Numerical Analysis of Laminar Flow and Heat Transfer in Internally Finned Tubes

In this study, fully developed laminar flow and convective heat transfer in an internally finned tube heat exchanger are investigated numerically. The flow is assumed to be both hydrodynamically and thermally developed with uniform outside wall temperature. Parameters of the thickness, length, and number of fins and thermal conductivity ratio between fin and working fluid are varied to obtain the friction factor as well as Nusselt number. The results show that the heat transfer improves significantly if more fins are used; however, the pressure drop turns out to be large in this heat exchanger. In addition, it is found that the emergence of closed-loop isotherms between the areas of two neighboring fins leads to heat transfer enhancement in the internally finned tube. When the fin number is smaller than 14, there appears a maximum Nusselt number at about 0.8 of the dimensionless fin length. Finally, an experiment is conducted to verify the numerical results.

[1]  B. Shome,et al.  Mixed convection laminar flow and heat transfer of liquids in isothermal horizontal circular ducts , 1995 .

[2]  B. Shome.  MIXED CONVECTION LAMINAR FLOW AND HEAT TRANSFER OF LIQUIDS IN HORIZONTAL INTERNALLY FINNED TUBES , 1998 .

[3]  B. Shome,et al.  Experimental Investigation of Laminar Flow and Heat Transfer in Internally Finned Tubes , 1997 .

[4]  O. Zeitoun,et al.  Heat transfer for laminar flow in internally finned pipes with different fin heights and uniform wall temperature , 2004 .

[5]  P. Ghoshdastidar,et al.  A study of heat transfer effectiveness of circular tubes with internal longitudinal fins having tapered lateral profiles , 2002 .

[6]  A. Al-Sarkhi,et al.  Characteristics of forced convection heat transfer in vertical internally finned tube , 2005 .

[7]  B. Rabi Baliga,et al.  Computational optimization of the thermal performance of internally finned ducts , 2009 .

[8]  Y. Chang,et al.  Optimization of Finned Tubes for Heat Transfer in Laminar Flow , 1973 .

[9]  M. N. Özişik,et al.  Finite Difference Methods in Heat Transfer , 2017 .

[10]  Muhammad M. Rahman,et al.  Experimental measurements of heat transfer in an internally finned tube , 1998 .

[11]  H. Soliman,et al.  Analysis of fully developed laminar flow in longitudinal internally finned tubes , 1977 .

[12]  Numerical analysis of laminar mixed convection in horizontal internally finned tubes , 1990 .

[13]  G. Ledezma,et al.  Computation of the nusselt number asymptotes for laminar forced convection flows in internally finned tubes , 1999 .

[14]  Curtis F. Gerald,et al.  APPLIED NUMERICAL ANALYSIS , 1972, The Mathematical Gazette.

[15]  NUMERICAL STUDY OF LAMINAR HEAT TRANSFER IN INTERNALLY FINNED TUBES , 1991 .

[16]  Chii-Dong Ho,et al.  Collector efficiency improvement of recyclic double-pass sheet-and-tube solar water heaters with internal fins attached , 2008 .

[17]  A. Trupp,et al.  Analysis of Laminar Heat Transfer in Internally Finned Tubes with Uniform Outside Wall Temperature , 1980 .

[18]  Tilak T. Chandratilleke,et al.  Laminar convective heat transfer in a microchannel with internal longitudinal fins , 2009 .

[19]  Krishnaswamy Nandakumar,et al.  Heat Transfer in Internally Finned Tubes , 1976 .

[20]  T. C. Carnavos.  Cooling Air in Turbulent Flow with Internally Finned Tubes , 1979 .

[21]  T. C. Carnavos.  Heat Transfer Performance of Internally Finned Tubes in Turbulent Flow , 1980 .