Oscillations of the soundabsorbing perforated glass-reinforced plastic and carbon-reinforced plastic panel with system of cells of tubular type

The dynamic behaviour of the sound-absorbing panel from a composite material, consisting of two layers tubular elements of rectangular cross-section is investigated. The problem free and forced oscillations glassreinforced plastic and carbon-reinforced plastic composite panel is solved by method of final elements in view of perforation of the sound-absorbing surface, the applied technique of an estimation of efficiency of a sound absorption on the basis of the data on a spectrum of own frequencies composite construction. For mechanical models of the sound-absorbing perforated panel effect of perforation of a loaded layer and a material of a construction on distribution of a frequency spectrum and forms of oscillations composite construction is investigated.