Fluid-Structure-Interaction Analysis of an Aero Hydraulic Pipe Considering Friction Coupling

A hydraulic pipe is a basic component of the aero hydraulic system, while high pressure and high speed lead to the enhancement of multiple field coupling effects, such as the structure, fluid, heat, and sound of the aero hydraulic pipe. A larger elastic deformation of the pipe and the more common unsteady flow of fluid can aggravate the vibration and noise of the hydraulic pipe system. Based on the 14-equation model of fluid-structure-interaction (FSI) vibration of aero hydraulic pipe, a model suitable for a wide Reynolds number range is proposed by comparing and analyzing various kinds of friction coupling models. This model is used for the FSI dynamic behavior analysis of aero hydraulic pipes, which improves the accuracy of FSI frequency-domain solutions under high Reynolds number conditions. Second, based on the 14-equation model of FSI vibration of aero hydraulic pipe and the transfer matrix method, the mathematical model of airframe deformation load of an aero hydraulic pipe is established, and the evolution law of the FSI dynamic behavior of the aero hydraulic pipe under different airframe deformation loads is analyzed. All the above analysis results were verified by the experimental analysis. The error of the analysis results of the FSI vibration frequency is smaller than 5% compared with the experimental results. The results show that the proposed method is feasible and effective for predicting the hydrodynamic behavior of the aero hydraulic pipes under load conditions.