Comparative Study of Advanced Heatsink Structures for Improved Thermal Performance in Axial Flux Motors

Abstract

Additive manufacturing has enabled the use of advanced geometries such as lattice-structures in heatsinks. This study investigates the thermal performance of various advanced heatsink designs in the context of cooling the windings of an axial flux motor using active air cooling. Physical samples of the heatsinks are additively manufactured from an aluminum alloy and tested under realistic airflow conditions. The heatsink designs are compared against an optimized conventional finned geometry based on the measured thermal resistance at a given fan speed. This ensures that the results are representative of real-world use cases and applicable in practical solutions. The results indicate that airfoil-shaped pins can slightly outperform conventional straight fins in thermal resistance while weighing less. In terms of mass-based relative performance, the rhombi octet lattice structure outperformed the other prototypes. These findings reinforce conventional design principles in terms of absolute performance while suggesting that lattice structures can provide higher relative performance in certain weight sensitive applications.