Near-field acoustic holography for acoustic noise source identification in turbomachinery

A novel approach using basis expansions of acoustic sources is proposed to better condition the inverse problem in NAH. Results indicate that the basis expansion representation of sources provides better source reconstruction results through effectively combating ill-posedness of the inverse problem. The source reconstruction accuracy in direct inversion increases if the measurement data is smoothed prior to inversion. The effects of employing basis expansion technique on denoised/smoothed data will be studied in future.