Design optimization and comparative evaluation of oval and toroidal propeller geometries versus a conventional propeller

Rayn Nasr; Majd Shreif; Enrico Abou Jaoude; Celine Ahmar; Jihad Rishmany

doi:10.59400/sv3889

Design optimization and comparative evaluation of oval and toroidal propeller geometries versus a conventional propeller

Rayn Nasr
Department of Aerospace Science and Technology, Politecnico di Milano, 20156 Milan, Italy
Majd Shreif
Department of Mechanical Engineering, Faculty of Engineering, University of Balamand, Tripoli P.O. Box 100, Lebano
Enrico Abou Jaoude
Department of Mechanical Engineering, Faculty of Engineering, University of Balamand, Tripoli P.O. Box 100, Lebano
Celine Ahmar
Department of Mechanical Engineering, Faculty of Engineering, University of Balamand, Tripoli P.O. Box 100, Lebano
Jihad Rishmany
Department of Mechanical Engineering, Faculty of Engineering, University of Balamand, Tripoli P.O. Box 100, Lebano

Article ID: 3889

Keywords: toroidal propellers; aeroacoustics; propeller geometry optimization; aerodynamic performance analysis; noise reduction in unmanned aerial vehicles (UAVs); thrust efficiency; computational fluid dynamics (CFD)

Abstract

Drones are increasingly used in delivery, aerial imaging, search and rescue, and agricultural monitoring due to their low cost, low emissions, and ability to reach hazardous or hard-to-access locations. However, a major limitation is the high noise produced by conventional propellers as they interact with the air. Recently, toroidal propellers have emerged as a promising alternative, offering aerodynamic benefits that can reduce noise while maintaining or improving thrust generation. This study investigates the performance of toroidal propellers, both circular and oval, compared to a conventional propeller. The assessment focuses on thrust production, efficiency, and noise emission using both experimental testing and numerical simulations. Results indicate that toroidal propellers provide notable advantages. Experiments showed approximately a 15 dB noise reduction and up to a fourfold increase in thrust relative to the conventional design. Simulations revealed that the oval toroidal propeller achieved the lowest noise level at 29.54 dB, while the circular design produced higher noise but delivered the greatest thrust, reaching 44.08 N. Overall, the study demonstrates that toroidal propellers can significantly enhance drone performance. The optimal choice between oval and circular designs depends on specific mission requirements, balancing noise reduction against thrust demand.

Published

2026-03-11

How to Cite

Nasr, R., Shreif, M., Abou Jaoude, E., Ahmar, C., & Rishmany, J. (2026). Design optimization and comparative evaluation of oval and toroidal propeller geometries versus a conventional propeller. Sound & Vibration, 60(2). https://doi.org/10.59400/sv3889

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Vol. 60 No. 2 (2026): in progress

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This work is licensed under a Creative Commons Attribution 4.0 International License.

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