Study of the influence factors on the accuracy of sound field reconstruction based on wave superposition method

Wave superposition method is a numerical method for sound field reconstruction, which can be applied in sound source identification and fault diagnosis. This study aims to obtain some guidelines to increase the reconstruction accuracy. A number of influence factors are analyzed through theoretical analysis and numerical simulation, including equivalent sources, measurement array, reconstruction distance and regularization methods. Results show that the distribution of the equivalent sources has a great impact on the reconstruction accuracy. The equivalent sources should be collocated interior to the radiator. It's better that the equivalent source surface conforms to the radiator's surface, while the measurement array doesn't need to be conformal to the radiator's surface. Relatively, the reconstruction distance has a little influence on the reconstruction accuracy. At last, four different regularization methods together with two regularization parameter selection approaches are combined with wave superposition method to solve the ill-posed problem. Comparative results indicate that Tikhonov and truncate singular value decomposition regularization methods work well with wave superposition method. In sum, these conclusions are useful to get higher reconstruction accuracy and consequently help wave superposition method become an effective fault diagnosis tool.