Acoustic Stall Detection of Variable Pitch Propeller for Unmanned Aerial Vehicles

This paper presents an analysis of acoustic emission and performance data of a UAV rotor equipped with a variable pitch propeller. The proposed study aims to show propeller noise features that indicate stall flow regime on the blade. Analysis of the noise characteristics around the propeller in terms of power spectral density allow to detect the stall. The study shows that a microphone located at different angles around the propeller can provide data sufficient to determine if the blade angle of attack has forced the propeller into the stall regime. In this range, the propeller’s efficiency in hover decreases and leads to an increase in power consumption. The reresearch is a suggests a method of data treatment to obtain a single parameter indicating a blade stall.