Numerical Study of Vibro-Acoustic Responses of Un-Baffled Multi-Layered Composite Structure under Various End Conditions and Experimental Validation

Abstract

This article presents the vibro-acoustic modeling and analysis of un-baffled laminated composite flat panels subjected to harmonic point load under various support conditions. The frequency values of the panel are obtained by using simulation model through the commercial finite element package (ANSYS) via batch input technique. Initially, the rate of convergence of the current simulation results is established by solving different examples under various edge supports. Further, the natural frequencies and corresponding modes are computed and compared with available published and experimentally obtained values. Then, the modal values are exported to LMS Virtual.Lab environment for the computation of acoustic responses of the vibrating laminated plate structure. Further, an indirect boundary element approach has been adopted to extract the coupled vibro-acoustic responses. Subsequently, the radiated sound power of the structure and the sound pressure level within the acoustic medium are computed using the present scheme and compared with the published numerical results and in-house experimental data, respectively. Finally, a comprehensive study has been performed to highlight the effect of different structural parameters (thickness ratio, aspect ratio, modular ratio and lay-up scheme), support conditions and the composite properties on the acoustic radiation responses of the laminated plate structure.

Sound Radiation of Orthogonal Antisymmetric Composite Laminates Embedded with Pre-Strained SMA Wires in Thermal Environment

“…As shown in Figure 4 , the calculated result has an excellent agreement with Sharma et al [ 20 ]. Thus, the present analytical method was a sound choice for the study.…”

“…As can be seen from Table 2 , the comparison certifies the correctness of natural frequencies that was calculated by the present method. The second example is sound radiation from antisymmetric cross-ply [0 /90 ] 2 laminated composite flat panel (0.5 m × 0.5 m × 0.02 m) subjected to unit harmonic point load at x = 0.125 m and y = 0.125 m which is taken from Sharma et al [ 20 ]. Table 3 represents the material properties of the graphite-epoxy and glass-epoxy.…”

“…The design of material and structure parameters is an important means to improve the acoustic radiation. Comparing and analyzing sound radiation from material parameters of laminates, the conspicuousness of material composition on response, and the coupling effect of material proportion on sound radiation is often of great significance [ 19 , 20 , 21 ]. In terms of structural parameters, the research on sound radiation has developed from the design of normal geometrical parameters (aspect ratio, thickness) of laminates to more complex structural forms such as periodically reinforced structures and non-uniform laying [ 22 , 23 , 24 , 25 ].…”

Multiphysical theoretical prediction and experimental verification of vibroacoustic responses of fruit fiber‐reinforced polymeric composite

“…[37] The coupled finite element/boundary element (FE/BE) formulation is widely used for solving vibroacoustic problems in the low-frequency range. [38,39] The experimental and numerical sound radiation responses have been evaluated for the laminated composite [40] and layered composite [41] including temperature effect. Similarly, the zig-zag shell theory in the framework of the HSDT type of mid-plane kinematics has been implemented to investigate the acoustic responses of the multi-layered shell structure with arbitrary curvature through Helmholtz integral formulation.…”

Numerical analysis of acoustic radiation properties of laminated composite flat panel in thermal environment: A higher-order finite-boundary element approach

“…Obtaining the vibration behavior of the structure using finite element method (FEM) and subsequently evaluating the acoustic radiation responses via Rayleigh’s integral 24,25 is a traditional scheme. The influence of support conditions 26 and type of mechanical loading 27,28 on the sound radiation characteristics of the isotropic, orthotropic 29,30 plate, thick annular discs, 31 and shell panels 32 have been analyzed from time to time. Further, theoretical studies together with experimentation have also been performed to analyze the vibration and sound radiation characteristics of laminated composite structures and the merits of using coupled FEM–boundary element method (BEM) approach have been demonstrated.…”