Effect of Groove Size on Aerodynamic Performance of a Low Reynolds Number UAV Propeller

Abstract

Small-scale propellers typically have low aerodynamic efficiency. Improving the aerodynamic performance and efficiency of these propellers will enhance the endurance and operational range of UAVs. The desired requirement is a propeller design that can produce improved thrust and reduced torque. In order to fulfil such an objective, a novel technique known as the grooved design is studied on a small-scale propeller. Numerical investigations are performed on Applied Precision Composites 10×7 Slow Flyer propeller. Computational Fluid Dynamics is used to analyze this novel design. The grooved cross-sections considered have a rectangular geometry measuring 0.1×0.1mm and 0.1×0.2mm which are placed at 0.09c, 0.17c, 0.32c and 0.42c from the leading edge. The results of the study showed that the presence of grooves had modified the flow characteristics only to detrimentally impact the thrust performance. However, the grooves improved power performance due to torque reduction. The analysis of the KP results showed, in most models, the low torque relative to the baseline in the operational range of the low to medium advance ratio range. The improvement in torque, however, did not improve efficiency in all models.