ACOUSTIC RADIATION DAMPING OF FLAT RECTANGULAR PLATES SUBJECTED TO SUBSONIC FLOWS. PART II: COMPOSITE

The acoustic radiation damping for various plates and semi-infinite strips subjected to a uniform, subsonic and steady flow has been predicted. The predictions are based on the linear vibration of a flat plate. The fluid loading is characterized as the perturbation pressure derived from the linearized Bernoulli and continuity equations. Parameters varied in the analysis include Mach number, mode number and plate size, aspect ratio and mass. Results show that the fluid loading can significantly affect realistic plate responses. In addition, acoustic radiation damping values can be greater than or equal to the structural component of the modal critical damping ratio (assumed as 0·01) for the higher subsonic Mach numbers.

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