Finite circular fin method for wavy fin-and-tube heat exchangers under fully and partially wet surface conditions

Abstract The present study proposes the finite circular fin method for analyzing the heat and mass transfer characteristics of wavy fin-and-tube heat exchangers under fully and partially wet surface conditions. The analysis is carried out by dividing the wavy fin-and-tube heat exchanger into many tiny segments. The tiny segments can be analyzed based on surface conditions, i.e. fully wet, fully dry or partially wet surface condition. From the experimental results, it is found that the heat and mass transfer characteristics are insensitive to the inlet relative humidity but the effect of relative humidity on mass transfer characteristic become more pronounced when the partially wet surface condition takes place. The heat transfer characteristic is independent of the fin spacing. Effect of fin spacing on mass transfer characteristic is small when fin spacing is larger than 2.5 mm. However, at smaller fin spacing, the mass transfer characteristic slightly decreases when the relative humidity increases. The ratios of h c,o / h d,o C p,a are in the range of 0.6–1.2. Correlations are proposed to describe the heat and mass transfer characteristics. These correlations can describe 95.63% of the heat transfer characteristic within 15% and 95.14% of the mass transfer characteristic within 20%. Correspondingly, 94.68% of the ratios of h c,o / h d,o C p,a are predicted by the proposed correlation within 20%.

[1]  D. P. Sekulic,et al.  Extended surface heat transfer , 1972 .

[2]  Somchai Wongwises,et al.  Finite circular fin method for heat and mass transfer characteristics for plain fin-and-tube heat exchangers under fully and partially wet surface conditions , 2007 .

[3]  Anthony M. Jacobi,et al.  Air-side data interpretation and performance analysis for heat exchangers with simultaneous heat and mass transfer: Wet and frosted surfaces , 2005 .

[4]  Robert J. Moffat,et al.  Describing the Uncertainties in Experimental Results , 1988 .

[5]  S. Wongwises,et al.  A Fully Wet and Fully Dry Tiny Circular Fin Method for Heat and Mass Transfer Characteristics for Plain Fin-and-Tube Heat Exchangers Under Dehumidifying Conditions , 2007 .

[6]  K. Ogawa,et al.  Heat and Mass Transfer Performances on Plate Fin and Tube Heat Exchangers under Dehumidification , 1988 .

[7]  T. R. Bump.  AVERAGE TEMPERATURES IN SIMPLE HEAT EXCHANGERS , 1963 .

[8]  V. Gnielinski.  New equations for heat and mass transfer in turbulent pipe and channel flow , 1976 .

[9]  Vice President,et al.  AMERICAN SOCIETY OF HEATING, REFRIGERATION AND AIR CONDITIONING ENGINEERS INC. , 2007 .

[10]  Chi-Chuan Wang,et al.  Performance of plate finned tube heat exchangers under dehumidifying conditions , 1997 .

[11]  S. Wongwises,et al.  Simultaneous heat and mass transfer characteristics for wavy fin-and-tube heat exchangers under dehumidifying conditions , 2006 .

[12]  R. Webb,et al.  Calculation of Fin Efficiency for Wet and Dry Fins , 1996 .

[13]  Chi-Chuan Wang,et al.  INVESTIGATION OF WAVY FIN-AND-TUBE HEAT EXCHANGERS: A CONTRIBUTION TO DATABANK , 1999 .

[14]  D. Beecher,et al.  Effects of fin pattern on the air side heat transfer coefficient in plate finned tube heat exchangers , 1987 .

[15]  J. W. Ramsey,et al.  Thermal Environmental Engineering , 1970 .

[16]  Hitoshi Asano,et al.  Flow and Heat Transfer Performance of a Plate-Fin and Tube Heat Exchanger (1st report: Effect of fin pitch) , 1994 .

[17]  Wei-Mon Yan,et al.  HEAT TRANSFER AND FRICTION CHARACTERISTICS OF FIN-AND-TUBE HEAT EXCHANGERS , 2000, Proceeding of Proceedings of Symposium on Energy Engineering in the 21st Century (SEE2000) Volume I-IV.

[18]  S. Wongwises,et al.  Heat and Mass Transfer Characteristics for Finned Tube Heat Exchangers with Humidification , 2007 .

[19]  Chi-Chuan Wang,et al.  Performance of the herringbone wavy fin under dehumidifying conditions , 2002 .

[20]  Chi-Chuan Wang,et al.  Comprehensive Study of Convex-Louver and Wavy Fin-and-Tube Heat Exchangers , 1998 .

[21]  Allan D. Kraus,et al.  Compact heat exchangers : a festschrift for A. L. London , 1990 .

[22]  Somchai Wongwises,et al.  A tube-by-tube reduction method for simultaneous heat and mass transfer characteristics for plain fin-and-tube heat exchangers in dehumidifying conditions , 2005 .

[23]  Chi-Chuan Wang,et al.  Heat transfer and friction characteristics of plain fin-and-tube heat exchangers, part II: Correlation , 2000 .

[24]  Chi-Chuan Wang,et al.  Empirical correlations for heat transfer and flow friction characteristics of herringbone wavy fin-and-tube heat exchangers , 2002 .

[25]  Chi-Chuan Wang,et al.  Flow visualization of annular and delta winlet vortex generators in fin-and-tube heat exchanger application , 2002 .

[26]  C. Chang,et al.  Heat transfer and friction characteristics of typical wavy fin-and-tube heat exchangers , 1997 .