航空液压管路流固耦合振动传递矩阵模型分析

A section of multi-bending hydraulic pipeline of the domestic large aircraft C919 is divided into multiple subsections according to the curved structure, the relationship between the subsections is analyzed based on the currently shared fluidsolid coupling equation-14 for hydraulic pipelines, and a complete dynamical model for transfer matrixes for the section of the pipeline is established by using the transfer matrix method. Then, the system of partial differential equation of the model is solved based on Matlab programming, and the pipeline’s fluidsolid coupling vibration under normal flight vibration load and functional impact load is analyzed, thus the frequency domain response in the axial velocity under three-direction excitation is obtained. The results of the model analysis are verified by experiment. The experiment shows that the respective response frequencies under three directions of excitation are the same, only the amplitudes of the response are different. Furthermore, the vibration amplitude of the pipeline at low-frequency is larger, which indicates that the low frequency vibration is more intense, and which is more likely to trigger resonant failure. The proposed transfer matrix dynamic model and its solution algorithm have high accuracy, and the maximum error is only 4.5%.