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The overall aircraft noise is significantly minimized using curved light weighted sandwich shells as an airframe element. However, there is a lack of studies on how the curvature can influence vibro-acoustic characteristics. To the best of our knowledge, this paper presents an analytical solution that predicts the vibro-acoustic characteristics of simply supported light-weighted sandwich shells with various curved profiles for the first time. Natural frequencies, displacement and velocity responses, sound pressure level (SPL), sound transmission loss (STL), and radiation efficiency are the critical parameters when analyzing vibro-acoustic characteristics of any structure and are presented in this paper. The generalized kinematic equations are established for the sandwich shells, and the governing differential equations are derived using Hamilton's principle. The solutions are obtained using Navier's method, and the vibration response is determined by solving the first five unknown mode coefficients. The Rayleigh Integral is used to extract the acoustic responses and is validated. In addition, the effect of face sheet to core thickness ratio (h f ∕ h c) of curved sandwich shells on vibro-acoustic characteristics is critically examined and presented. It is found that introducing the positive curvature to the sandwich shell reduces the bending moment, thus improves improving the vibro-acoustic characteristics in the lower frequency range. An increase in the (h f ∕ h c) enhances the shell's vibro-acoustic characteristics until a threshold value (h f ∕ h c = 0. 5) , beyond which the mass contribution deteriorates the characteristics. For a hyperbolic paraboloid shell (h f ∕ h c > 0. 5) , this effect was observed at a lower-frequency value of 425 Hz. [ABSTRACT FROM AUTHOR]

This paper investigates the vibration and acoustic characteristics of an aluminium-silicon carbide (Al-SiC) simply supported composite plate under thermal loads. The vibrational response induced by the temperature rise is analysed using Kirchhoff’s plate theory and the weighted integral (Galerkin) method. Additionally, the plate is acoustically modelled in conjunction with the air medium to investigate its acoustic response. The acoustic far-field radiation equation determines the plate’s sound pressure level (SPL). The findings reveal that the MMC I (65% SiC/A356.2 MMC SiC particulates reinforced, with three different sizes) plate exhibits a lower overall sound pressure level in the lower frequency range than other MMCs. Moreover, replacing the aluminium plate with the MMC I plate reduces the overall sound pressure level by 5.54 dB due to the high stiffness associated with the mixture of silicon carbide reinforcement in the aluminium matrix. [ABSTRACT FROM AUTHOR]