A comparative study of recorded and computed sounds radiated by vibrating plates
Résumé
This study concerns the auditory properties of sounds radiated by a fluid-loaded vibrating plate excited by a transient point force. It is related to the field of psychomechanics, which is a combination of vibroacoustics and psychoacoustics. The object of psychomechanics is to establish correlations between the mechanical parameters of a vibrating structure, the acoustic field generated by its vibrations and the auditory attributes of the corresponding sounds. The particular aim of the present study is to estimate the validity of a model designed to simulate the acoustical radiation of a vibrating plate. The model is based on the development of resonance modes. We consider the case of a clamped plate excited by an impact hammer. Vibroacoustic measurements were done, in an anechoic chamber (excitation, acceleration of the plate and acoustic pressure); they provide the entry data for our model. Next, dissimilarities between recorded and synthesized sounds were evaluated from a physical (temporal and spectral) point of view. Further dissimilarity tests were run to determine how many modes have to be taken into account in the calculations, an important issue in terms of computation time.