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

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Effect on Stratification due to Diffuser Shape in a Thermal Storage Tank

온도 성층축열조 가시화 및 실증분석에 관한 고찰

  • Lee Young-Soo (Unutilized Energy Research Center, Korea Institute of Energy Research(KIER)) ;
  • Lee Sang-Nam (Unutilized Energy Research Center, Korea Institute of Energy Research(KIER)) ;
  • Kim Jong-Ryul (Unutilized Energy Research Center, Korea Institute of Energy Research(KIER))
  • 이영수 (한국에너지 기술연구원 미활용 에너지연구센터) ;
  • 이상남 (한국에너지 기술연구원 미활용 에너지연구센터) ;
  • 김종률 (한국에너지 기술연구원 미활용 에너지연구센터)
  • Published : 2005.11.01
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Abstract

The stratified effect was investigated with three different types of diffuser shape in a thermal storage tank with variation of diffuser diameter, velocity, Froude number etc. Its effect was estimated by the degree of stratification. No matter of diffuser diameter and shape, the degree of stratification was the best as the Froude number gets closer to 1. In the case of a curved diffuser, when its diameter is a quarter of tank diameter and ejection velocity in a diffuser is approximately 0.2 m/s, the Froude number was almost 1. In the case of a flatted diffuser, when ejection velocity was 0.05 m/s, the Froude number was 1.5. Both cases which Froude number were nearer 1, showed the good degree of stratification.

Keywords

References

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