Numerical evaluation of thermo hydraulic performance index of a double pipe heat exchanger using double sided louvered winglet tape
1Department of Mechanical Engineering, VTU Belgaum, 590018, India
2Department of Mechanical Engineering, BGSIT-Adichunchanagiri University, BG Nagara, 571448, India
3Department of Mechanical and Manufacturing Engineering, MS Ramaiah University of Applied Sciences, Bangalore, Karnataka 560054, India
J Ther Eng 2020; 6(5): 843-857 DOI: 10.18186/thermal.800267
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Abstract

The decade has witnessed great importance of numerical techniques for scientists and researchers in deciding the correctness, stability, and reliability of new designs. In the present study a numerical technique has been implemented to investigate the thermo hydraulic performance of the Louvered winglet tape inside the tube section of the double pipe heat exchanger. The Louvered winglet tape has been examined with the slope angle of 50, 100, 150 and 210 to study their thermal characte ristics. The Reynolds number 4000 30000 was examined on slope angle of 50, 100, 150 and 210 to study their flow characteristics in the turbulent domain. A smooth pipe was examined to evaluate heat transfer characteristics in terms of Nusselt number and fri ction coefficient over augmented tube with Louvered winglet tape. The results show a satisfactory performance of Louvered winglet tape over the smooth tube with a similar trend of friction factor, Nusselt number, and thermo hydraulic performance index (THP I). The percentage of increment of the Nusselt number of the results is found to be 237.04%, 258.4%, 275.11%, and 289.72% when compared to smooth pipe with respect to slope angle of 50, 100, 150 and 210, respectively. The amount of increase in the friction factor in comparison with plain tube is 5.13, 6.73, 8.33, and 11.73 times of that of smooth pipe with respect to slope angle of 50, 100, 150 and 210, respectively. The Louvered winglet tape with slope angle 150 has shown to be promising with respect to hi gher THPI when considering with other slope angle of 50, 100, and 210. The maximum THPI of 1.85 was obtained for slope angle 150 at Re 12000. Similarly, the THPI values for other slope angle 50, 100, and 210 are 1.71, 1.78 and 1.69. In addition to better p erformance the Louvered winglet tape can be easily fabricated and adapted for a wide variety of heat transfer industries.