A COMPACT MATRIX FORMULATION USING THE IMPEDANCE AND MOBILITY APPROACH FOR THE ANALYSIS OF STRUCTURAL-ACOUSTIC SYSTEMS

Abstract This paper describes a compact matrix formulation for the steady-state analysis of structural-acoustic systems. A new approach to the problem is adopted that uses impedance and mobility methods commonly found in the analysis of purely structural or purely acoustic systems. The advantages of the approach are that an investigation into the coupling between the structural and acoustic systems is made easier, and it facilitates improved physical insight into the behaviour of structural-acoustic systems. In addition, because the equations describing the complete system are in matrix form, they can be solved easily using a computer. Due to the mismatch of dimensions between structural mobility and acoustic impedance, new terms are introduced for the coupled system analysis; the coupled acoustic impedance and the coupled structural mobility.F-u(force-velocity) andp-Q(pressure-source strength) diagrams are also introduced for impedance and mobility representations of a complete coupled system. Experimental work is presented, in which a simple rectangular acoustic enclosure with five rigid and one flexible side was used, to validate the analytical model and to investigate structural-acoustic coupling.