Abstract: The non-uniqueness of sound field solution at corresponding structural internal characteristic frequencies and the high sensitivity of the solution to the point sound source positions exist in virtual point sound source method. A method is proposed to utilize the surface sound sources and point sound sources to model the sound field, thus achieving the uniqueness of solution and the high calculation accuracy in the whole wavenumber domain. According to wave superposition principle, the virtual surface sound sources and point sound sources are simultaneously arranged inside the structure to disperse the sound fields. The surface sound sources are located on a surface conformal to the structural boundary in order to match the sound pressure and vibration velocity of the structural surface. The point sound sources are located inside the virtual surface.A sound radiation impedance matrix was constructed using the linearized Euler equation, and the acoustic parameters of the structure, such as surface sound pressure and vibration velocity, were obtained. Taking pulsating spherical source and transverse vibration spherical source as examples, on the basis of comparing the calculation accuracies of using surface sources and point sources, the accuracy and uniqueness of the proposed method are illustrated by comparing the results with the analytical solutions.

Key words: acousticradiation, wavesuperpositionprinciple, non-uniqueness, virtualsoundsource