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Measurement of turbulence intensity of cage net using the particle imaging velocimetry

입자영상유속계를 이용한 가두리 망지의 난류강도 계측

Bae, Jae-Hyun;An, Heui-Chun
배재현;안희춘

  • Received : 2014.11.11
  • Accepted : 2014.11.28
  • Published : 2014.11.30

Abstract

This study is aimed to analyze the hydrodynamic characteristics of the cage net in the circulating water channel. It visualized wake flows using a PIV (paricle imaging velocimetry) and analyzed the flow velocity distribution. In addition, the vorticity and turbulence intensity were analyzed from the wake flow distribution and compared changes by flow velocity. Results showed that the average turbulence intensity in the circulating water channel was very stable showing less than 1% in the range between 0.2 and 0.8 m/s. The drag coefficient affecting to the netting was estimated to be 1.35. The flow decreasing rate of the wake in the middle of the netting was 2.1% at the range of 0.2 m/s and it was constant at 6.6-6.9% over the range of 0.4 m/s irrespective of velocity increases. Finally, the change of turbulence intensity by netting and knot mesh could be confirmed. These results can be utilized as a basic information for the future research of flow characteristics by fishing nets and meshes.

Keywords

Cage net;PIV;Turbulence intensity

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Acknowledgement

Supported by : 국립수산과학원