Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Experimental Study on the Airside Performance of Fin-and-Tube Heat Exchangers Having Wide Louver Fins Under Wet Conditions

광폭 루버 핀이 장착된 핀-관 열교환기의 습표면 성능에 대한 실험적 연구

  • Kim, Nae-Hyun (Div. of Mechanical System Engineering, Incheon Nat'l Univ.)
  • 김내현 (인천대학교 기계시스템공학부)
  • Received : 2015.02.18
  • Accepted : 2015.07.08
  • Published : 2015.09.01
Download PDF
⟨ Previous Next ⟩

Abstract

One method of increasing the heat-transfer rate is to increase the heat-transfer area. In this study, we test a wide louver fin-and-tube heat exchanger with $P_t/P_l$ = 1.03, and we compare the results with those of a louver fin-andtube heat exchanger with $P_t/P_l$ = 0.6. The results obtained show that the heat-transfer capacities of the wide louver samples are larger (16% in one row, 29% in two rows, and 38% in three row samples) than those of the louver samples. Considering the area ratio of 2.17, the increase in the heat-transfer capacity is somewhat small. The reason for this may be due to the smaller heat-transfer coefficient and fin efficiency of the wide louver sample. The effect of the fin pitch on the j and f factors are not profounded. The j and f factors decreased as the number of tube rows increased. We compare the data obtained with existing correlations.

전열량을 늘리는 손쉬운 방법은 전열면적을 크게 하는 것이다. 본 연구에서는 세로와 가로 방향 튜브 핏치의 비(Pt/Pl)가 1.03인 광폭 루버 핀 시료의 습표면 j와 f 인자를 실험을 통하여 구하고 Pt/Pl=0.6인 일반 루버 핀 시료와 비교하였다. 동일 소비동력에서 광폭 루버 핀 시료의 전열성능이 일반 루버 핀 시료보다 1열에서 평균 16%, 2열에서 평균 29%, 3열에서 평균 38% 크게 나타났다. 이 증가량은 핀 면적의 증가량 (2.17배)에 비하면 현저히 작은데 이는 광폭 루버 핀 시료의 열전달계수와 핀 효율이 일반 루버 핀 시료의 값들보다 작기 때문이다. 핀 핏치가 j와 f 인자에 미치는 영향이 크지 않았다. 또한 튜브 열수가 증가할수록 j와 f 인자는 감소하였다. 실험 데이터를 기존 상관식과 비교하였다.

Keywords

References

  1. Webb, R. L. and Kim, N.-H., 2005, Principles of Enhanced Heat Transfer, 2nd ed., Taylor and Francis Pub.
  2. Wang, C.-C., 1999, "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.
  3. Wang, C.-C. and Chang, C.-T., 1998, "Heat and Mass Transfer for Plate Fin-and-tube Heat Exchangers, with and Without Hydrophilic Coating," Int. J. Heat Mass Transfer, Vol. 41, pp 3109-3120. https://doi.org/10.1016/S0017-9310(98)00060-X
  4. Wang, C.-C, Lin, Y.-T. and Lee, C.-J., 2000, "Heat and Momentum Transfer for Compact Louvered Finand-tube Heat Exchangers in Wet Condition," Int. J. Heat Mass Transfer, Vol. 43, pp. 3443-3452. https://doi.org/10.1016/S0017-9310(99)00375-0
  5. Hong, K. and Webb, R. L., 1999, "Performance of Dehumidifying Heat Exchangers with and Without Wetting Coatings," J. Heat Transfer, Vol. 121, pp. 1018-1026. https://doi.org/10.1115/1.2826052
  6. Ma, X., Ding, G., Zhang, Y. and Wang, K., 2007, "Airside Heat Transfer and Friction Characteristics for Enhanced Fin-and-tube Heat Exchanger with Hydrophilic Coating Under Wet Condition," Int. J. Ref., Vol. 30, pp. 1153-1167. https://doi.org/10.1016/j.ijrefrig.2007.03.001
  7. Saboya, F. E. M. and Sparrow, E. M., 1974, "Local and Average Heat Transfer Coefficients for One-row Plate Fin and Tube Heat Exchanger Configurations," J. Heat Transfer, Vol. 96, pp. 265-272. https://doi.org/10.1115/1.3450189
  8. Kim, N.-H., 2015, "An Experimental Study on the Airside Performance of Fin-and-tube Heat Exchangers Having Wide Louver Fin," Korean J. Air-Conditioning Refrigeration Engineering, Vol. 27, No. 5, pp. 254-262. https://doi.org/10.6110/KJACR.2015.27.5.254
  9. ESDU 98005, 1998, 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.
  10. Park, B.-B., You, S.-M., Yoon, B. and Yoo, K.-C., 1997, "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.
  11. Schmidt, T. E., 1949, "Heat Transfer Calculations for Extended Surfaces," J. of ASRE, Refrigeration Engineering, Vol. 4, pp. 351-357.
  12. ASHRAE Standard 41.5, 1975, Standard Measurement Guide, Engineering Analysis of Experimental Data, ASHRAE.
  13. Wang, C.-C., Lee, W.-S. and Sheu, W.-J., 2001, "A Comparative Study of Compact Enhanced Fin-and-Tube Heat Exchangers," Int. J. Heat Mass Transfer, Vol. 44, pp. 3565-3573. https://doi.org/10.1016/S0017-9310(01)00011-4
  14. Torikoshi, K., Xi, G.-N., Nakazawa. Y. and Asano, H., 1994, "Flow and Heat Transfer Performance of a Plate Fin and Tube Heat Exchanger (First Report: Effect of Fin Pitch)," Proceedings of the 10th Int. Heat Transfer Conf., Vol. 4, pp. 411-416.