Numerical Simulation of Droplet Impacting on Different Rib Surfaces
摘要
Droplet impact on a ribbed surface finds broad applications in both natural and industrial settings. This study aims to investigate the fundamental physics governing droplet dynamics upon impact with ribbed surfaces. Three types of rib surfaces—square, truncated cone, and discrete cylindrical ribs—were used to examine the effect of rib surfaces on the post-impact dynamics of a spherical droplet. The numerical simulations were performed on a finite volume solver in ANSYS FLUENT software, employing the Volume-of-Fluid (VOF) method at specific Weber number ( \(We\) ) of 5 and Reynolds number ( \(Re\) ) of 875 numbers based on the droplet properties. The simulation tracks the time-dependent evolution of the droplet spreading factor (the ratio of instantaneous diameter to the initial droplet diameter). The study demonstrates a notable reduction (~29.5%) in contact time for the droplet impacting on the truncated cone rib surface, whereas no significant improvement was observed with cylindrical ribs compared to the standard square rib case. Additionally, the dynamics of droplets over different rib geometries were analyzed, including the Wenzel and Cassie–Baxter states, highlighting the role of a rib surface on droplet dynamics at constant Weber and Reynolds number conditions. The present work explores the possibility to enhancing the efficiency and effectiveness of surfaces used in self-cleaning, anti-corrosion, anti-icing, and heat transfer applications.