Investigation of parallel microperforated panel absorbers under high acoustic excitation

The normal incidence sound absorption of the parallel-arranged microperforated panel absorbers with different backing cavity depths under high acoustic excitation is investigated. A two-dimensional finite element model is established to simulate the acoustic behaviors of the MPP absorber array subjected to high-intensity sound. Under high acoustic excitation, the acoustic energy converts to the vortical energy due to the jet formation at the exit of orifice, and hence, a nonlinear acoustic impedance model is adopted. The MPP absorber array with different designed geometric parameters are studied. Compared with MPP absorber array in linear regime, the numerical results show that the MPP absorber array provides good absorption performance with a wider frequency range in the nonlinear regime. The variation of the acoustic response of the absorber array with different incident pressure is also discussed. Experimental studies are conducted to verify the finite element model of the parallel-arranged MPP absorbers. The prototype is tested under normal incident. The estimated and measured results show good agreement.