Hybrid Rotor Noise Optimization

This study examines noise reduction strategies for unmanned aerial vehicles (UAVs) in urban air mobility applications, with a particular focus on package delivery. By employing a combination of low-, mid- and high-fidelity aerodynamic and aeroacoustic analyses, this research investigates the impact of rotor design parameters, including blade spacing and rotational speed, on noise emissions. The results demonstrate that an increase in rotor spacing results in a reduction in noise emissions. By adjusting the blade chord and twist within an optimization loop, it was possible to decrease tonal noise, yielding a Sound Pressure Level (SPL) reduction of about 3.51 dB while improving propulsive efficiency by 39%. These findings highlight the importance of rotor geometry optimisation during the early design stages in order to meet both performance and noise requirements. © 2025 by the authors.     «

This study examines noise reduction strategies for unmanned aerial vehicles (UAVs) in urban air mobility applications, with a particular focus on package delivery. By employing a combination of low-, mid- and high-fidelity aerodynamic and aeroacoustic analyses, this research investigates the impact of rotor design parameters, including blade spacing and rotational speed, on noise emissions. The results demonstrate that an increase in rotor spacing results in a reduction in noise emissions. By ad...     »

Funding text 1 The authors want to thank ANSYS for providing the simulation software used for the numerical investigations and the Gauss Centre for Supercomputing e.V. ( www.gauss-centre.eu ; accessed on 17 March 2025) for funding this project by providing computing time on the GCS Supercomputer SuperMUC at Leibniz Supercomputing Center (LRZ, www.lrz.de ; accessed on 17 March 2025). Funding text 2 The project \u201CHyRoNo\u2013Noise Reduction of Multi-Rotor-Concepts\u201D is funded within the Bavarian Aviation Research Program-Holistic Air Mobility Initiative Bavaria (HAM-2208-0013) by the Bavarian Ministry of Economic Affairs, Regional Development and Energy. This funding is greatfully acknowledged.     «

Funding text 1 The authors want to thank ANSYS for providing the simulation software used for the numerical investigations and the Gauss Centre for Supercomputing e.V. ( www.gauss-centre.eu ; accessed on 17 March 2025) for funding this project by providing computing time on the GCS Supercomputer SuperMUC at Leibniz Supercomputing Center (LRZ, www.lrz.de ; accessed on 17 March 2025). Funding text 2 The project \u201CHyRoNo\u2013Noise Reduction of Multi-Rotor-Concepts\u201D is funded within t...     »