Optimum Profiles for Asymmetrical Longitudinal Fins in Annular Ducts

In the present work the geometry of annular ducts with asymmetrical longitudinal fins is optimized in order to enhance the heat transfer under laminar coolant flow conditions. The heat transferred is also maximized for a given amount of material or hydraulic resistance. Polynomial profiles are assigned to the two lateral fin surfaces. Velocity and temperature distributions on the annular duct cross section are determined with the help of a finite-element model. A global heat transfer coefficient and an equivalent Nusselt number are then calculated. Lastly, optimum asymmetrical fins obtained by means of a genetic algorithm are shown for different situations and their performance is compared with those of optimum symmetrical fins.

[1]  R. Duffin,et al.  A Variational Problem Relating to Cooling Fins , 1959 .

[2]  Nestor V. Queipo,et al.  Genetic algorithms for thermosciences research: application to the optimized cooling of electronic components , 1994 .

[3]  Y. Tsukamoto,et al.  Shape optimization problem for minimum volume fin , 1984 .

[4]  G. Fabbri.  A genetic algorithm for fin profile optimization , 1997 .

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

[6]  Giampietro Fabbri,et al.  Heat transfer optimization in internally finned tubes under laminar flow conditions , 1998 .

[7]  R. Shah,et al.  Compact Heat Exchangers , 1990 .

[8]  Arthur David Snider,et al.  OPTIMAL FIN PROFILES - CLASSICAL AND MODERN , 1990 .

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

[10]  Ephraim M Sparrow,et al.  Forced Convection Heat Transfer from a Shrouded Fin Array with and without Tip Clearance , 1978 .

[11]  Giampietro Fabbri,et al.  Heat transfer optimization in finned annular ducts under laminar-flow conditions , 1998 .

[12]  A. Aziz.  Optimum Dimensions of Extended Surfaces Operating in a Convective Environment , 1992 .

[13]  Abdul Aziz,et al.  Optimum design of radiating and convecting-radiating fins , 1996 .

[14]  Arthur David Snider,et al.  The Quest for the Optimum Longitudinal Fin Profile , 1987 .

[15]  Giampietro Fabbri,et al.  Optimization of heat transfer through finned dissipators cooled by laminar flow , 1998 .

[16]  Avram Bar-Cohen,et al.  Advances in Thermal Modeling of Electronic Components and Systems, Vol. 1 , 1988 .