Nonlinear free vibration analyses of size-dependent functionally graded annular microplates possessing variable length scale parameter

Download
2023-3-31
MIZRAK, SİNEM
In this thesis study, the nonlinear dynamic behavior of functionally graded (FG) annular microplate is examined. The mechanical properties (i.e., modulus of elasticity, Poisson’s ratio, shear modulus of elasticity, density) of FG plates change continuously and smoothly in the thickness direction. The nonlinearity is caused by von Karman’s large deformation assumption. The boundary conditions are assumed as simply supported and the governing partial differential equations for nonlinear free vibration of a FG annular microplate are presented. The size dependency is taken account by using the Modified Couple Stress Theory (MCST) in the derivation of equations. Hamilton’s principle is utilized to obtain the partial differential equations of motion and boundary conditions. The associated equations are discretized by using Differential Quadrature Method (DQM) and solved by utilizing two different methods, which are strain energy equivalence method and Harmonic Balance Method (HBM). In addition, Rayleigh-Ritz (RR) Method is also utilized to obtain eigenvalue equation instead of DQM. The numerical results for dimensionless natural frequencies are represented. The influence of the length scale effect on numerical results is also investigated.
Citation Formats
S. MIZRAK, “Nonlinear free vibration analyses of size-dependent functionally graded annular microplates possessing variable length scale parameter,” Ph.D. - Doctoral Program, Middle East Technical University, 2023.