Simultaneous structural-control optimization of coupled structural-acoustic system

Simultaneous structural-control optimization of a coupled structural-acoustic enclosure is investigated in this paper. The whole system has a rectangular parallelepiped sound field of which the entire bottom face and the partial top face are covered with two elastic plates while others are enclosed with rigid walls. Two point forces applied on the plates are used as disturbance and control input respectively. In the sound field, a sound sensor is placed to measure the sound pressure output. A feedback H-infinity controller is used to generate the control input signal to reduce the noise at the sensor spot. The coupled structural-acoustic enclosure is modeled by finite element method. The element thickness parameters of the top elastic plate along With the control parameters are optimized simultaneously to reduce the closed-loop H-infinity norm. Numerical results show that the system performance is improved significantly by the simultaneous optimization.