JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE) ›› 2015, Vol. 45 ›› Issue (2): 56-61.doi: 10.6040/j.issn.1672-3961.0.2014.272

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Model of contact angle of hydrophobic surface based on minimum Gibbs free energy

SONG Hao, LIU Zhanqiang, SHI Zhenyu, CAI Yukui   

  1. Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education, School of Mechanical Engineering, Shandong University, Jinan 250061, Shandong, China
  • Received:2014-09-24 Revised:2015-01-20 Online:2015-04-20 Published:2014-09-24

Abstract: Based on the function of Young used for smooth surface and the model of Cassie-Baxter used for rough surface, the prediction model for contact angle of hydrophobic surface based on minimum Gibbs free energy was proposed. The model for contact angle prediction was then modified by considering the influence of skew walls on the contact line between gas-liquid. The effects of hydrophobic surface material properties and geometric parameters on contact angle were analyzed based on the modified model. The results showed that, under the same condition of machined micro-surface, the contract angle on the hydrophobic surface root was larger than that on the hydrophilic one. Besides, for the Cassie-Baxter model, the larger radio between the width of groove and the width of convex was, the larger contract angle was.

Key words: contact line, hydrophobic, energy method, contact angle, skew wall

CLC Number: 

  • TG174.4
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