Active control of sound transmission through a double panel partition using volume velocity and a weighted sum of spatial gradient control metrics

In this paper, active control of harmonic sound transmission through an acoustically baffled, rectangular, simply supported double panel partition has been analytically studied. Weighted sum of spatial gradients (WSSG) control metric of the radiating panel is minimized to attenuate multiple acoustic sound radiation modes and the results are compared with the minimization of volume velocity. A piezoceramic actuator (PZT) is attached on one side of the panel surface, and the optimal magnitude and phase of the voltage supplied to the PZT for minimizing WSSG and volume velocity at the error sensor locations are calculated using a simple-gradient based algorithm. Also, acoustic source arrangements are considered in the air cavity simultaneously with the structural control to further attenuate the transmitted sound power. Numerical results of sound power transmission ratio and averaged total kinetic energy of panels indicate that PZT should be placed on the incident panel to minimize the control quantities on the radiating panel. Combined WSSG and cavity control is able to control multiple acoustic radiation modes and the cavity modes and, thereby, accomplishes better attenuation in a wide frequency band.