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Porous ground treatments for propeller noise reduction in ground effect
Hasan Kamliya Jawahar1, Liam Hanson2, Md Zishan Akhter3
1Department of Aerospace Engineering, University of Bristol, Bristol, BS8 1TR, UK. hasan.kj@bristol.ac.uk.
Scientific Reports
|January 22, 2025
Summary
Porous ground treatments significantly reduce propeller noise in ground effect, enhancing Urban Air Mobility (UAM) system integration. These materials improve acoustic predictability and stability for quieter aerial vehicles.
Area of Science:
- Aerodynamics
- Aeroacoustics
- Materials Science
Background:
- Propeller noise near the ground is a key challenge for Urban Air Mobility (UAM) integration.
- Porous ground surface treatments offer a potential solution for noise reduction.
Purpose of the Study:
- To investigate the effectiveness of porous ground surface treatments in reducing propeller noise.
- To analyze the aerodynamic and aeroacoustic behavior of propellers in ground effect with porous surfaces.
Main Methods:
- Experiments conducted in an anechoic chamber with an APC propeller.
- Utilized a rigid flat plate ground plane treated with various porous foams.
- Measured noise using microphone arrays in near-field and far-field locations.
Main Results:
- Porous surface treatments demonstrated significant noise suppression.
- Coherence analysis indicated improved spatial consistency and predictability of acoustic signals.
- Interaction between propeller wake and porous surfaces enhanced noise reduction and hydrodynamic stability.
Conclusions:
- Porous ground treatments are effective in mitigating propeller noise in ground effect.
- Findings support the development of quieter and more efficient UAM vehicles.
- This research aids in the integration of UAM systems into urban environments.
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