Resonant responses and double-parameter multi-pulse chaotic vibrations of graphene platelets reinforced functionally graded rotating composite blade

The applications of the new graphene platelet reinforced functionally graded (GPR-FG) composite materials are helpful to improve the overall performance of the rotating blade. However, the new GPR-FG rotating composite blade may produce the strong nonlinear vibrations under the coupling effects of the aerodynamic force and disturbed speed, which are one of the main reasons leading to the overall failure of the rotating blade. Therefore, it is of great value to analyze the nonlinear dynamics of the GPR-FG rotating composite blade under the aerodynamic force and varying speed. Based on the nonlinear dynamic model of the GPR-FG rotating composite blade, the resonant responses, global bifurcations and double-parameter multi-pulse chaotic vibrations of the rotating composite blade are studied for the first time. The prediction-correction continuation algorithm is used to obtain the amplitude-frequency response curves and force-amplitude curves of the GPR-FG rotating composite blade. It is found that there are the sudden changes in the resonant responses and complex nonlinear vibrations in the GPR-FG rotating composite blade. The extended Melnikov method is applied to study the global bifurcations and double-parameter multi-pulse chaotic vibrations of the GPR-FG rotating composite blade under the coupling excitations of aerodynamic force and disturbed speed. Through theoretical analysis and numerical simulation, we find that there are the complex double-parameter multi-pulse chaotic vibrations of the GPR-FG rotating composite blade. These results have the theoretical significance for the safe operation of the new GPR-FG rotating composite blade. (c) 2022 Elsevier Ltd. All rights reserved.