Sound Radiation of Clamped Multilayered Functionally Graded Plates Considering Physical Neutral Surface

This paper dedicates an analytical computation of vibration and far-field sound radiation of clamped power law index functionally graded plates (P-FGM). This paper deals with uncoupled acoustics and entails a novel approach to computing the natural frequencies, harmonic response, and acoustic response by considering the clamped FGM plate’s physical neutral surface. This work is novel as little research on sound radiation has been carried out using a physical neutral surface. A novel approach of applying surface or nodal velocity (considering all substeps) of the structure as a boundary condition to the acoustic interface is discussed. Four cases segregated on the power law index, n = 0, 1, 5, and 10, have been studied in this research. A more significant frequency substeps are taken to avoid missing any modal contribution in modal and harmonic response analysis. The harmonic displacement response of vibrating clamped FGM plates is calculated analytically in Matlab and fed as an input to the Rayleigh integral code based on Gaussian quadrature to compute the sound radiation fields. The sound radiation field calculated is validated using solid layer-wise modeling using Ansys. It is found that sound radiated by both the methods and results in the literature is in good agreement. It is also found that sound power level increases and radiation efficiency decreases with an increase in the power law index. Thus, it is concluded that clamped mono-ceramic FGM plates act as a good sound radiator.