Faculty Publications

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  • Item
    Vibro-acoustics response of an isotropic plate under non-uniform edge loading: An analytical investigation
    (Elsevier Masson SAS 62 rue Camille Desmoulins Issy les Moulineaux Cedex 92442, 2020) Gunasekaran, V.; Jeyaraj, J.; Mailan Chinnapandi, L.B.M.
    Analytical studies carried out on the vibro-acoustic response behavior of an isotropic plate under non-uniform edge loads subjected to steady-state mechanical excitation is presented. An analytical method based on the energy approach is used to calculate the buckling load (Pcr). Free and forced vibration responses of the plate are obtained using an analytical method based on Reddy's third-order shear deformation theorem (TSDT) while sound radiation behavior is analyzed using Rayleigh Integral. Results revealed that Pcr is significantly influenced by the nature of non-uniform edge load. Similarly, natural frequencies reduce with an increase in axial compressive load due to a reduction in structural stiffness. Vibration and acoustic resonant amplitudes are affected by the intensity of the compressive load. Sound transmission loss reduces with an increase in compressive load magnitude and the effect is significant in the stiffness dominant region. © 2020 Elsevier Masson SAS
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    Acoustic response behavior of porous 3D graphene foam plate
    (Elsevier Ltd, 2020) Kumar, A.; Gunasekaran, V.; Mailan Chinnapandi, L.B.M.; Jeyaraj, J.
    Sound radiation and sound transmission loss (STL) behavior of porous 3D graphene (3D-GrF) foam plate are presented. Two variable refined plate theory which includes both transverse bending and shear stresses is used to model the plate and Navier's solution is used to calculate the vibration responses while Rayleigh integral is used to analyze the acoustic response. Variation in free vibration frequencies with the nature of porosity distribution is significant for the 3D-GrF plates having higher porosity co-efficient. The natural frequency of the 3D-GrF plate with more porosity around the center and less porosity at the outer surfaces is high. However, resonant amplitudes of the responses and STL of the plates are controlled by both the nature of the porosity distribution pattern and porosity co-efficient. In general, STL of the plate with less porosity around the center and high porosity at the extreme surfaces is high compared to the other cases. © 2020 Elsevier Ltd
  • Item
    Acoustic radiation and transmission loss of FG-Graphene composite plate under nonuniform edge loading
    (Elsevier Ltd, 2021) Gunasekaran, V.; Jeyaraj, J.; Mailan Chinnapandi, L.B.
    The influence of nonuniform edge loads on the acoustic response of a functionally graded graphene reinforced composite plate is investigated analytically. The energy method is implemented to calculate the buckling load (Pcr). An analytical method based on Reddy's third-order shear deformation theorem is used to obtain the vibration response, and acoustic response is obtained using Rayleigh Integral. The nature of edge load variation on buckling and vibro-acoustic response is significant. Free vibration mode shape changes with an increase in edge load and consequently affects the resonant amplitude of responses also especially for the plates with a higher aspect ratio. Volume fraction and dispersion pattern of graphene nano-platelets also influences the resonance amplitudes. Plate with FG?GRCC dispersion pattern has improved buckling and vibro-acoustic response behavior. Similarly, change in sound transmission loss level is significant in the stiffness region compared to the damping and mass dominated region. © 2021 Elsevier Masson SAS
  • Item
    Structural-Acoustic Response Analysis of Variable Stiffness Laminates with Inherent Material Damping
    (World Scientific, 2022) Gunasekaran, V.; Gulhane, S.; Gupta, S.; Jeyaraj, J.; Vasudevan, V.; Manickam, G.
    Sound radiation and transmission loss characteristics of variable stiffness composite plate reinforced with the curvilinear fibers are investigated numerically. The formulation is developed using higher-order shear flexible finite element model combined with Helmholtz wave equation. The governing equations obtained using Hamilton's approach are further solved through the modal super position method to analyze the vibration response under steady state excitation. The inherent material damping of the laminate is accounted through the modal damping calculated using the modal strain energy approach. The acoustic pressure of the variable stiffness laminates is estimated using the Raleigh integral. Subsequently, acoustic response characteristics such as acoustic power level, radiation efficiency, directivity pattern, and transmission loss from the laminates are predicted using the estimated sound pressure for various forcing frequencies. A parametric study covering a wide range of design variables including center and edge fiber angles, lamination scheme, thickness ratio, and boundary conditions on the acoustic sound behavior arising from the vibration of curvilinear fiber composite plate is detailed. This study reveals that the acoustic response of the curvilinear fiber composite plate is significantly influenced by the curvilinear fiber angles at the center/edge fiber angle of the layers. It is hoped that the results obtained here will be useful for designers in developing structures with desired acoustic response characteristics. © 2022 World Scientific Publishing Company.