Analytical prediction of broadband noise from mini-RPA propellers with serrated edges

This paper is dedicated to the analysis of the broadband noise of an innovative mini-remotely piloted aircraft propeller geometry with straight or serrated edges. New analytical models for predicting the trailing/leading edges noise from airfoils with serrated edges are implemented and applied to propellers using a blade strip approach. These models are assessed by comparison with spectra obtained from time-domain Lattice Boltzmann method simulations. Obtained results showed that the analytical models are able to predict the noise from either straight or serrated propellers with a good accuracy. A parametric study was conducted to predict the noise emitted by propellers featuring sawtooth trailing edge or leading edge serrations with different parameters. It is shown that the best performance in terms of noise reduction is achieved by sharp and deep serrations. The effects of flow conditions on the noise emitted by the serrated propellers are also investigated.