Active Control of the Structural and Acoustic Responses of a Fluid-Loaded Plate;Part II: Feedforward control

Abstract

Attenuation of the structural and acoustic fields associated with a fluid-loaded plate can be achieved with the application of active control to the vibrating structure. For a heavily fluid-loaded structure, the fluid-structure interaction will significantly affect the wave propagation in the structure, as well as the nature of-the sound radiation from the structure into the fluid field. In this paper, two active control systems are applied to the plate to attenuate the structural and acoustic responses. An active structural acoustic control (ASAC) system is designed using feedforward techniques to attenuate the far-field radiating sound power and local sound pressure. Feedforward control laws are also developed for the minimisation of the plate vibration. Under both heavy and light fluid-loading conditions, the performances of the active control systems are examined by comparing the uncontrolled and controlled sound power, sound pressure and plate vibration. The nature of the fluid-loading on the performance of the control systems is also investigated.

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References

Nayak

P.R.

, “Line Admittance of Infinite Isotropic Fluid-Loaded Plates”, J. Acoust. Soc. Am. Vol. 47, 191-201 (1970).

Maidanik

and Kerwin

E.M

Jr , “Influence of Fluid-Loading on the Radiation from Infinite Plates below the Critical Frequency”, J. Acoust. Soc. Am. Vol. 40, 1034-1038 (1966).

Crighton

D.G.

, “The 1988 Rayleigh Medal Lecture: Fluid Loading - The Interaction between Sound and Vibration”, J. Sound. Vib. Vol. 133(1), 1-27 (1989).

Pan

, Snyder

S. D.

, Hansen

C.H.

and Fuller

C.R

, “Active control of far-field radiated by a rectangular panel - A general analysis”, J. Acoust. Soc. Am. Vol. 91(4), 2056-2066 (1992).

and Fuller

C.R.

, “Active control of sound radiation due to subsonic wave scattering from discontinuities on fluid loaded plates, I: Far-field pressure”, J. Acoust. Soc. Am. Vol. 90, 2020-2026 (1991).

and Fuller

C.R.

, “Active control of sound radiation from a fluid-loaded rectangular uniform plate “, J. Acoust. Soc. Am. Vol. 93(1), 337-345 (1993).

Nelson

P.A.

, Curtis

A.R.D.

, Elliott

S.J.

and Bullmore

A.J.

, “The Minimum Power Output of Free Field Point Sources and the Active Control of Sound”, J. Sound. Vib. Vol. 116(3), 397-414 (1987).

Kessissogiou

and Pan

, “Active Control of the Structural and Acoustic Responses of a Fluid-Loaded Plate; Part 1: Analysis of the physical system”, J. Noise Vib. & Active Control Vol. 17 No. 1 1998.

9 Junger

M.C.

and Feit

, Sound Structures and their Interaction (MIT Press, Cambridge, MA, 1986), pp. 52-54, 92, 95-97.