Active control of sound radiation from rib stiffened plate by using decentralized system

The control of low frequency sound radiation from rib stiffened plate has great practical significance since it is widely applied as aircraft or ship fuselage shells. This paper presents an investigation on the performance of active control of sound radiation from the ribbed plate by using decentralized control system. The theoretical model of the active control system with the decentralized control approach is firstly established. Then, the influences of the number and the arrangement of the decentralized unit on the control performance are specially investigated as an important part. And the influence of the rib on the control effects of the decentralized system is also analyzed. Results obtained demonstrate that, similar with that of the unribbed plate case, appropriately choosing the number of the unit and their feedback gains can achieve good control results. Too many units or very high feedback gains will not further bring more noise reduction. The decentralized feedback loops should also been appropriately arranged so as to achieve good control performance.