Effect of Microstructure Surface Geometry on Drone Propeller Efficiency and Performance

Abstract

Previous studies have shown the effectiveness of engineered surfaces on reducing the boundary layer separation in airfoils. To continue that research effort, this study investigates the effect of varying the geometry of these engineered surfaces has on the performance of propeller blades. Custom symmetric propeller blades, with angles of attack of 10, 20, 15 and 25 degrees, covered with micrometer scale pillar arrays were tested to measure thrust and torque as a function of rotational speed. The results point to an overall degradation in performance which could be attributed to scaling issues between the ratio of pillar height and boundary layer thickness. By optimizing this ratio and maintaining a hydrodynamically smooth surface over the entire surface area of the propeller blade, is it hypothesized that the performance improvements seen in previous studies will be obtained in future propellers.