Flow-induced structural acoustics involves the study of the vibration of a structure induced by a fluid flow as well as the resulting sound generated and radiated by the motion of the structure. A thin rectangular, structure, non-fluid-loaded was excited by turbulent boundary layer flow. A method called magnitude-phase identification (MPI) is derived to measure modal information from a structure using only two-point measurements. Using MPI, the mode shapes and the auto-spectral density of vibration of each mode was measured and found to agree well with the theoretical values. When the non-fluid-loaded structure was excited with a spatially non-homogeneous wall pressure field or fluid-loaded structure was excited with a spatially homogeneous wall pressure field, the measured mode shapes were found to be the same as those predicted by theory. When a fluid-loaded structure was excited with a spatially non-homogeneous wall pressure field, the mode shapes were found to change. This suggests that standard modal analysis may not be sufficient to predict the vibration of fluid-loaded structures, as such theory assumes that the mode shapes of the structure are independent of the method by which the structure is excited.

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