Noise and vibration control of composite material plate based on frequency shift using topology optimization

Summary form only given. This paper describes a topology optimization method for a structure to get the best acoustic characteristics, e.g., sound power. The method is applied via shifting the eigenfrequency away from the excitation frequency. Topology optimization design of vibrating composite material elastic plate with respect to minimization of the sound radiation has been studied. Volumetric densities of stiffer material are chosen as design variables. The sound power is expressed as a positive definite quadratic form of the Hermitian, and the sensitivity of the objective function is transformed into the sensitivity of dynamic and impedance matrix. To illustrate the design method, a simple supported thin plate is taken as a simulation example. We have investigated that the sound radiation from structures subjected to forced vibration can be considerably reduced by topology optimization method, leading to a reduction of 20 dB of the sound power.