Understanding droplet collision with superhydrophobic-hydrophobic–hydrophilic hybrid surfaces

Sotoudeh, F., Kamali, R., Mahmood Mousavi, S., Karimi, N. , Lee, B. J. and Khojasteh, D. (2021) Understanding droplet collision with superhydrophobic-hydrophobic–hydrophilic hybrid surfaces. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 614, 126140. (doi: 10.1016/j.colsurfa.2021.126140)

Abstract

This study uses a two-phase finite volume method to investigate the dynamics of Newtonian and non-Newtonian droplets impacting onto hybrid surfaces with various wettabilities. Six configurations with different substrate contact angles are tested ranging from hydrophilic, hydrophobic, and superhydrophilic as well as a combination of them. The temperature-dependent properties are applied to model the Newtonian droplets, and the Arrhenius law which is a relation between viscosity and shear rate is incorporated for the non-Newtonian rheology. The results show that for a hybrid surface with linear wettabilities varying from hydrophilic to hydrophobic to superhydrophobic, the maximum spreading factor is larger for both Newtonian and non-Newtonian droplets in comparison to any other surface configurations considered in this study. However, this spreading factor is minimum when a stepwise superhydrophobic-hydrophobic-hydrophilic hybrid surface is examined. Further, the residence time of Newtonian droplet has the maximum value when collides upon a hybrid surface with linear wettability distribution ranging from hydrophilic to superhydrophobic. However, the maximum value of residence time for the non-Newtonian droplet is achieved when the stepwise pattern of hydrophilic to superhydrophobic is adopted.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Karimi, Dr Nader

Creator Roles

Karimi, N.: Conceptualization, Writing – review and editing, Supervision

• Authors: Sotoudeh, F., Kamali, R., Mahmood Mousavi, S., Karimi, N., Lee, B. J., and Khojasteh, D.
• College/School: College of Science and Engineering > School of Engineering
• Journal Name: Colloids and Surfaces A: Physicochemical and Engineering Aspects
• Publisher: Elsevier
• ISSN: 0927-7757
• ISSN (Online): 1873-4359
• Published Online: 16 January 2021
• Copyright Holders: Copyright © 2021 Elsevier B.V.
• First Published: First published in Colloids and Surfaces A: Physicochemical and Engineering Aspects 614: 126140
• Publisher Policy: Reproduced in accordance with the publisher copyright policy