Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Study on Single-Phase Thermal and Hydrodynamic Characteristics in the Entry Region of a Mini-Channel Heat Sink

히트싱크 미세채널 내의 입구유동 영역에서의 단상 열유동 특성에 관한 연구

  • Jang, Yong-Hee (Department of Mechanical Engineering, Graduate School of Korea University) ;
  • Kim, Yong-Chan (Department of Mechanical Engineering, Korea University) ;
  • Lee, Kyu-Jeong (Department of Mechanical Engineering, Korea University)
  • 장용희 (고려대학교 대학원 기계공학과) ;
  • 김용찬 (고려대학교 기계공학과) ;
  • 이규정 (고려대학교 기계공학과)
  • Published : 2006.12.10
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Abstract

Although the advance in electronic technology enables a large number of circuity to be packed in a small volume, it is simultaneously required to remove the high heat load produced by them. In this study, the heat transfer and pressure drop characteristics of a mini-channel heat exchanger, which is designed for liquid cooling of electronic components, are investigated by varying operating conditions. Water and FC-72 were used as working fluids. The mini-channel heat exchanger was made with circular shape channels having din-meters of 2, 3, and 4 mm in regular intervals, and the channel length was 100 mm. The header and inlet guide pathway to provide uniform inflow were attached at the inlet of the test section. Copper block including the heaters was attached at the sidewall of the test section as a heat source, which provided the heat flux from 5 to $15W/cm^2$. The entrance effects enhanced the heat transfer coefficient in the mini-channel significantly. In addition, the single-phase pressure drop in the mini-channel was very similar to that predicted by the laminar flow correlation except that the transition Re decreased due to flow instability in the entrance region.

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References

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