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Multi-phase Flow Velocity Measurement Technique using Shadow Graphic Images

다위상 유체 속도 계측을 위한 영상기법 적용

  • Received : 2012.06.11
  • Accepted : 2012.06.19
  • Published : 2012.06.30

Abstract

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.

Keywords

Multi-phase flows;Bubble image velocimetry;Shadow graphy image technique;Fiber optic reflectometer;Overtopping flows

References

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Cited by

  1. Application of Image Technique and Optical Fiber Sensor for Air-water Mixture Flow vol.48, pp.7, 2015, https://doi.org/10.3741/JKWRA.2015.48.7.535
  2. Experimental Study on Behavior of Green Water for Rectangular Structure vol.30, pp.1, 2016, https://doi.org/10.5574/KSOE.2016.30.1.044
  3. Experimental Study on Variations in Behavior of Green Water and Flow Kinematics on Deck with Various Flare Angles vol.32, pp.2, 2018, https://doi.org/10.26748/KSOE.2018.4.32.2.077

Acknowledgement

Supported by : 한국학술진흥재단(또는 한국과학재단)