Experimental contribution analysis of external aeroacoustic noise sources to interior noise of automobile

The contribution analysis of various external aeroacoustic noise sources to interior noise is important, enabling to design an automobile with a low interior noise level. With a new technique, the CD (Cholesky Decomposition), it is proposed to decompose an overall interior noise spectrum into multiple spectra, each representing the contribution of a specific noise source to the interior noise. In order to validate this method, three kinds of experiments were conducted. Furthermore, it is proposed to improve the CD-based contribution analysis method to be integrated with existing exterior microphone arrays in the wind tunnel. This method was validated with an experiment with two speakers.