SCI和EI收录∣中国化工学会会刊

›› 2011, Vol. 19 ›› Issue (3): 410-423.

• FLUID FLOW AND TRANSPORT PHENOMENA • Previous Articles     Next Articles

Influence of Double-sided Delta-wing Tape Insert with Alternate-axes on Flow and Heat Transfer Characteristics in a Heat Exchanger Tube

Smith Eiamsa-ard1, Pongjet Promvonge2   

  1. 1. Department of Mechanical Engineering, Faculty of Engineering Mahanakorn University of Technology, Bangkok 10530, Thailand;
    2. Faculty of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bankok 10520, Thailand
  • Received:2010-12-20 Revised:2011-03-20 Online:2011-06-28 Published:2011-06-28
  • Supported by:
    Supported by the Thailand Research Fund(TRF),Office of Higher Education Commission and Mahanakorn University of Technology

Influence of Double-sided Delta-wing Tape Insert with Alternate-axes on Flow and Heat Transfer Characteristics in a Heat Exchanger Tube

Smith Eiamsa-ard1, Pongjet Promvonge2   

  1. 1. Department of Mechanical Engineering, Faculty of Engineering Mahanakorn University of Technology, Bangkok 10530, Thailand;
    2. Faculty of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bankok 10520, Thailand
  • 通讯作者: Smith Eiamsa-ard, E-mail: smith@mut.ac.th
  • 基金资助:
    Supported by the Thailand Research Fund(TRF),Office of Higher Education Commission and Mahanakorn University of Technology

Abstract: The convective heat transfer and friction behaviors of turbulent tube flow through a straight tape with double-sided delta wings(T-W)have been studied experimentally.In the current work,the T-W formed on the tape was used as vortex generators for enhancing the heat transfer coefficient by breakdown of thermal boundary layer and by mixing of fluid flow in tubes.The T-W characteristics are(1)T-W with forward/backward-wing arrangement,(2)T-W with alternate axis(T-WA),(3)three wing-width ratios and(4)wing-pitch ratios.The experimental result reveals that for using the T-W,the increases in the mean Nusselt number(Nu)and friction factor are,respectively,up to 165% and 14.8 times of the plain tube and the maximum thermal performance factor is 1.19.It is also obvious that the T-W with forward-wing gives higher heat transfer rate than one with backward-wing around 7%. The present investigation also shows that the heat transfer rate and friction factor obtained from the T-WA is higher than that from the T-W.In addition,the flow pattern and temperature fields in the T-W tube with both backward and forward wings were also examined numerically.

Key words: fluid flow, heat transfer, tape with centre-wing, wing, alternate axis, vortex

摘要: The convective heat transfer and friction behaviors of turbulent tube flow through a straight tape with double-sided delta wings(T-W)have been studied experimentally.In the current work,the T-W formed on the tape was used as vortex generators for enhancing the heat transfer coefficient by breakdown of thermal boundary layer and by mixing of fluid flow in tubes.The T-W characteristics are(1)T-W with forward/backward-wing arrangement,(2)T-W with alternate axis(T-WA),(3)three wing-width ratios and(4)wing-pitch ratios.The experimental result reveals that for using the T-W,the increases in the mean Nusselt number(Nu)and friction factor are,respectively,up to 165% and 14.8 times of the plain tube and the maximum thermal performance factor is 1.19.It is also obvious that the T-W with forward-wing gives higher heat transfer rate than one with backward-wing around 7%. The present investigation also shows that the heat transfer rate and friction factor obtained from the T-WA is higher than that from the T-W.In addition,the flow pattern and temperature fields in the T-W tube with both backward and forward wings were also examined numerically.

关键词: fluid flow, heat transfer, tape with centre-wing, wing, alternate axis, vortex