DOI QR코드

DOI QR Code

Airside Performance of Fin-and-Tube Heat Exchangers Having Round Wave Fins

둥근 웨이브 핀-관 열교환기의 공기 측 전열 성능

  • Received : 2015.03.19
  • Accepted : 2015.08.20
  • Published : 2015.12.31

Abstract

In this study, airside performance of round fin-and-tube heat exchangers are compared with that of the herringbone wave fin-and-tube heat exchangers with an aim to investigate the effect of fin shape on thermal performance. Results show that j factors of the round wave fin are 1.2~22% larger than those of herringbone wave fin. The f factors of the round wave fin are -1.0~29% smaller than those of herringbone wave fin for 1 or 2 row configuration. For 3 row configuration, f factors of the round wave fin are 8.3~23% larger. The reason may be attributed to the reduced recirculation zone in the valley of the fin for round wave fin as compared with that of the herringbone wave fin. For round wave fin, the effect of fin pitch on j and f factor is not significant. In addition, j factors decrease as the number of tube row increases. On the other hand, f factors are independent of the number of tube row. A new correlation was developed based on the present data.

Keywords

Wave fin;Fin-and-tube heat exchanger;Heat transfer Coefficient;Pressure drop

References

  1. Webb RL, Kim NH, Principles of Enhanced Heat Transfer. Taylor and Francis Pub., 2nd ed., 1994.
  2. Wang CC, On the airside performance of fin-andtube heat exchangers, in Heat Transfer Enhancement of Heat Exchangers. S. Kakac et al. (Eds.), Kluwer Academic Press, 1999, 141-162.
  3. Goldstein L, Sparrow EM, Experiments on the transfer characteristics of a corrugated fin and tube heat exchanger configuration, J. Heat Transfer, 1976, 98, 26-34. https://doi.org/10.1115/1.3450464
  4. Ali MM, Ramadhyani S, Experiments on convective heat transfer in corrugated channels, Experimental Heat Transfer, 1992, 5, 175-193. https://doi.org/10.1080/08916159208946440
  5. Kim NH, Yun JH, Webb RL, Heat transfer and friction correlations for wavy plate fin-and-tube heat exchangers, J. Heat Transfer, 1997, 119, 560-567. https://doi.org/10.1115/1.2824141
  6. Beecher DT, Fagan TJ, Effects of fin pattern on the air-side heat transfer coefficients in plate finned tube heat exchangers, ASHRAE Trans., 1987, 93(2) 1961-1984.
  7. Wang CC, Fu WL, Chang CT, Heat transfer and friction characteristics of typical wavy fin-and-tube heat exchangers, Exp. Thermal Fluid Science, 1997, 14, 174-186. https://doi.org/10.1016/S0894-1777(96)00056-8
  8. Wang CC, Tsai YM, Lu DC, Comprehensive study of convex louver and wavy fin-and-tube heat exchangers, J. Thermophysics Heat Transfer, 1998, 12(3), 423-430. https://doi.org/10.2514/2.6354
  9. Wang CC, Lin YT, Lee CJ, Chang YJ, Investigation of wavy fin-and-tube heat exchangers: A contribution to databank, Experimental Heat Transfer, 1999, 12, 73-89. https://doi.org/10.1080/089161599269825
  10. Wang CC, Chang YJ, Chiou NF, Effects of waffle height on the air-side performance of wavy fin-and-tube heat exchangers, Heat Transfer Engineering, 1999, 20(3), 45-56.
  11. Webb RL, Air-side heat transfer correlations for flat and wavy plate fin-and-tube geometries, ASHRAE Trans., 1990, 96(2), 445-449.
  12. Wang CC, Jang JY, Chiou NF, A heat transfer and friction correlation for wavy fin-and-tube heat exchangers, Int. J. Heat Mass Trans., 1999, 42, 1919-1924. https://doi.org/10.1016/S0017-9310(98)00288-9
  13. Mirth DR, Ramadhyani S, Correlations for predicting the air-side Nusselt numbers and friction factors in chilled water cooling coils, Experimental Heat Transfer, 1994, 7, 143-162. https://doi.org/10.1080/08916159408946477
  14. Kang HC, Webb RL, Evaluation of the wavy fin geometry used in air-cooled finned-tube heat exchangers, Proceedings of 11th International Heat Transfer Conference, Aug. 23-28, Kyoungju, Korea, 1998, 6, 95-100.
  15. ASHRAE Standard 41.1, Standard method for temperature measurement, ASHRAE, 1986.
  16. ASHRAE Standard 41.2, Standard method for laboratory air-flow measurement, ASHRAE, 1987.
  17. ASHRAE Standard 41.5, Standard measurement guide, engineering analysis of experimental data, ASHRAE, 1975.
  18. ESDU 98005, Design and performance evaluation of heat exchangers: the effectiveness and NTU method, Engineering and Sciences Data Unit 98005 with Amendment A, London ESDU International plc., 1998, 122-129.
  19. Park BB, You SM, Youn B, Yoo KC, Experimental study of heat transfer and pressure drop characteristics for flow of water inside circular smooth and micro-fin tubes, Korean J. Air Conditioning Refrigeration, 1997, 9(4), 454-461.
  20. Gnielinski V, New equation for heat and mass transfer in turbulent pipe and channel flow, Int. Chem. Eng., 1976, 16, 359-368.
  21. Schmidt TE, Heat transfer calculations for extended surfaces, J of ASRE, Refrigeration Engineering, 1949, 4, 351-357.
  22. Ramadhyani S, Numerical prediction of flow and heat transfer in corrugated ducts, ASME, HTD-Vol. 66, 1986, 37-43.
  23. Torikoshi K, Xi. GN, Nakazawa Y, Asano H, Flow and heat transfer performance of a plate fin and tube heat exchanger (first report: effect of fin pitch), Heat Transfer 1994, Proceedings of the 10th Int. Heat Transfer Conf., 1994, 4, 411-416.
  24. Jang JY, Chen LK, Numerical analysis of heat transfer and fluid flow in a three-dimensional wavy fin-and-tube heat exchanger, Int. J. Heat Mass Transfer, 1997, 40(16), 3981-3990 https://doi.org/10.1016/S0017-9310(97)00047-1
  25. Min CK, Cho JP, Oh WK and Kim NH, Heat transfer and pressure drop characteristics of heat exchangers having plain fins under dry and wet conditions, Korean J. Air-Conditioning and Refrigeration, 2004, 16(3), 218-229.
  26. Wang CC, Lee WS, Sheu WJ, A comparative study of compact enhanced fin-and-tube heat exchangers, Int. J. Heat Mass Transfer, 2001, 44, 3565-3573. https://doi.org/10.1016/S0017-9310(01)00011-4
  27. Rich DG, The effect of fin spacing on the heat transfer and friction performance of multi-row, smooth plate fin-and-tube heat exchangers, ASHRAE Trans., 1973, 72(2) 137-145.