Bliss D., Franzoni L., Danilov P.

In the high frequency limit, a vibrating panel subject to spatially-random temporally-broadband forcing is shown to have broadband power and directivity properties that can expressed analytically by a limited set of parameters. The radiated pressure field power and directivity are characterized in terms of the structural power flow direction, wave speed ratio, panel damping, and dimensionless frequency. The role of boundary conditions at the panel edge is illustrated, as are the effects of other types of forcing. Corresponding behaviors for panels coupled to form a periodic structure are also shown by approximate analytical solutions and numerical simulation. Overall, relatively simple broadband behaviors are revealed. For a single panel the analytical characterization is shown to be particularly straightforward in the high frequency broadband limit. The relationship between radiation and structural power flow is potentially useful in energy-intensity based prediction methods with application to aircraft interior noise prediction.