Validation of a Surrogate-Based Methodology for Low-Noise UAV/UAM Rotor Design

Abstract

One of the main problems of the Unmanned Aerial Vehicles (UAV) and Urban Air Mobility (UAM) markets is the noise generated by these aircraft. The work focuses on the development of a design methodology for low-noise, high-efficiency propellers. The method's capabilities were demonstrated and validated through multi-objective UAV propeller optimization, the manufacture of technology demonstrators, and tests on a dedicated test stand within an anechoic chamber. The developed acoustic facility proved capable of providing high-quality propeller acoustic and performance measurements required for validation purposes. The proposed surrogate-based optimization framework allowed to find a set of non-dominated solutions improved relative to the benchmark baseline, both in terms of aerodynamic performance and noise level. The observed optimization direction and the characteristics of the resultantl geometries align with the expectations and trends outlined in the existing literature. The conducted experimental studies allowed to verify the predicted improvements, revealing the challenges tied to the numerical prediction of low-Reynolds number propeller performance and the necessity of minimizing undesirable noise sources in experimental studies.