Journal of Energy Engineering (에너지공학)

The Korean Society for Energy (한국에너지학회)
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Effects of Humidity and Velocity on Frost Distribution Characteristics of Humid Air Flow on Cold Surfaces

차가운 표면위에서의 습공기 유동의 습도 및 속도가 착상분포 특성에 미치는 영향

  • Kwon Jeong-Tae (Department of Mechanical Engineering, Hoseo University) ;
  • Rew Keun-Ho (Department of Mechanical Engineering, Hoseo University) ;
  • Lim Hyo-Jae (Department of Mechanical Engineering, Hoseo University) ;
  • Han Ji-Won (Department of Mechanical Engineering, Hoseo University) ;
  • Kwon Young Chul (Division of Mechanical Engineering, Sunmoon University)
  • Published : 2005.12.01
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Abstract

In order to understand the heat and mass transfer characteristics of humid airflow in frosting conditions, a flat plate of aluminum with cooling modules located in the central part of the plate was used. A microscope system (resolution of 0.05 mm) was used for the measurement of local thickness of frost at seven points along the plate in the flow direction. For the total mass of frost at each test operation, an electronic balance (resolution of 1 mg) was used. The local frost thickness distributions far various test conditions were presented along with the frost mass data measured at the given operating times. The effect of humidity and velocity of humid air on frosting were analyzed.

습공기 유동의 착상조건하에서의 열 및 물질 전달 특성을 이해하기 위해서, 미니 열풍동을 제작하고 열풍동의 시험부인 사각덕트 아랫면에 알루미늄 평판을 설치하고 평판의 중심력에 전기냉각모듈(Peltier device)을 부착하였다. 현미경(해상도 0.05mm)을 이용하여 습공기 유동 방향으로 알미늄 평판위의 7개점의 서리 두께를 측정하였으며, 전자저울(해상도 1mg)을 이용하여 각 운전시간대까지의 발생된 서리의 총괄 질량을 측정하였다. 여러 가지의 실험조건에서 서리두께와 서리질량 그리고 알미늄 평판상의 온도 분포 등을 구하고, 이로부터 습공기 유동의 습도 및 속도가 서리의 성장 특성에 미치는 영향을 분석하였다.

Keywords

References

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