Blade-Tip Vortex Noise Mitigation Traded-Off against Aerodynamic Design for Propellers of Future Electric Aircraft
Journal article, 2022

We study noise generation at the blade tips of propellers designed for future electric aircraft propulsion and, furthermore, analyze the interrelationship between noise mitigation and aerodynamics improvement in terms of propeller geometric designs. Classical propellers with three or six blades and a conceptual propeller with three joined dual-blades are compared to understand the effects of blade tip vortices on the noise generation and aerodynamics. The dual blade of the conceptual propeller is constructed by joining the tips of two sub-blades. These propellers are designed to operate under the same freestream flow conditions and similar electric power consumption. The Improved Delayed Detached Eddy Simulation (IDDES) is adopted for the flow simulation to identify high-resolution time-dependent noise sources around the blade tips. The acoustic computations use a time-domain method based on the convective Ffowcs Williams–Hawkings (FW-H) equation. The thrust of the 3-blade conceptual propeller is 4% larger than the 3-blade classical propeller and 8% more than the 6-blade one, given that they have similar efficiencies. Blade tip vortices are found emitting broadband noise. Since the classical and conceptual 3-blade propellers have different geometries, especially at the blade tips, they introduce deviations in the vortex development. However, the differences are small regarding the broadband noise generation. As compared to the 6-blade classical propeller, both 3-blade propellers produce much larger noise. The reason is that the increased number of blades leads to the reduced strength of tip vortices. The findings indicate that the noise mitigation through the modification of the blade design and number can be traded-off by the changed aerodynamic performance.

tip-vortex noise

FW-H equation

IDDES

blade tip design

electric aircraft

propeller

Author

Huadong Yao

Chalmers, Mechanics and Maritime Sciences (M2), Fluid Dynamics

Zhongjie Huang

Volvo Cars

Lars Davidson

Chalmers, Mechanics and Maritime Sciences (M2), Fluid Dynamics

Jiqiang Niu

Southwest Jiaotong University

Zheng wei Chen

Hong Kong Polytechnic University

Aerospace

22264310 (eISSN)

Vol. 9 12 825

Reduction of Propeller Noise for Future Electrical Aircrafts

Chalmers, 2019-04-01 -- 2021-03-31.

Design of the aerodynamic properties of an electric aircraft

AoA Transport, 2021-01-01 -- 2022-12-31.

AoA Energy, 2021-01-01 -- 2022-12-31.

Areas of Advance

Transport

Energy

Subject Categories

Aerospace Engineering

Vehicle Engineering

Fluid Mechanics and Acoustics

Infrastructure

C3SE (Chalmers Centre for Computational Science and Engineering)

DOI

10.3390/aerospace9120825

More information

Latest update

1/10/2023