Note on the Performance of an Optimal Straight Rectangular Fin with a Semicircular Cut at the Tip

Abstract

A method is proposed for reducing the weight of a straight rectangular fin by providing a semicircular cut at its tip. Finite element analysis is used to compute the temperature distributions and estimate the fin efficiency values. A fin comparison factor (FCF) is defined to take into account the simultaneous reduction in the weight of an otherwise optimized fin [1[f and the corresponding heat transfer rate. Typical values of fin efficiency and FCF for the proposed fin are 66.85% and 1.22 at a Biot number of 0.1048 and a cut-size ratio of 0.798. If the same fins were arranged in an array, under identical convectiue conditions and when the pitch is equal to the thickness, the efficiency of the array is estimated to be 68.05%.