Elastic Limit Angular Velocity and Acceleration Investigation in Non-‎Uniform Rotating Disk under Time-Dependent Mechanical Loading

Document Type : Research Paper

Author

Department of Mechanical Engineering, Faculty of engineering, University of Bojnord, Bojnord, P. O. Box 94531-55111, Iran

Abstract

An analytical effort is made to achieve cognition on the effect of time-dependent mechanical loading on the stress fields of rotating disks with non-uniform thickness and density. At high variable angular velocities and accelerations, evaluation of the effect of shear stress on the values of von Mises stress is significant and it is excellent to consider shear stress in this equivalent stress calculation alongside the radial and tangential stress. In the proposed analytical model, the Homotopy perturbation method (HPM) solves the general structure of rotating disks equilibrium equations in both radial and tangential directions. HPM is an efficient tool to solve linear and nonlinear equations, providing solutions in quick converging series. The results obtained through this process are then confirmed using the finite difference method and the exact solution in the literature. The effect of parameters in angular velocity and acceleration functions with the parameter in the thickness function and the effect of boundary conditions on the values of elastic limit angular velocity and acceleration are established by performing numerical examples. Furthermore, the effect of shear stress on the maximum values of von Mises stress is discussed. It is shown that shear stress has more influence on the distribution of equivalent von Mises stress in the elastic region. It is shown the introduced analytical model is useful for evaluating rotating disk with any arbitrary shape of thickness and density function, without using the commercial finite element simulation software.

Keywords

Main Subjects

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