Radiant Fin Performance Using Fractal-like Geometries

Abstract

The results of a computational study into the thermal performance of thermally radiating fractal-like fins are presented. Previous experimental studies have shown that fractal patterns increase the heat transfer surface area while simultaneously reducing mass. Two fractal patterns were used for comparison, the modified Koch snowflake and the Sierpinski carpet. For an isothermal base fin radiating to free space, the fin effectiveness and fin efficiency are presented for the zeroth and first four fractal iterations in order to quantify the performance. Emissivity, width/thickness ratio, base temperature, and fin material were varied to better understand their impact on the performance of fractal-like fins. Based upon the observed results, fractal-like fins greatly improve the fin effectiveness per unit mass. In certain cases, fin effectiveness per unit mass was found to increase by up to 46%. As the cost of access to space is significant, this reduction in mass could lead to savings for spacecraft thermal management applications.