Vibro-Acoustic Formulation of Elastically Restrained Shear Deformable Orthotropic Plates Using a Simple Shear Deformation Theory

Abstract

A method is presented for vibro-acoustic analysis of elastically restrained orthotropic shear deformable plates subjected to excitation forces at different locations. The vibration of the shear deformable plate is formulated on the basis of the Ritz method and a simple first-order shear deformation theory in which 4 rather than 5 displacement components are used to simulate the deformation of the plate. The accuracy of the modal characteristics (natural frequency and mode shape) of an orthotropic plate predicted using the proposed method is verified by those obtained using other methods. The vibration responses of the plate are used in the first Rayleigh integral to construct the sound pressure level (SPL) curves of the plate subjected to excitation forces at different locations. The suitability of the present method for sound radiation analysis is validated by comparing the SPL curve obtained using the present method with those obtained using the other methods. The effects of different system parameters on the SPL curve of the plate are studied by means of several numerical examples. It has been shown that excitation location has significant effects on the smoothness of the SPL curve.

Numerical vibroacoustic analysis of multi-layered composite structure under hygrothermal loading using coupled FEM-IBEM micromechanical model

“…The problem of the acoustic radiation caused by vibrating flat/curved laminated composite shell/shell panel structures into the surroundings has been a topic of critical interest over the past few years. 14 The assessment of the sound radiated into the surrounding by a vibrating structure is typically attained by precisely estimating the fluid-structure interaction via suitable procedures. Amongst the various methodologies currently adopted to solve structural vibroacoustic problems, the boundary element method (BEM) together with the finite element method (FEM) are usually applied for solving the interior and the exterior vibroacoustic problems.…”

Sound Enhancement of Orthotropic Sound Radiation Plates Using Line Loads and Considering Resonance Characteristics

“…When subjected to forced vibration, a plate will radiate sounds that may affect the surrounding environment. Hence, many researchers have proposed different methods to study the sound radiation behavior of plates [22][23][24][25][26][27][28][29][30][31][32][33]. For instance, Lomas and Hayek [26] presented a Green function solution to study the steady-state vibration and sound radiation of elastically restrained rectangular plates.…”

“…With the use of attached point masses, they tried to obtain a uniform distribution of the natural modes to improve the sound response of the plate. Nayan and Kam [31] proposed a SFSDT based Ritz method to analyze the vibro-acoustic behavior of shear deformable sound radiation plates excited by a circular electro-magnetic exciter. Jiang et al [32] used a First-order Shear Deformation Theory (FSDT) based Ritz method to determine the optimal diameter of a centrally located ring load to make a sound radiation plate produce a relatively smooth SPL curve.…”