On the aerodynamic performance of redundant propellers for multi-rotor eVTOL in Cruise

Zhang, T., Barakos, G.N. and Furqan, (2024) On the aerodynamic performance of redundant propellers for multi-rotor eVTOL in Cruise. Aerospace Science and Technology, 145, 108846. (doi: 10.1016/j.ast.2023.108846)

Abstract

As multi-rotor and convertible configurations gain compelling popularity in Advanced Air Mobility designs, the handling of redundant propellers during cruise flight regimes becomes a new challenge. This paper presents a systematic study of the aerodynamic performance of feathered and windmilling redundant propellers on a simplified multi-rotor, multi-wing configuration. High-fidelity CFD simulations were performed with a systematic test matrix including the blade feathering angle, azimuth shift, coning angle, and windmilling pitch angle and RPM. For the feathered blades, the feathering angle had a strong impact on the aerodynamic performance. The feathered blades could substantially reduce the overall lift and increase the overall drag at high feathering angles(up to 25% lift reduction and 70% drag increase). This correlated with changes in the sectional wing inflow angles induced by the upstream feathered blades. Windmilling propellers, in ideal cases, were found capable of considerable wind energy extraction (50% of required cruise power) and could create slowed inflows for downstream thrusting propellers, at the cost of excessive drag (up to 90% more). Comparisons of vehicle performance with feathered and windmilling blades, showed similar aerodynamic forces and energy consumption. This shows that windmilling could be a feasible option for redundant propellers, given careful balancing of the drag and energy conversions. The presented results provide valuable guidance for the handling of redundant blades, for future multi-rotor aircraft designs for sustainable aviation.

• Item Type: Articles
• Additional Information: The authors would like to acknowledge GKN Aerospace for their support and approval of publication. The authors would also like to acknowledge the Sulis Tier 2 HPC platform hosted by the Scientific Computing Research Technology Platform at the University of Warwick, funded by EPSRC Grant EP/T022108/1 and the HPC Midlands+ consortium.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Barakos, Professor George

Creator Roles

Barakos, G.: Writing – review and editing, Writing – original draft, Supervision, Software, Resources, Project administration, Methodology, Investigation, Conceptualization

• Authors: Zhang, T., Barakos, G.N., and Furqan,
• College/School: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity
• Journal Name: Aerospace Science and Technology
• Publisher: Elsevier
• ISSN: 1270-9638
• ISSN (Online): 1626-3219
• Published Online: 23 December 2023
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Aerospace Science and Technology 145:108846
• Publisher Policy: Reproduced under a Creative Commons License