Wing shielding effect on tonal noise from an electric ducted fan: A numerical and experimental study

To incorporate realistic fan characteristics into acoustic shielding assessment, this paper presents a comprehensive study combining numerical prediction with experimental research. An integrated “hybrid-KABI” prediction framework is developed to address this complex scattering problem. This method enables an end-to-end calculation of the complete physical chain, integrating source generation from unsteady blade loadings, sound propagation within a finite-length duct, and subsequent wing scattering into a unified workflow. To validate this approach, an experimental rig was established to provide high-quality benchmark data. Comparisons demonstrate that the proposed method achieves accurate predictions for both absolute and relative sound pressure levels across various configurations and frequencies. Moreover, the results identify the wing axial position as a critical parameter affecting the total sound field, with significant noise reduction obtained throughout most of the shadow domain. The shielding performance is observed to depend on the local characteristics of the incident sound field. Scattering effects act to redistribute energy from the dominant source lobes to “fill in” the acoustic troughs, thereby causing a noise level increase within these low-magnitude regions. Furthermore, comparisons with a monopole source highlight the necessity of accounting for realistic source characteristics for the rigorous assessment of the shielding effect in practical installation scenarios.