SCI和EI收录∣中国化工学会会刊

›› 2015, Vol. 23 ›› Issue (3): 490-498.DOI: 10.1016/j.cjche.2014.05.018

• 流体力学与传递现象 • 上一篇    下一篇

Enhanced heat transfer in a heat exchanger square-duct with discrete V-finned tape inserts

Watcharin Noothong, Supattarachai Suwannapan, Chinaruk Thianpong, Pongjet Promvonge   

  1. Department of Mechanical Engineering, Faculty of Engineering, King Mongkut's Institute of Technology Ladkrabang, Bangkok 10520, Thailand
  • 收稿日期:2013-12-07 修回日期:2014-05-22 出版日期:2015-03-28 发布日期:2015-04-03
  • 通讯作者: Pongjet Promvonge
  • 基金资助:
    Supported by the Energy Policy and Planning Office, Ministry of Energy, Thailand.

Enhanced heat transfer in a heat exchanger square-duct with discrete V-finned tape inserts

Watcharin Noothong, Supattarachai Suwannapan, Chinaruk Thianpong, Pongjet Promvonge   

  1. Department of Mechanical Engineering, Faculty of Engineering, King Mongkut's Institute of Technology Ladkrabang, Bangkok 10520, Thailand
  • Received:2013-12-07 Revised:2014-05-22 Online:2015-03-28 Published:2015-04-03
  • Supported by:
    Supported by the Energy Policy and Planning Office, Ministry of Energy, Thailand.

摘要: The article presents an experimental and numerical study on thermal performance enhancement in a constant heatfluxed square-duct inserted diagonallywith 45°discrete V-finned tapes (DFT). The experimentswere carried out by varying the airflow rate through the tested square duct with DFT inserts for Reynolds number from 4000 to 25000. The effect of the DFT with V-tip pointing upstream at various relative fin heights and pitches on heat transfer and pressure drop characteristics was experimentally investigated. Both the heat transfer and pressure drop were presented in terms of Nusselt number and friction factor respectively. Several V-finned tape characteristics were introduced such as fin-to duct-height ratio or blockage ratio (RB=e/H=0.075, 0.1, 0.15 and 0.2), fin pitch to duct height ratio (RP=P/H=0.5, 1.0, 1.5 and 2.0) and fin attack angle, α=45°. The experimental results reveal that the heat transfer and friction factor values with DFT inserts increase with the increment of RB but the decrease of RP. The inserted square-duct at RB=0.2 and RP=0.5 provides the highest heat transfer and friction factor while the one with RB=0.1 and RP=1.5 yields the highest thermal performance. Also, a numerical simulation was conducted to investigate the flow structure and heat transfer mechanism inside the tested duct with DFT inserts.

关键词: Heat exchanger, Square duct, Discrete V-fins, Thermal enhancement, Friction factor

Abstract: The article presents an experimental and numerical study on thermal performance enhancement in a constant heatfluxed square-duct inserted diagonallywith 45°discrete V-finned tapes (DFT). The experimentswere carried out by varying the airflow rate through the tested square duct with DFT inserts for Reynolds number from 4000 to 25000. The effect of the DFT with V-tip pointing upstream at various relative fin heights and pitches on heat transfer and pressure drop characteristics was experimentally investigated. Both the heat transfer and pressure drop were presented in terms of Nusselt number and friction factor respectively. Several V-finned tape characteristics were introduced such as fin-to duct-height ratio or blockage ratio (RB=e/H=0.075, 0.1, 0.15 and 0.2), fin pitch to duct height ratio (RP=P/H=0.5, 1.0, 1.5 and 2.0) and fin attack angle, α=45°. The experimental results reveal that the heat transfer and friction factor values with DFT inserts increase with the increment of RB but the decrease of RP. The inserted square-duct at RB=0.2 and RP=0.5 provides the highest heat transfer and friction factor while the one with RB=0.1 and RP=1.5 yields the highest thermal performance. Also, a numerical simulation was conducted to investigate the flow structure and heat transfer mechanism inside the tested duct with DFT inserts.

Key words: Heat exchanger, Square duct, Discrete V-fins, Thermal enhancement, Friction factor