本研究係有關於裂口型熱交換器空氣側熱傳特性之簡化分析方法，其目的在提供一快速且簡單的分析方法，其誤差在工程設計上為可接受的範圍，藉以取代傳統利用實驗研究或理論分析等方式來獲得裂口型熱交換器之熱傳因子與摩擦因子。
本研究將裂口型熱交換器概分為平板、垂直壁面、圓柱體與平板管等元件之集成，並利用流體流經上述各元件之已知熱流經驗公式來計算熱交換器之熱傳性能，同時將結果與文獻所提出的實驗值相比較，從而驗證本數值方法的有效性與精確性。

A simplified numerical method to estimate the airside heat transfer performance for slit fin-and-tube heat exchangers is established in the present study. Compared with the conventionally experimental study or numerical analyses, this approach provides an efficiently analytical method with an acceptable accuracy in engineering designs to calculate the Colburn j factor and the friction factor of the slit fin-and-tube heat exchangers.
In order to achieve the objective, the heat exchangers for the problem of interest are reviewed as an integration of components including plates, vertical walls, cylinders and flat ducts. The well-known laminar or turbulent correlations of Nusselt number and skin-friction coefficients for these components are applied to compute the airside performance of the heat exchangers. The effectiveness and accuracy of the present method are verified by comparing the results obtained here with the experimental ones published previously.

[1] Kays, W. M., and London, A. L., 1984, Compact Heat Exchangers.3rd ed. McGraw-Hill, New York.
[2] Jang, J. Y., Wu, M. C., Chang, W. J., “Numerical and experimental studies of three-dimensional plate-fin and tube heat exchanger”, International journal heat and mass transfer, Vol.39, No.14, 1996.
[3] Rich, D. G., 1973, “The Effect of Fin Spacing on the Heat Transfer and Fraction Performance of Milti-Row, Smooth Plate Fin-and-Tube Heat Exchanger,” ASHRAE Transaction, Vol. 79, part 2, pp. 135-145.
[4] Rich, D. G., 1975, “The Effect of the Numbers of Tube on Heat Transfer Performance of Smooth Plate Fin-and-Tube Heat Exchangers,” ASHRAE Transaction, Vol. 81, part 1, pp. 307-312.
[5] Gray, D. L., and Webb, R. L., 1984, “Heat Transfer and Friction Correlations for Plate-Finned-Tube Heat Exchangers having Plain Fins,” Proc. 8th International heat transfer conference, 1986, pp. 2745-2750.
[6] Seshimo, Y., and Fujii, M., 1991, “An Experimental Study of the Performance of Plate Fin and Tube Heat Exchangers at Low Reynolds Number,” ASME/JSME thermal engineering joint conference, Vol. 4, pp. 449-454.
[7] Wang, C. C., Hsieh, Y. C., Chang, Y. J., and Lin, Y. T., 1996, “Sensible Heat and Friction Characteristics of Plate Fin-and-Tube Heat Exchangers Having Plane Fins,” International journal of refrigeration, Vol. 19(4), pp. 223-230.
[8] Giovannoni, F., and Mattarolo, L., 1983, “Experimental Researches on the Finned Tube Heat Exchangers with Corrugated Fins,” International congress of refrigeration proceedings tome II, B.1-493, pp. 215-220.
[9] Jang, J. Y., Chen, L. K., “Numerical analysis of heat transfer and fluid-flow in a three-dimensional wavy-fin and tube heat exchanger”, International journal heat and mass transfer, Vol.40, No.16, 1997.
[10] Achaichia, A., and Cowell, T. A., 1988, “Heat Transfer and Pressure Drop Characteristics of Flat Tube and Louvered Plate Fin Surface,” Experimental thermal and fluid Science, Vol. 1, pp. 147-157.
[11] Wang, C. C., Chang, Y. P., Chi, K. Y., Chang, Y. J., “A study of non-redirection louver fin-and-tube heat exchanger”, Proc. Instn. Mech engrs,Vol.212 part C, 1998.
[12] Wang, C. C., Chi, K. Y., Chang, Y. J., “An experimental study of heat transfer and friction characteristics of typical louver fin-and-tube heat exchangers”, International journal of heat and mass transfer, Vol.41, 1998.
[13] Suga, K., Aoki, H., Shinagawa, T., “Numerical analysis on two-dimensional flow and heat transfer of louvered fins using overlaid grids”, JSME international journal series Ⅱ, Vol.33, No.1, 1990.
[14] Suga, K., Aoki, H., “Numerical study on heat transfer and pressure drop in multi louvered fins”, ASME/JSME thermal engineering proceeding, Vol.4, 1991.
[15] Hiramatsu, M., Ishimaru, T., Matsuzaki, K., “Research on fins air conditioning heat exchangers” JSME international journal seriesⅡ, Vol.33, No.4, 1990.
[16] Webb, R. L., Trauger, P., “Flow structure in the louvered fin heat exchanger geometry”, Experimental thermal and fluid science, Vol.40, No.3, 1991.
[17] Hatada, T., Senshu, T., “Experimental study on heat transfer characteristic of convex louver fin for air conditioning heat exchangers” ASME paper 84-HT-74, 1984.
[18] Hadata, T., “Improved heat transfer performance of air coolers by strip fins controlling air flow distribution “, ASHRAE Trans. Part1, 1989.
[19] Bemisderfer, C. H., “Heat transfer: a contemporary analytical tool for developing improved heat transfer surfaces”, ASHRAE Trans. Part1, 1987.
[20] Pauley, L. L., Hodgson, J. E., “Flow visualization of convex louver fin array to determine maximum heat transfer conditions”, Experimental thermal and fluid science, Vol.9, 1994.
[21] Spring, M. E., Thole, K. A., “Experimental design for flow field studies of louvered fins”, Experimental thermal and fluid science Vol. 18, pp. 258-269 1998.
[22] Tafti, D. K., Wang, G., Lin W., ”Flow transition in a multi-louvered fin array”, International journal of heat and mass transfer, 2000.
[23] Wang, C. C., Chen, P. Y., Jang, J. Y., “Heat transfer and friction characteristics of convex-louver fin-and-tube heat exchanger”, Experimental heat transfer, Vol.9, 1996.
[24] Wang, C. C., Tsai, Y. M., Lu, D. C., “Comprehensive study of convex-louver and wavy fin-and-tube heat exchangers” International journal of thermophysics and heat transfer, Vol.12, No.3, 1998.
[25] Liu, M. S., Leu, J. S., Shyu, R. J., Wang, C. C., ”Effect of successively variable louver angle on the airside performance of fin-and-tube heat exchangers”, ASHRAE Trans., 2000.
[26] Wang, C. C., Lee, C. J., Chang, C.T., Lin, S.P., “Heat transfer and friction correlation for compact louvered fin-and-tube heat exchangers”, International journal of heat and mass transfer, Vol.42, pp. 1945-1956, 1999.
[27] Wang, C. C., Chi, K. U., “Heat transfer and friction characteristics of plain fin-and-tube heat exchangers,part2： correlation”, International journal of heat and mass transfer, Vol.43, pp. 2692-2700, 2000c.
[28] Dejong, N. C., Jacobi, A. M., “An experimental study of flow and heat transfer in parallel-plate arrays： local, row-by-row and surface average behavior.”, International journal of heat and mass transfer, Vol.40, pp. 1365-1378, 1997.
[29] Nakayama, W., Xu, L. P., “Enhanced fins for air-cooled heat exchangers heat transfer and friction correlations.”, Proceeding of the first ASME/JSME thermal engineering joint conference, Vol.1, pp. 495-502, 1983.
[30] Garimella, S., Coleman, J. W., “Wicht, tube and fin geometry alternatives for the design of absorption-heat-pump heat exchangers”, Journal of enhanced heat transfer 4, pp. 217-235, 1997.
[31] Churchill, S. W., and Bernstein, M., “A correlating equation for forced convection from gases and liquids to a circular cylinder in crossflow”, Journal of heat Transfer, 99, 300-306, 1977.
[32] Holman, J. P., 1997, Heat Transfer, 8th ed. McGraw-Hill, New York.
[33] Bejan, A., 1995, Convection Heat Transfer, ed. Wiley, New York.
[34] Webb, R. L., Principles of Enhanced Heat Transfer, John Wiley & Sons,Inc., 1994.
[35] Kuppan, T., 2002, Heat Exchanger Design handbook, ed. Dekker, New York.
[36] Wang, C. C., Tao, C. J., Chang, C. J., “An investigation of the airside performance of the slit fin-and tube heat exchangers”, International journal of Refrigeration, Vol.22, pp.595-603, 1999.
[37] Wang, C. C., Du, Y. J., “An experimental study of the airside performance of the superslit fin-and-tube heat exchangers”, International journal of heat and mass transfer, Vol.43, pp.4475-4482, 2000.
[38] Wang, C. C., Lee, W. S., Sheu, W. J., “A comparative study of compact enhanced fin-and-tube heat exchangers”, International journal of heat and mass transfer, Vol.44, pp.3565-3573, 2001.
[39] Evans H. L., Mass Transfer through Laminar Boundary Layers. Further Similar Solutions to the B-equation for B=0, International journal of heat mass transfer, Vol. 5, pp. 35-37, 1962.
[40] Dittus P. W. and Boelter L. M. K., “Heat transfer in automobile radiators of the tubular type”, International Communication Heat Mass Transfer, Vol. 12, 1985, pp. 3-22.
[41] Schlichting H., Boundary Layer Theory, 7th ed., McGraw-Hill, New York(1979).
[42] Howarth L., “On the Solution to the Laminar Boundary Layer Equations”, Proc. R. Soc. London Ser. A, Vol. 164, 1938,p.547.
[43] Hartree D. R., ”On an equation occurring in Falkner and Skan’s approximate treatment of the equations of the boundary layer”, Proc. Cambridge Phil. Soc., Vol.33, Part 2, 1937,p.223-239.
[44] 王啟川，熱交換器設計，五南圖書出版。
[45] Beavers G. S., Low Reynolds Number Flow in Large Aspect Ratio Rectangular Ducts, J. Basic Eng., Vol. 93, pp. 296-299,1971.
[46] Zukauskas A. A., Konvektivnyi perenos v teploobmennikakh, Nauka, Moscow, pp. 472, 1982.
[47] Zukauskas A. A. and Ulinskas R., Banks of plain and finned tubes, Heat exchanger design handbook, Vol. 2, Section 2.2.4, Hemisphere, New York, 1983.
[48] Wieting A. R., Empirical Correlations for Heat Transfer and Flow Friction Characteristics of Rectangular Offset-Fin Plate-Fin Heat Exchangers, Journal of. Heat Transfer, Vol. 97, pp 488-490, 1975.
[49] Mochizuki, S., Yagi, Y. and Yang, W. J., Transport phenomena in stacks of interrupted parallel-plate surfaces. Experimental Heat Transfer, Vol. 1,pp. 127-140, 1987.
[50] Mochizuki, S., Yagi, Y. and Yang, W.J., Flow pattern and turbulence intensity in stacks of interrupted parallel-plate surface. Experimental Thermal Fluid Science, Vol. 1, pp. 51-57, 1988.
[51] Joshi, H. M., and Webb, R. L., Heat Transfer and Friction in the Offset Strip-Fin Heat Exchanger. International journal of heat and mass transfer, Vol. 30, pp. 69-84, 1987.
[52] Manglik, R. M., and Bergles, A. E., Heat Transfer and Pressure Drop Correlation for the Rectangular Offset Strip Fin Compact Heat Exchanger, Experimental thermal fluid Science, Vol. 10, pp. 171-180, 1995.
[53] Xi, G. N. and Suzuki, K., A Flow Visualization Experiment on the Instability of Wakes of Plates for Performance Study of Compact Heat Exchangers, Proc. 2nd Int. Symp. Heat Transfer, Beijing, Vol. 2, p.638-643, 1988.
[54] Mercier, P. and Tochon, P., Analysis of Turbulent Flow and Heat Transfer in Compact Heat Exchanger by Pseudo Direct Numerical Simulation., Compact Heat Exchangers for the Process Industries, ed. R. K. Shah, Begell House Inc., New York, p. 223-230, 1997.
[55] Toossi,R., Asheghi, M, and Hou, K. S., Effect of Fluid Properties onHeat Transfer in Channels with Offset Strip Fins, Experimental Heat Transfer, Vol. 7, pp. 189-202, 1994.
[56] Xi, G. N., and Shah, R. K., Numerical Analysis of Offset Strip Fin Heat Transfer and Flow Friction Characteristics, Proceedings of Int. conference on computational heat and mass transfer, pp. 75-87, Northern Cyprus, 1999.