Dynamic Modeling and Vibration Characteristics of Rotating Composite Laminated Beams with Erosion-Induced Cracks

To address the issue of flight safety for aircraft in harsh environments such as sandstorms, the erosion-induced cracking of composite blade of turboprop aircraft and helicopter rotors operating was analyzed in severe wind-sand environments. First, the full-scale blade erosion damage simulations are conducted using ANSYS Fluent software. Simulations were performed under pitch angles of 45 and 60, and rotational speeds of 500 rpm and 1000 rpm, revealing the distribution of erosion damage and stress characteristics of the blades. Then, the damaged blade was simplified as a rotating composite laminated beam model and a dynamic model for the rotating composite laminated beam with single/double cracks was established by integrating the First-order Shear Deformation Theory (FSDT) and Hamiltons principle. Finally, the effects of key parameters-including crack depth, crack location, rotational speed, and pitch angle-on the system's free vibration characteristics and motion stability were systematically investigated. Results indicated that increased crack depth, crack locations closer to the blade root, higher rotational speeds, and larger pitch angles alter the blade's vibration characteristics and reduce system stability. It can provide theoretical support for the erosion-resistant design, early crack diagnosis, and structural stability assessment of turboprop aircraft and helicopter rotor blades.