Journal of Power System Engineering (동력기계공학회지)

The Korean Society for Power System Engineering (한국동력기계공학회)
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Effect of Rib Height on Turbulence and Convective Heat Transfer

리브의 높이가 난류 및 열전달특성에 미치는 영향

  • Nine, Md.J. (Department of Energy & Mechanical Engineering, GyeongSang National University) ;
  • Kim, S.J. (Department of Energy & Mechanical Engineering, GyeongSang National University) ;
  • Jeong, H.M. (Institute of Marine Industry, GyeongSang National University) ;
  • Chung, H.S. (Institute of Marine Industry, GyeongSang National University) ;
  • Rahman, M.Sq. (Dept. of Agricultural & Industrial Engineering, Hajee Mohammad Danesh Science & Technology University)
  • 나인 (경상대학교 정밀기계공학과) ;
  • 김수진 (경상대학교 정밀기계공학과) ;
  • 정효민 (경상대학교 정밀기계공학과, 해양산업연구소) ;
  • 정한식 (경상대학교 정밀기계공학과, 해양산업연구소) ;
  • 라흐만
  • Received : 2012.10.18
  • Accepted : 2012.12.07
  • Published : 2012.12.31
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Abstract

Effect of rib heights is found as significant parameter to enhance convective heat transfer performance under laminar and low turbulent regime. Circular ribs with different ribheight to channel height ratios, e/H = 0.05, 0.1, 0.15, are fabricated over the copper substrate respectively in a rectangular duct having 7.5 cross sectional aspect ratio. Only one rib pitch to rib height ratio (P/e = 10) has been chosen for all different height ribs. The result shows that the arithmetic average of turbulence intensity decreases with decreasing roughness height calculated between two ribs under laminar and low turbulent region. It occurs because the area of recirculation and reattachment zone also decreases with decreasing rib height. Optimum thermal enhancement factor is derived by 0.1 rib height to channel height ratio under low turbulent region but 0.15 rib height to channel height ratio gives maximum subjected to laminar flow.

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References

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