The effect of the acoustic properties of the environment on vibration of a flat plate subject to direct excitation and to excitation by vortex shedding in an airstream
The paper presents the results of an experimental investigation of the vibration of a flat steel plate when excited by a magnetic vibration transducer and by wake shedding due to air flow over the plate. In both cases it was found that the acoustic properties of the space surrounding the plate, in particular the acoustic resonant frequencies, had a very marked influence on the amplitude of vibration and a small influence on the resonant frequencies. The effects included variation of the plate response to a given excitation and variation of the magnitude of the exciting forces due to wake shedding. Qualitative explanations of the phenomena are deduced with the aid of numerical solutions for the acoustic field with the plate vibrating.