ANALYTICAL AND NUMERICAL INVESTIGATION OF FREE VIBRATION CHARACTERISTICS IN LIGHTWEIGHT ALUMINIUM FOAM PANELS

This research analyzes the vibration behavior of aluminum foam composite panels, which are increasingly used in lightweight engineering applications such as the aerospace and automotive industries. The conventional Kirchhoff plate theory and the Donghui Xu and Ju-Heng Ju equations were used to calculate Young's modulus of the foam panels, and the accuracy of the results was verified using numerical analysis using ANSYS. The study relied on calculating the natural frequencies of the panels using analytical modeling that integrates conventional plate theory, and these results were then compared with the numerical analysis using ANSYS. Mathematical equations were used to calculate the effects resulting from changes in core thickness, density, and aspect ratio. The results showed that increasing core thickness enhances stiffness and increases natural frequencies while increasing the aspect ratio (a/b) increases elasticity, which reduces frequencies. It was also shown that increasing the aluminum foam density leads to a decrease in natural frequencies. The analytical results for the first natural frequency (m=1, n=1) at a density of 400 kg/m³ and a thickness of 5 mm indicated 275.64 Hz, whereas the numerical results were 273.12 Hz, yielding an error percentage of 0.87%. With a core thickness of 10 mm and a density of 400 kg/m³, the analytical results for the first natural frequency were 456.35 Hz, whereas the numerical results were 447.75 Hz, yielding an error percentage of 1.89%.