Development of practical prediction model for dynamic contact angle including solid surface property

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K14590
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Fluid engineering
• Research Institution: Kumamoto University
• Principal Investigator: Yonemoto Yukihiro 熊本大学, 大学院先端科学研究部(工), 准教授 (70516418)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 動的濡れ性 / 接触角 / 臨界表面張力 / 液滴

Outline of Final Research Achievements

This study is to consider the development of the prediction model for dynamic contact angle of a droplet which includes liquid and solid physical properties. For the evaluation of the surface tension of a solid, analytical model that can evaluate the surface tension of a solid was developed. The model can be applied both hydrophilic and hydrophobic substrates. For the evaluation of the dynamic contact angle, experimental observation of a droplet impingement onto solid substrates was performed. From the results, it was revealed that the relationship between contact line velocity and the contact angle in the case of low falling height of a droplet can be predicted by one existing model. However, in the case of high falling height, there were no existing models that can predict the time variation of the contact angle of a droplet.

Free Research Field

流体工学

Academic Significance and Societal Importance of the Research Achievements

液体と固体の物性から液滴の動的接触角を予測する理論式の構築を目指した実験及び理論検討を行い、固体表面が滑らかな基板でなくとも固体の表面張力（臨界表面張力）を評価可能なモデルを構築した。また、動的濡れ性に着目した研究から、従来のモデルの適用条件が限定的であり、現象の詳細調査を含め抜本的な見直しが必要であることを明らかにした。本成果は表面物性の評価や材料評価において工学的・学術的に有用な知見である。