Computer simulation for high-order stability analysis of a multi-layer disk with honeycomb core under residual stress

Structures in honeycomb shapes have the configuration of a honeycomb to minimize material usage and to reach minimal cost of material and optimized weight. Thereby, this paper investigates the vibrations of sandwich disk which has imperfect honeycomb core with face sheets of graphene nano-platelets reinforced composite (GPLRC). The core of honeycomb is manufactured of aluminum based on to its high stiffness and low density. In order to have an efficient material constant for the layers of composite, this paper considers the modified Halpin-Tsai theory and the mixture rule. The structure's governing equations of motion are extracted and solved using the Hamilton's principle and generalized differential quadrature method (GDQM), respectively. Then, in order to present the impacts of the patterns of FG, the GPLs' weight fraction, thickness ratio of FG face sheet, GPLs' thickness to length ratio, external to internal radius ratio, the honeycomb core's thickness to internal radius ratio, the compressive and tensile external load on the sandwich disk's frequency with FG-GPLRC face sheet and honeycomb core under a uniform pressure, a parametric research study has been carried out. The results show that the lowest and highest frequency is for FG-O and FG-X patterns, respectively. Another consequence is that the when GPLs are wider, the frequency is much higher, particularly at the initial l(GPL)/t(GPL)