Multi-phase Flow Velocity Measurement Technique using Shadow Graphic Images

다위상 유체 속도 계측을 위한 영상기법 적용

  • Ryu, Yong-Uk (R&D center, Hyundai Engineering and Construction Co. Ltd.) ;
  • Jung, Kwang-Hyo (Dept. of Naval Architecture and Ocean Engineering, Dong-Eui University)
  • 류용욱 (현대건설(주) 연구개발본부) ;
  • 정광효 (동의대학교 조선해양공학과)
  • Received : 2012.06.11
  • Accepted : 2012.06.19
  • Published : 2012.06.30


Air-water flow measurements are of importance for the coastal and ocean engineering fields. Although kinematic investigations of the multi-phase flows have been conducted for long time, velocity measurements still are concerned with many researchers and engineers in coastal and ocean areas. In the present study, an imaging technique using shadowgraphy and fiber optic probe for velocity measurements of air bubbles is introduced. The shadow graphy image technique is modified from the typical image velocimetry methods, and optical fibers are used for the well-known intrusive coupled phase-detection probe system. Since the imaging technique is a non-intrusive optical method from the air, it is usually applied for 2D flows. On the other hand, the double fiber optic probes touch flows regardless of flow patterns. The results of the flow measurements by both methods are compared and discussed. The methods are also applied to the measurements of overtopping flows by a breaking wave over the structure fixed on the free surface.


Supported by : 한국학술진흥재단(또는 한국과학재단)


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