Computer simulation as an aid to predict fundamental frequency of a sandwich system via discrete singular convolution method

Abstract

Present article is the first attempt to analyze the vibration behavior of the composite sandwich cylindrical panels based on the integration of a statistical approaches with numerical solver of differential equations. The motion equations of the structure with functionally graded graphene-platelets reinforced composite (FG-GPLRC) face-sheets imbedded in linear and torsional spring-simulated elastic substrate and subjected to multi-orientational initial stresses are formulated based upon three-dimensional poroelasticity theory. Bi-directional discrete singular convolution method (DSCM) is implemented to find the natural frequency of the mentioned system at design-points. Then, the response surface method is utilized to acquire the closed form of the natural frequency and predict the vibration response of the system according to the reduced third-order polynomial functions. The modified format of Halpin-Tsai micromechanics is employed in order to approximate the elastic properties of the structure. The veracity of the solving procedure is verified by comparing its outcomes with those recorded by the high-quality literature. The results reveal that the span-angle of the panel plays the most important role in the free vibration response of the system compared with the other parameters whose effects are studied in this article. Additionally, it is concluded that reinforcing the face-layers of the sandwich panel by graphene-platelets (GPL) is the more effective way to increase the stiffness of the sandwich structure compared with the case of reinforcing the core section.