Predicting the drop size passing through a superhydrophobic orifice

Jereb, Samo (author), Zupančič, Matevž (author), Može, Matic (author), Golobič, Iztok (author)

Superhydrophobic surfaces can be utilized in various applications, such as enhanced heat transfer, anti-icing, self-cleaning, and viscous drag reduction. In this work, we investigated the water droplet size separation using superhydrophobic surfaces, which is relatively new and unexplored research field, but yet promising for pharmaceutical and medical applications. We developed a theoretical model for predicting the diameter of a droplet passing through a smaller superhydrophobic orifice by considering the balance of forces, geometrical characteristics, and the surface wettability. For verification of the model, experimental water droplet size separation was conducted using a thin superhydrophobic copper foil with a laser-cut orifice with a diameter ranging from 1.2 to 2.1 mm. A comparison of the experimental and analytical results has shown that the error of the model is less than 20% within the model's validity range with the upper limit at the capillary length of the fluid. By moving away from this limit toward smaller droplet diameters, the accuracy of the model improves and reaches an error of less than 7% at the smallest used orifice diameter of 1.2 mm.

• Language: English
• Keywords: superhydrophobic surface, droplet size separation, theoretical model, orifice
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Publication date: 11.11.2022
• Year: 2022
• Number of pages: 8 str.
• Numbering: Vol. 34, iss. 11, art. 117117
• PID: 20.500.12556/RUL-142598
• UDC: 66.02
• ISSN on article: 1089-7666
• DOI: 10.1063/5.0125906
• COBISS.SI-ID: 129336579
• Publication date in RUL: 15.11.2022

Record is a part of a journal

• Title: Physics of fluids
• Shortened title: Phys. fluids
• Publisher: American Institute of Physics
• ISSN: 1089-7666
• COBISS.SI-ID: 18986023

Secondary language

• Language: Slovenian
• Keywords: superhidrofobna površina, velikostna separacija kapljic, teoretični model, odprtina