Numerical eigenfrequency and experimental verification of variable cutout (square/rectangular) borne layered glass/epoxy flat/curved panel structure

The variation of modal responses due to the change in shapes (square/rectangular) and sizes of the cutout impregnated composite panels (Glass/Epoxy) are predicted numerically using higher-order finite element formulation. The degree of accuracy of the proposed model is verified by comparing the modal values with the experimentally recorded data for the validation purpose, including the experimental composite properties. The isoparametric finite element formulation is adopted to model the layered panel configuration in association with the higher-order polynomial kinematic model. The modeling of the cutout is achieved through the equations of one-quarter of the plate and extended further to join for all four quarters. The model generosity is checked through analyzing the frequencies for variable geometrical shapes (plate, cylindrical, spherical, hyperboloid and elliptical), material properties and boundary conditions. Also, the results are verified for the variable cutout shapes (square and rectangular) and the sizes by comparing the results with published numerical modal values. This is the maiden experimental verification to show the inevitability of higher-order numerical model for the computation of eigenvalues of the laminated composite components with cutout. Lastly, the conclusions are deliberating the effect either individual or the combined design-dependent structural parameters (aspect ratios, thickness ratios, curvature ratios and different end boundary constraints including the sizes of cutout) by solving different examples.

Automated summary

This study predicts the modal responses of cutout impregnated composite panels using a higher-order finite element formulation. The accuracy of the proposed model is verified by comparing it with experimental data. The study also examines the effects of different geometrical shapes and cutout sizes on the modal responses.