Numerical Modeling of the Influence of the Relative Positions of a Propeller and Pylon on Turboprop Aircraft Noise

Resumo

The influence of the position of the pylon on the characteristics of propeller noise has been studied as applied to environmental noise calculations for future aircraft. Components related to propeller noise itself and to a signal reflected from a pylon have been separated in the overall noise produced by the propeller–pylon system at the blade passing frequency, and the interference of these signals has been investigated. A numerical method has been developed based on matching of the following two computational blocks: a rotating domain in the immediate vicinity of the propeller and the outer static domain comprising the pylon. A noise calculation procedure by the integral Ffowcs Williams and Hawkings method has been implemented with the use of the Green’s function for the convective wave equation.