Sound source localization in closed rectangular duct using an inverse method based on the rectangular waveguide green’s function

Abstract Beamforming (BF) is widely used in aeroacoustics to identify sound sources during wind tunnel testing. However, closed-section wind tunnels create highly reverberant environments due to sound reflections from hard walls, complicating source localization. This paper proposes a novel sound source identification method based on an inverse method utilizing the rectangular waveguide Green’s function. The method is validated through numerical simulations, processing single monopole sources at various frequencies and positions, including scenarios with hard wall reflections. Results show that, compared to the free-field Green’s function, the rectangular waveguide Green’s function more accurately predicts the sound field in the presence of reverberation, providing a solid foundation for the proposed method. Comparative analyses with traditional beamforming demonstrate that the proposed method significantly improves localization accuracy and effectively mitigates the impact of reverberation.