An active control strategy for achieving weak radiator structures
- SRI International, Menlo Park, CA (United States). Acoustics and Radar Technology Lab.
- Pennsylvania State Univ., University Park, PA (United States). Center for Acoustics and Vibration
A general control strategy is presented for active suppression of total radiated sound power from harmonically excited structures based on the measurement of their response. Using the measured response of the structure together with knowledge of its structural mobility, and equivalent primary excitation force is found at discrete points along the structure. Using this equivalent primary force and performing a quadratic optimization of the power radiated form the structure, a set of control forces is found at selected points on the structure that results in minimum radiated sound power. A numerical example of this strategy is presented for a simply supported beam in a rigid baffle excited by a harmonic plane wave incident at an oblique angle. A comparison of the response of the beam with and without control forces shows a large reduction in the controlled response displacement magnitude. In addition, as the result of the action of the control forces, the magnitude of the wave number spectrum of the beam's response in the supersonic region is decreased substantially. The effect of the number and location of the actuators on reductions in sound power level is also studied. The actuators located at the anti-nodes of structural modes within the supersonic region together with those located near boundaries are found to be the most effective in controlling the radiation of sound from a structure.
- OSTI ID:
- 5219936
- Journal Information:
- Journal of Vibration, Acoustics, Stress, and Reliability in Design; (United States), Vol. 116:1; ISSN 0739-3717
- Country of Publication:
- United States
- Language:
- English
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