Optimum profiles for asymmetrical longitudinal fins in annular ducts

In the present work the geometry of annular ducts with asymmetrical longitu dinal fins is optimized in order to enhance the heat transfer under laminar coolant flow conditions. The heat transferred is also ma;maximized for a g iven amount of material material or hydraulic resistance, Polynomial profil es are assigned to the two lateral fin surfaces. Velocity and temperature d istributions on the annular duct cross section are determined with the help of a finite-element model. A global heat transfer coefficient and an equiv alent Nusselt number ape then calculated. Lastly, optimum asymmetrical fins obtained by means of a genetic algorithm are shown for different situation s and their performance is compared with those of optimum symmetrical fins.