Enhancement of a Free-wake Model by using PIV Measurements for the Study of a Small-scale Propeller with Dissimilar Blade Geometries

This research seeks to improve a free-wake model for the study of the hover performance of a small, two-bladed propeller using the Boundary Element Methodology (BEM), implemented in the medium-fidelity aerodynamic solver RAMSYS, coupled with the tool ACO-FWH for acoustic validation. It emphasises the necessity of accounting for subtle geometric variations, which significantly affect aeroacoustic predictions, specifically sub-harmonic SPL spectra. An optimisation process, employing a Genetic Algorithm, determines optimal parameters for the Bhagwat-Leishman vortex core model, enhancing acoustic signature accuracy beyond geometric correction alone. The findings confirm the effectiveness of a carefully calibrated medium-fidelity approach for capturing the details of the aeroacoustic behaviour of small-scale propellers, contingent on accurate geometric representation and optimised wake modelling parameters.