Propeller Aerodynamics Under Non-Uniform Inflows
Sara MONTAGNER, Manuel ZANNONE, Jacopo SERPIERI, Gioacchino CAFIERO
Abstract. Urban Air Mobility (UAM) is highly dependent on Unmanned Aerial Vehicles (UAVs) operating in complex urban environments, where propellers often encounter non-uniform inflows. These conditions can deteriorate the performance and stability of the vehicle, making standard uniform-inflow assumptions unrealistic and even dangerous for the prediction of the performance of UAVs. It is therefore of paramount importance to develop the capability to accurately reproduce in a repeatable manner such complex inflow conditions. This paper presents an experimental investigation of a propeller wake under controlled, non-uniform sheared inflow. Using Particle Image Velocimetry (PIV), the wake of a D=0.3 m propeller was characterized when operating in forward flight conditions. A modular fan array generated both uniform baselines and four linear shear rates. The results show that the sheared inflow creates an asymmetric wake with reduced vorticity magnitude and a radial streamtube expansion. Furthermore, Turbulent Kinetic Energy (TKE), highly localized in uniform flow, becomes significantly more diffused under sheared conditions, indicating altered turbulent mixing. These findings highlight the critical impact of the inflow conditions on the on the wake development.
Keywords
UAM, UAVs, Propeller, Non-Uniform Inflow, Aerodynamics
Published online 7/20/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Sara MONTAGNER, Manuel ZANNONE, Jacopo SERPIERI, Gioacchino CAFIERO, Propeller Aerodynamics Under Non-Uniform Inflows, Materials Research Proceedings, Vol. 69, pp 707-712, 2026
DOI: https://doi.org/10.21741/9781644904251-125
The article was published as article 125 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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