SCI和EI收录∣中国化工学会会刊

›› 2010, Vol. 18 ›› Issue (6): 1038-1042.

• • 上一篇    

Heat Transfer and Friction Factor Studies in a Circular Tube Fitted with Twisted Tape Consisting of Wire-nails

P. Murugesan1, K. Mayilsamy2, S. Suresh3   

  1. 1. Department of Mechanical Engineering, K.S. Rangasamy College of Technology, Tiruchengode-637215, India;
    2. Department of Mechanical Engineering, Institute of Road and Transport Technology, Erode-638316, India;
    3. Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli-620015, India
  • 收稿日期:2010-06-05 修回日期:2010-10-19 出版日期:2010-12-28 发布日期:2010-12-28
  • 通讯作者: P. Murugesan, E-mail: pmksrct@gmail.com

Heat Transfer and Friction Factor Studies in a Circular Tube Fitted with Twisted Tape Consisting of Wire-nails

P. Murugesan1, K. Mayilsamy2, S. Suresh3   

  1. 1. Department of Mechanical Engineering, K.S. Rangasamy College of Technology, Tiruchengode-637215, India;
    2. Department of Mechanical Engineering, Institute of Road and Transport Technology, Erode-638316, India;
    3. Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli-620015, India
  • Received:2010-06-05 Revised:2010-10-19 Online:2010-12-28 Published:2010-12-28

摘要: This paper deals with the experimental investigation on Nusselt number,friction factor and thermal enhancement factor of a double pipe heat exchanger equipped with twisted tape consisting wire nails(WN-TT) and plain twisted tapes(P-TT) with three different twist ratios of y=2.0,4.4 and 6.0. Test runs are conducted using the water as the working fluid with Reynolds number range between 2000 and 12000 for WN-TT and P-TT. It is found that Nusselt number,friction factor and thermal enhancement factor in the tube equipped with WN-TT appreciably higher than those in the tube fitted with P-TT and plain tube. Over the range considered Nusselt number,friction factor and thermal enhancement factor in a tube with WN-TT are respectively,1.08 to 1.31,1.1 to 1.75 and 1.05 to 1.13 times of those in tube with P-TT. The better performance of WN-TT is due to combined effects of the following factors:(1) common swirling flow generated by P-TT,(2) additional turbulence offered by the wire nails. Empirical correlations for Nusselt number,friction factor and thermal enhancement factor are also formulated from the experimental results of WN-TT and P-TT.

关键词: heat transfer enhancement, friction factor, plain twisted tape, turbulence, swirl flow

Abstract: This paper deals with the experimental investigation on Nusselt number,friction factor and thermal enhancement factor of a double pipe heat exchanger equipped with twisted tape consisting wire nails(WN-TT) and plain twisted tapes(P-TT) with three different twist ratios of y=2.0,4.4 and 6.0. Test runs are conducted using the water as the working fluid with Reynolds number range between 2000 and 12000 for WN-TT and P-TT. It is found that Nusselt number,friction factor and thermal enhancement factor in the tube equipped with WN-TT appreciably higher than those in the tube fitted with P-TT and plain tube. Over the range considered Nusselt number,friction factor and thermal enhancement factor in a tube with WN-TT are respectively,1.08 to 1.31,1.1 to 1.75 and 1.05 to 1.13 times of those in tube with P-TT. The better performance of WN-TT is due to combined effects of the following factors:(1) common swirling flow generated by P-TT,(2) additional turbulence offered by the wire nails. Empirical correlations for Nusselt number,friction factor and thermal enhancement factor are also formulated from the experimental results of WN-TT and P-TT.

Key words: heat transfer enhancement, friction factor, plain twisted tape, turbulence, swirl flow