An isogeometric modeling and vibro-acoustic characteristics analysis of a double panel-acoustic cavity coupling system with in-plane functionally graded materials

This study introduces vibro-acoustic modeling for a double panel-acoustic cavity coupling system with in-plane functionally graded materials (FGMs). Based on the excellent ability of isogeometric analysis (IGA) to conduct high-precision engineering analysis and model complex geometric shapes, the IGA is adopted to model an acoustic structure coupling system that combines rectangular or elliptical panels with acoustic cavities. By applying the mixture rule, functionally graded panels are endowed with effective material properties that demonstrate functional variation along the in-plane direction. The governing equations of the system are derived using classical thin plate theory combined with graded IGA panel elements. Numerical analyses assess the convergence and accuracy of the proposed vibro-acoustic modeling. The influence of material and geometric parameters on the panel-acoustic cavity coupling system frequency and modal shapes is investigated. Additionally, harmonic response analysis concerning the velocity and sound pressure is conducted. Both the power-law parameters and the depth of the acoustic cavity impact the natural frequency and the harmonic response of the system are investigated. This study will provide a reference for the application design of in-plane FGMs in double panel-cavity coupling systems.