Dynamic Behavior Analysis of a Shear Deformable Rotating Porous FGM Shaft Using \(p\)-FEM
摘要
This paper presents a comprehensive investigation into the dynamic behavior of rotating Porous Functionally Graded Material (PFGM) shafts using the Timoshenko beam theory, incorporating rotary inertia and gyroscopic effects while undergoing continuous rotation at a constant velocity. Stress–strain relations, along with strain and kinetic energy equations, have been derived to analyze the mechanical behavior under various conditions. A hierarchical beam element formulation discretizes the spinning flexible shaft. The seventh-order shape functions demonstrate stability in the convergence study. Validation against existing literature confirms the accuracy and robustness of the proposed model, using materials such as stainless steel and nickel. A parametric study is performed to illustrate the effects of porosity levels on graded index values, different boundary conditions, and some geometric parameters on natural frequencies. The results reveal that the steady-state natural frequencies decrease with increasing porosity, while for higher FGM indices, they notably increase. Furthermore, boundary conditions significantly affect the vibration behavior. Natural frequencies are analyzed in Campbell’s diagrams to explore the effects of various geometric parameters on PFGM rotating systems such as the thickness ratio