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 of a Variation of a Main Duct Area on Flow Distribution of Each Branch

주덕트의 단면적 변화가 분지덕트의 유량분배에 미치는 영향

  • Lee Jai-Ho (Graduate School of Mech Eng., Chonbuk National Univ.) ;
  • Kim Beom-Jun (Graduate School of Mech Eng., Chonbuk National Univ.) ;
  • Cho Dae-Jin (Graduate School of Mech Eng., Chonbuk National Univ.) ;
  • Yoon Suck-Ju (Dept. of Mech Eng., Automobile Hi-Technology Research Center, Chonbuk National Univ.)
  • 이재호 (전북대학교 기계공학과 대학원) ;
  • 김범준 (전북대학교 기계공학과 대학원) ;
  • 조대진 (전북대학교 기계공학과 대학원) ;
  • 윤석주 (전북대학교 기계공학과 자동차 신기술연구소)
  • Published : 2005.04.01
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Abstract

With the development of a living standard, the importance of indoor air conditioning system in all kinds of buildings and vehicles has increased. A lot of researches on energy losses in a duct and various kinds of flow pattern in branches or junctions have been carried out over many years, because the primary object of a duct system used in HVAC is to provide equal flow rate in the interior of each room by minimizing pressure drop. In this study, to get equal flow distribution in each branch, a blockage is applied to the rectangular duct system. The flow analysis for flow distribution of a rectangular duct with two branches was performed by CFD. By using SIMPLE algorithm and finite volume method, flow analysis is performed in the case of 3-D, incompressible, turbulent flow. Also, the standard $k-{\varepsilon}$ model and wall function method were used for analysis of turbulent fluid flow. The distribution diagrams of static pressure, velocity vector, turbulent energy and kinetic energy in accordance with variation of Reynolds number and blockages location in a rectangular duct show that flow distribution at duct outlets is improved by a blockage. In this rectangular duct system, mean velocity and flow rate distribution in two branch outlets are nearly constant regardless of variation of Reynolds number, and a flow pattern of the internal duct has a same tendency as well.

Keywords

References

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