Performance of Thermally Radiating Fractal Extended Surfaces of Varying Cross-Section

摘要

The thermal performance of fractal fins with varying cross-sectional profiles thermally radiating to free space was computationally examined. The Sierpinski carpet fractal pattern was used to increase the surface area and decrease the system mass of extended surfaces used in waste heat rejection systems. Fin effectiveness per unit was used to quantify the thermal performance of the Sierpinski carpet extended surfaces of varying cross-sectional profile. The use of non-uniform cross-sectional profiles was found to increase the effectiveness per unit mass of Sierpinski carpet extended surfaces thermally radiating to free space. At higher order fractal iterations the use of non-uniform cross-sectional profiles also resulted in an increase in fin efficiency. The utilization of the Sierpinski carpet fractal pattern in combination with a non-uniform cross-sectional profile results in a significant increase in fin effectiveness per unit mass when compared with traditionally employed longitudinal fins of rectangular profile.