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Updated: Jan 5, 2026
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Experimental Investigation of the Flow Structure over a Delta Wing Via Flow Visualization Methods
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Bioinspired aerofoil adaptations: the next steps for theoretical models
1Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA, UK.
Summary
This study introduces a new analytical model for predicting noise from rough aerofoil trailing edges. The model improves accuracy by including edge diffraction, enhancing predictions for porous materials.
Area of Science:
- Aeroacoustics
- Fluid Dynamics
- Aerodynamics
Background:
- Theoretical models for aerofoil noise often disagree with experimental data, particularly for porous trailing edges.
- Existing models neglect surface roughness, a key factor in noise generation from porous materials.
Purpose of the Study:
- To develop an analytical model for predicting far-field noise from rough surfaces at aerofoil trailing edges.
- To improve the accuracy of noise predictions for porous trailing-edge adaptations.
Main Methods:
- An analytical model based on the acoustic analogy was developed.
- The model incorporates diffraction by a sharp edge, unlike previous infinite-wall roughness models.
Main Results:
- The new model shows improved agreement with experimental data compared to models neglecting edge diffraction.
- The findings highlight the importance of surface roughness and edge diffraction in aerofoil noise.
Conclusions:
- The developed model offers a more accurate prediction of far-field noise from rough trailing edges.
- This work can enhance theoretical predictions for noise generated by turbulent interactions with porous trailing edges.
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