ACOUSTIC TOPOLOGY OPTIMIZATION OF A PLATE WITH CONSTRAINED LAYER DAMPING TREATMENT COUPLED WITH A CAVITY

An acoustic topology optimization of the flexible plate with constrained layer damping (CLD) treatment coupled with a rigid acoustic cavity is presented to minimize the sound radiation power. A mathematical model is developed to simulate the sound radiation based on the theories of finite element as well as boundary element theories together. The model is integrated with the acoustic topology optimization approach which adopts the evolutionary structural optimization (ESO) method to search the optimal layout of CLD material on the plate to suppress sound radiation inside the cavity. The sound radiation power and sound pressure at certain modal frequency are considered as the optimal objectives respectively, while the volume fraction of CLD material on the plate is selected as the constraint condition. Numerical results demonstrate the effectiveness of the topology optimal layout of CLD material on the flexible plate to attenuate sound radiation inside the cavity as an available invaluable design tool in engineering. Experimental verification is carried out by manufacturing topology optimized plates and monitoring their sound radiation into a rigid acoustic cavity. The measured sound pressures are found to be in good agreement with the predictions of the mathematical model.