Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Air-Side Performance of Fin-and-Tube Heat Exchangers Having Non-Symmetric Slit Fins Under Wet Condition

비대칭형 슬릿 핀이 적용된 핀-관 열교환기의 습표면 성능

  • Kim, Nea-Hyun (Division of Mechanical System Engineering, Incheon National University)
  • 김내현 (인천대학교 기계시스템공학부)
  • Received : 2015.02.03
  • Accepted : 2015.06.11
  • Published : 2015.06.30
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Abstract

In this study, wet surface heat transfer and friction characteristics of non-symmetric slit-finned heat exchangers are experimentally investigated. Louver-finned heat exchangers are also tested for comparison purpose. The effect of fin pitch on j and f factor is negligible. Louver fin samples yield higher j and f factors than slit fin samples. For one row, j and f factors of louver fin are 27% and 31% higher than those of slit fin. For two row, j and f factors of louver fin are 15% and 30% higher. Both j and f factor decrease as the number of tube row increases. For one row, average j/f ratios of slit fin samples are 3.4% larger than those of louver fin samples. For two row, average j/f ratios of slit fin samples are 11.5% larger. A new correlation was developed using the present data.

본 연구에서는 비대칭형 슬릿 핀 열교환기의 습표면 열전달 및 압력손실에 대하여 실험적으로 검토하였다. 비교를 위하여 널리 사용되는 루버 핀 열교환기에 대한 실험도 수행하였다. 실험범위에서 핀 핏치가 j와 f 인자에 미치는 영향은 크지 않았다. 또한 루버 핀 시료의 j와 f 인자가 슬릿 핀 시료의 값들보다 크게 나타났다. 1열의 경우 평균 j 인자와 f 인자는 27%, 31% 크고, 2열에서는 15%, 30% 크게 나타났다. 슬릿 핀과 루버 핀 모두 열수가 증가하면 j와 f 인자가 감소하였다. 슬릿 핀의 평균 j/f가 루버 핀보다 1열에서 3.4%, 2열에서 11.5% 크게 나타났다. 본 데이터로부터 새로운 상관식을 도출하였다.

Keywords

References

  1. R. L. Webb and N.-H. Kim, Principles of Enhanced Heat Transfer. 2nd ed., Taylor and Francis Pub. 2005.
  2. C.-C. Wang, "On the airside performance of fin-and-tube heat exchangers," in Heat Transfer Enhancement of Heat Exchangers, Eds., S. Kakac, A.E. Bergles, F. Mayinger, H. Yuncu, Kluwer Academic Press, pp. 141-162, 1999.
  3. F. C. McQuiston, "Heat, mass and momentum transfer data for five plate-fin-tube surfaces," ASHRAE Trans., Vol. 84, Pt. 1, pp. 266-293, 1978.
  4. F. C. McQuiston, "Correlation of heat, mass and momentum transport coefficients for plate-fin-tube heat transfer surfaces with staggered tubes," ASHRAE Trans., Vol. 84, Pt. 1, pp. 294-309, 1978.
  5. C.-C. Wang, Y.-C. Hsieh and Y.-T. Lin, "Performance of plate finned tube heat exchangers under dehumidifying conditions," J. Heat Transfer, Vol. 119, pp. 109-117, 1997. DOI: http://dx.doi.org/10.1115/1.2824075
  6. Y.-T. Lin, Y.-M. Hwang and C.-C. Wang, "Performance of the herringbone wavy fin under dehumidifying conditions, Int. J. Heat Mass Trans., Vol. 45, pp. 5035-5044, 2002. DOI: http://dx.doi.org/10.1016/S0017-9310(02)00193-X
  7. C.-C. Wang and J.-S. Liaw, "Airside performance of herringbone wavy fin-and-tube heat exchangers under dehumidifying condition - Data with larger diameter tube," Vol. 55, pp. 3054-3060, 2012. DOI: http://dx.doi.org/10.1016/j.ijheatmasstransfer.2012.02.025
  8. T. Kuvannarat, C.-C. Wang and S. Wongwises, "Effect of fin thickness on the airside performance of wavy fin-and-tube heat exchangers under humidifying conditions," Int. J. Heat Mass Trans., Vol. 49, pp.2587-2596, 2006. DOI: http://dx.doi.org/10.1016/j.ijheatmasstransfer.2006.01.020
  9. C.-C. Wang and C.-T. Chang, "Heat and mass transfer for plate fin-and-tube heat exchangers, with and without hydrophilic coating," Int. J. Heat Mass Trans., Vol. 41, pp. 3109-3120, 1998. DOI: http://dx.doi.org/10.1016/S0017-9310(98)00060-X
  10. C.-C. Wang, Y.-J. Du and C.-J. Chang, "Airside performance of slit fin-and-tube heat exchangers in wet conditions," Proc. 34th National Heat Transfer Conf., NHTC'00-12092, 2000.
  11. C.-C. Wang, W.-S. Lee, W.-J. Shen and Y.-J. Chang, "Parametric study of the air-side performance of slit fin-and-tube heat exchangers in wet conditions," IMechE, Vol. 215(C), pp. 1111-1121, 2001. DOI: http://dx.doi.org/10.1243/0954406011524342
  12. C.-C. Wang, W.-S. Lee, W.-J. Sheu and Y.-J. Chang, "A comparison of the airside performance of the fin-and-tube heat exchangers in wet conditions; with and without hydrophilic coating," Applied Thermal Eng., Vol. 22, pp. 267-278, 2002. DOI: http://dx.doi.org/10.1016/S1359-4311(01)00090-4
  13. X. Ma, G. Ding, Y. Zhang and K. Wang, "Airside heat transfer and friction characteristics for enhanced fin-and-tube heat exchanger with hydrophilic coating under wet conditions", Int. J. Ref., Vol. 30, pp. 1153-1167, 2007. DOI: http://dx.doi.org/10.1016/j.ijrefrig.2007.03.001
  14. R. Yun, Y. Kim and Y. Kim, "Air side heat transfer characteristics of plate finned tube heat exchangers with slit fin configuration under wet conditions," Applied Thermal Eng., Vol. 29, pp. 3014-3020, 2009. DOI: http://dx.doi.org/10.1016/j.applthermaleng.2009.03.017
  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.,pp. 122-129, 1998.
  19. B-.B. Park, S.-M. You, B. Yoon and K.-C. Yoo, "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, Vol. 9, No. 4, pp. 454-461, 1997.
  20. T. E. Schmidt, Heat transfer calculations for extended surfaces, J. of ASRE, Refrigeration Engineering, Vol. 4, pp. 351-357, 1949.
  21. D. G. Rich, "The effect of fin spacing on the heat transfer and friction performance of multi-row, smooth plate fin-and-tube heat exchangers, ASHRAE Trans., Vol. 29, No. 2, pp. 137-145, 1973..
  22. C.-H. Min, J.-P. Cho, W.-K. Oh and N.-H. Kim, "Heat transfer and pressure drop characteristics of heat exchangers having plain fins under dry and wet conditions," Korean Journal of Air-Conditioning and Refrigeration, Vol. 16, No. 3, pp. 218-229, 2004.
  23. N.-H. Kim and H. Cho, "An Experimental investigation on the airside performance of fin-and-tube heat exchangers having silt fins," J. Enhanced Heat Transfer, under review.
  24. N.-H. Kim, K.-J. Lee and Y. B. Jeong, "Airside performance of oval tube heat exchangers having sine wave fins under wet condition," Applied Thermal Eng. Vol. 66, pp. 580-589, 2014. DOI: http://dx.doi.org/10.1016/j.applthermaleng.2014.02.042
  25. C.-C. Wang, Y.-T. Lin and C.-J. Lee, "Heat and momentum transfer for compact louvered fin-and-tube heat exchangers in wet conditions," Int. J. Heat MAss Transfer, Vol. 43, pp. 3443-3452. DOI: http://dx.doi.org/10.1016/S0017-9310(99)00375-0