Journal of the Korean Society of Visualization (한국가시화정보학회지)

The Korean Society of Visualization (한국가시화정보학회)
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Experimental study of spreading phenomena on hydrophilic micro-textured surfaces depending on surface geometrical features

친수성 마이크로 기둥 구조 표면에서의 표면 지형적 특성에 따른 퍼짐성 현상에 대한 실험적 연구

  • Jang, Munyoung (Department of Mechanical Design Engineering, Pukyong National University) ;
  • Park, Sehyeon (Department of Mechanical Design Engineering, Pukyong National University) ;
  • Yu, Dong In (Department of Mechanical Design Engineering, Pukyong National University)
  • Received : 2018.12.03
  • Accepted : 2018.12.27
  • Published : 2018.12.31
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Abstract

In multiphase systems, surface wettability is one of dominant design parameters to enhance system performance. Since surface wettability can be maximized and minimized with micro-textured surfaces, therefore micro-textured surfaces are widely countered in various research and engineering fields. In this study, for better understanding of micrometer scaled surface wettability, spreading phenomena is experimentally investigated on the hydrophilic micro-textured surfaces. By photolithography and conventional dry etching method, there are prepared the surfaces with uniformly arrayed micro-pillars. The interfacial motions of a water droplet on the test sections are visualized by high speed camera in top view. On the basis of visualization data, it is analyzed the relation between dynamic coefficient and geometrical features on micro-textured surfaces.

Keywords

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Fig. 1. Test sections (a) MEMS recipe, (b) 3D-profiler image (d20g20 case)

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Fig. 2. Visualization of spreading phenomena (d4g4 case)

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Fig. 3. Comparison of precursor radius in various geometrical conditions (total regimes)

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Fig. 4. Comparison of precursor radius in various geometrical conditions (2nd regime)

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Fig. 5. Dynamic coefficient (D) depending on roughness ratio (fW)

Table 1. Specific geometrical features of test sections

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