Flap wise bending vibration and dynamic stability of rotating functionally graded material plates in thermal environments

摘要

This paper deals with the study of the flapwise bending vibration and dynamic stability of rotating functionally graded material plates in thermal environments. A finite element formulation is derived for modal and dynamic stability analyses of rotating functionally graded material plates using first-order shear deformation theory. Temperature-dependent material properties of the plates are considered in the analysis and a simple power law is assumed for composition of constituent materials to vary along the thickness direction. The same power law is also proposed in thermal environments for temperature variation across the thickness of the plate. Some numerical results obtained from the present method are compared with numerical results available in the literature and are found to be in good agreement. Parametric investigation is carried out thoroughly to study the effect of the temperature rise, hub radius, and rotational speed on vibration and the dynamic stability of rotating plate in thermal environment. Bolotin's method is used to generate the boundaries of stability and instability regions. These instability regions are plotted in the parameter space with the nondimensional dynamic load and excitation frequency. It is observed that the natural frequencies reduce with an increase in temperature rise. Increase in rotational speed and hub radius results in increase of natural frequencies of vibration. The rise in temperature leads to reduction in the dynamic stability of plate. Increase in rotational speed and hub radius enhances the dynamic stability of the rotating plate.