Efficient low-fidelity aeroacoustic permanence calculation of propellers

A noise footprint prediction framework for propeller-driven aircraft which couples an aerodynamic model and several aeroacoustic models is presented in this study. The based on the blade element momentum theory, while are a time-domain compact dipole/monopole Ffowcs-Williams Hawking's acoustic analogy, trailing edge model, hemisphere database approach including straight-ray propagation respectively. In order to reduce runtime, frequency-domain formulation, derived by Hanson (1980), implemented validated against analogy. evaluates effects of variations design operating conditions propeller forward flight. Noise footprints, obtained with different configurations having varying advance ratio number blades compared. It found that, given thrust, drop alters source directivity dramatically, resulting variation up 30 dBA footprint. When kept same increases from 5 7, becomes 16 due change directivity, but maximum level remains same. latter condition reduces loading each blade, consequently associated noise. However, total unchanged as consequence increasing thickness lower ratio, high tip Mach number, addition extra blades.