CFD analysis of propeller noise

Abstract

This paper presents CFD results for flows around propellers and compares their aerodynamics performance as well as their aero-acoustics. After some validation of the employed CFD method using wind tunnel experiments, a modern propeller design was assessed. Using the same baseline blade, different propellers were put together by adding stagger at the blade hub and small variations of the inter-blade angle. The employed method produced results showing differences in the propeller acoustics regarding the frequency spectrum produced by each design and the level of the acoustic tones. Installed and un-installed blades were also compared and the results show that the wing, nacelle and fuselage of the blades influence the obtained level of noise but not the frequency content. Computations for a climbing case also show the strong effect of the flight conditions on the acoustic results.