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

The Korean Society of Mechanical Engineers (대한기계학회)
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Velocity Field Measurements of a Vertical Turbulent Buoyant Jet Using a PIV Technique

PIV 기법을 이용한 비등온 부력제트의 유동구조에 관한 연구

  • 신대식 (삼성전자, 가전정보총괄 냉공조사업부) ;
  • 윤정환 (포항공과대학교 대학원 기계공학과) ;
  • 이상준
  • Published : 2001.05.01
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Abstract

The flow characteristics of a turbulent buoyant jet were experimentally investigated using a single-frame PIV system. The Reynolds number based on the nozzle exit velocity and nozzle diameter was about Re=5$\times$10$^3$. The instantaneous velocity fields in the streamwise plane passing the jet axis were measured in the near field X/D <11 with and without the temperature gradient. By ensemble averaging the instantaneous velocity fields, the spatial distributions of mean velocity, vorticity, and higher-order statistics up to third order were obtained. The temperature difference of 10$\^{C}$ does not affect a significant influence to the flow structure in the near field, but the total entrainment rate is increased slightly. The entrainment rate shows a linear variation with the streamwise distance in the region after X/D=5.0.

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References

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