경사지게 설치된 평행류형 알루미늄 열교환기의 공기측 전열 성능

Air-side Performance of Aluminum Heat Exchangers at Different Inclination Angles

  • 발행 : 2008.03.10

초록

The effect of inclination angle on the heat transfer and pressure drop characteristics of the brazed aluminum heat exchangers is experimentally investigated. Three samples having different fin pitches(1.25, 1.5 and 2.0 mm) were tested. Results show that heat transfer coefficient is not affected by the inclination angle. However, the friction factor increases as the inclination angle increases with negligible difference between the forward and backward inclination. Both the heat transfer coefficient and the friction factor are the smallest at $F_p=1.5mm$, followed by $F_p=2.0mm$ and 1.25mm. Possible explanation is provided considering the louver layout. Comparison with existing correlations is also made.

키워드

참고문헌

  1. Webb, R. L. and Jung, S. H., 1992, Air-side performance of enhanced brazed aluminum heat exchangers, ASHRAE Trans., Vol. 98, No. 2, pp. 391-410
  2. Webb, R. L. and Lee, H., 2001, Brazed aluminum heat exchangers for residential air-conditioning, J. Enhanced Heat Transfer, Vol. 8 pp. 1-14 https://doi.org/10.1615/JEnhHeatTransf.v8.i1.10
  3. Davenport, C. J., 1980, Heat transfer and fluid flow in louvered triangular ducts, Ph.D thesis, Lanchester Polytechnic, U. K.
  4. Davenport, C. J., 1983, Correlation of heat transfer and flow friction characteristics of louvered fin, AIChE Symp. Ser. Vol. 79 pp. 19-27
  5. Achaichia, A. and Cowell, T. A., 1988, Heat transfer and pressure drop characteristics of flat tube and louvered plate fin surfaces, Exp. Thermal Fluid Science, Vol. 1 pp. 147-157 https://doi.org/10.1016/0894-1777(88)90032-5
  6. Sunden, B. and Svantessen, J., 1992, Correlation of j and f factors for multi-louvered heat transfer surfaces, In:Proceedings of Third UK National Heat Transfer Conference, pp. 805-811
  7. Chang, Y. J. and Wang, C. C., 1996, Air-side performance of brazed aluminum heat exchangers, J. Enhanced Heat Transfer, Vol. 3, No. 1, pp. 15-28 https://doi.org/10.1615/JEnhHeatTransf.v3.i1.20
  8. Kim, M. H. and Park, W. Y., 1998, Air-side heat transfer and pressure drop characteristics of louvered fin heat exchangers, Proceedings of the KSME '98 fall conference, pp. 123-128
  9. Sahnoun, A. and Webb, R. L, 1992, Prediction of heat transfer and friction for the louver fin geometry, J. Heat Transfer, Vol. 114 pp. 893-900 https://doi.org/10.1115/1.2911898
  10. Achaichia, A. and Cowell, T. A., 1988, A finite difference analysis of fully developed periodic laminar flow in inclined louvered arrays, In:Proceedings of Second UK National Heat Transfer Conference, Glassgow, pp. 883-888
  11. Hiramatsu, M., Ishimaru, T. and Matsuzaki, K., 1990, Research on fins for air-conditioning heat exchangers (first report, numerical analysis of heat transfer on louvered fins), JSME International Journal, Series II, Vol. 33, Paper No. 88-1254A
  12. Suga, K., Aoki, H. and Shingawa, T., 1990, Numerical analysis on two dimensional flow and heat transfer on louvered fins using overlaid grids, JSME International Journal, Vol. 33 pp. 122-127
  13. Achaichia, A., Heikal, M. Y., Sulaimna, Y. and Cowell, T. A., 1994, Numerical Investigation of flow and friction in louver fin arrays, In:Proceedings of the Tenth International Heat Transfer Conference, Vol. 4, pp. 333-338
  14. Tafti, D. K., Wang, G. and Lin, W., 2000, Flow transition in a multi-louvered fin array, Int. J. Heat Mass Transfer, Vol. 43 pp. 901-919 https://doi.org/10.1016/S0017-9310(99)00190-8
  15. Kang C. S. and Choi, T. M., 1993, A basic study on air flow characteristics in louvered fins, KSME J., Vol. 17, No. 5, pp. 1276-1293
  16. Lee, K. S., Jeon, C. D. and Lee, J. H., 1994, Study of flow structure and pressure drop characteristics in louvered-fin type heat exchanger, J. SAREK, Vol. 6, No. 2, pp. 140-154
  17. Park, B. S., Cho, J. H. and Han, C. S., 2001, Three dimensional analysis for the performance of the corrugated louver fin for a vehicle heat exchanger. Proceedings of SAREK 2001 summer conference, pp. 431-441
  18. Osada, H., Aoki, H., Ohara T. and Kuroyanagi, K., 1999, Experimental analysis for enhancing automotive evaporator fin performance, in Proceedings of the International Conference on Compact Heat Exchangers and Enhancement Technologies for the Process Industries, pp. 439-445
  19. Kim, M. H., Youn, B. and Bullard, C. W., 2001, Effect of inclination on the airside performance of a brazed aluminum heat exchanger under dry and wet conditions, Int. J. Heat Mass Transfer, Vol. 44 pp. 4613-4623 https://doi.org/10.1016/S0017-9310(01)00104-1
  20. Groehn, H. G., 1983, Heat transfer and flow resistance of yawed tube bundle heat exchangers, Heat Exchanger:Theory and Practice, Hemisphere, Washington, DC, pp. 299- 310
  21. Monheit M. and Freim, J., 1986, Effect of tube bank inclination on the thermal hydraulic performance of air cooled heat exchangers, in Proceedings of 8th Int. Heat Transfer Conf., pp. 2727-2732
  22. Chang, W. R., Wang, C. C. and Chang, Y. J., 1994, Effect of an inclination angle on the heat transfer and pressure drop characteristics of a wavy finned-tube heat exchanger, ASHRAE Trans., Vol. 100, No. 2, pp. 826-832
  23. ASHRAE Standard 41.1, 1986, Standard method for temperature measurement, ASHRAE
  24. ASHRAE Standard 41.2, 1987, Standard method for laboratory air-flow measurement, ASHRAE
  25. Gnielinski, V., 1976, New equations for heat and mass transfer in turbulent pipe flows, Int. Chem. Eng., Vol. 16, pp. 359-368
  26. Shah, R. K., 1985, Compact heat exchangers, in Handbook of Heat Transfer Applications, Rohsenow W. M. et al. eds., pp. 181-200
  27. Kays, W. M. and London, A. L., 1984, Compact Heat Exchangers, McGraw-Hill Books
  28. Webb, R. L., 1990, The flow structure in louvered fin heat exchanger geometry, SAE 900722
  29. Chang, Y. J. and Wang, C. C., 1997, A generalized heat transfer correlation for louver fin geometry, Int. J. Heat Mass Transfer, Vol. 40, No. 3, pp. 533-544 https://doi.org/10.1016/0017-9310(96)00116-0
  30. Kim M. H. and Bullard, C. W., 2002, Air-side thermal hydraulic performance of multi-louvered fin aluminum heat exchangers, Int. J. Refrigeration Vol. 25 pp. 390-400 https://doi.org/10.1016/S0140-7007(01)00025-1
  31. Chang, Y. J., Hsu, K. C., Lin, Y. T. and Wang, C. C., 2000, A generalized friction correlation for louver fin geometry, Int. J. Heat Mass Transfer, Vol. 43 pp. 2237-2243 https://doi.org/10.1016/S0017-9310(99)00289-6