Extension of Amiet's theory to circular geometry

Area of Science:

• Acoustics and Fluid Dynamics
• Aerodynamic Noise Prediction

Background:

• Predicting aerodynamic broadband noise is crucial for designing efficient and quiet aerodynamic systems.
• Existing models often require complex simulations or lack applicability to specific geometries like thin annuli.

Purpose of the Study:

• To develop and validate two novel analytical methods for predicting aerodynamic broadband noise in thin annuli.
• To extend Amiet's theory for leading-edge noise prediction to trailing-edge noise in a circular geometry.
• To assess the effectiveness of a segmentation model for noise prediction in annuli.

Main Methods:

• Adaptation of Amiet's theory to a circular geometry for leading-edge and trailing-edge noise prediction.
• Development of a segmentation model by dividing the annulus into flat plates analyzed using classical Amiet's theory.
• Comparison of model predictions with existing results, experimental data, and the thin annulus model.

Main Results:

• The leading-edge thin annulus model demonstrated good agreement with established data and experiments.
• The trailing-edge segmentation model showed good agreement with the thin annulus model, validating its predictive capability.
• The leading-edge segmentation model exhibited an offset, consistently underpredicting noise compared to the thin annulus model.

Conclusions:

• The proposed analytical methods offer a cost-effective approach to aerodynamic noise prediction for thin annuli.
• The models are suitable for engineering applications, with inputs derivable from Reynolds-averaged Navier-Stokes simulations.
• Further investigation into geometrical characteristics is recommended for refining noise predictions.