative patterns, that is mesh pattern, unidirectional tree-shape pattern, radial arc-shape pattern, and dragon pattern, are designed to investigate the droplet motions on the wettability-patterned surfaces with different paths. Finally, a novel vapor chamber model with mesh patterned condenser and radial tree-shape patterned evaporator is developed as an application expansion of the two-dimensional (2D) patterns for special 3D droplet control scenario, and the working medium droplet motions in it are investigated similarly. The simulation result indicates that the conceptual vapor chamber model developed in this paper is feasible, which can leave out the wicks and accelerate the working medium circulation.