Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Interfacial Behavior of Water Droplet on Micro-Nano Structured Surfaces

마이크로-나노 구조가 있는 표면에서의 액적 계면 거동 현상에 대한 연구

  • Kwak, Ho Jae (Dept. of Mechanical Engineering, POSTECH) ;
  • Yu, Dong In (Division of Advanced Nuclear Engineering, POSTECH) ;
  • Kim, Moo Hwan (Korea Institute of Nuclear Safety(KINS)) ;
  • Park, Hyun Sun (Division of Advanced Nuclear Engineering, POSTECH) ;
  • Moriyama, Kiyofumi (Division of Advanced Nuclear Engineering, POSTECH) ;
  • Ahn, Ho Sun (Division of Mechanical System Engineering, Incheon Nat'l Univ.) ;
  • Kim, Dong Eok (Dept. of Mechanical Engineering, Kyungpook Nat'l Univ.)
  • Received : 2015.02.02
  • Accepted : 2015.03.10
  • Published : 2015.05.01
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Abstract

Recently, surfaces with micro and nano structures are the focus of various research and engineering fields to enhance wetting characteristics of the surfaces. Hydrophilic surfaces with hierarchical structures are generally characterized by the interfacial behavior of water droplets. In this study, the interfacial behavior of water droplets is experimentally investigated considering the scale of structures. Using the dry etching and conventional lithography method, quantitative hierarchical structured surfaces are developed. The behavior of the liquid-vapor interface on the test sections is visualized using an automatic goniometer and a high-speed camera. On the basis of the visualized data, the interfacial behavior of water droplets is intensively investigated according to surface geometrical characteristics.

최근 표면개질을 통한 젖음성 향상을 위하여, 마이크로와 나노 구조가 계층적(hierarchical)으로 존재하는 표면에 대한 연구가 공학 및 다양한 연구 분야에서 활발하게 진행되고 있다. 계층적구조가 존재하는 표면에서 초친수성(super-hydrophillic)은 대개 물방울(water droplet)의 계면 거동에 의해 그 특성이 확인된다. 따라서, 본 연구에서는 초친수성 표면위에서의 물방울 계면 거동에 대한 실험적 연구를 수행하였다. 포토리소그래피(photo lithography)공정과 건식 식각공정을 이용하여, 정량적으로 표면을 제작하였으며, 실험 표면에서의 계면 거동은 초고속카메라로 가시화하였다. 가시화 자료를 바탕으로, 물방울 계면거동은 표면에 존재하는 마이크로 및 나노구조의 지형학적 특성에 의해 영향을 받음을 확인하였다.

Keywords

References

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