Dynamic Model and Response Analysis of Bionic Hydraulic Pipeline Based on Vascular Physiological Structure

A bionic hydraulic pipeline (BHP) with a three-layer structure is designed innovatively on the basis of an animal's biological mechanism. Its intermediate layer is rubber material and the middle layer is the same as the middle layer of the blood vessels at the outlet of a cheetah's heart and has good viscoelasticity. This is used to absorb the flow pressure pulsation of the hydraulic system. Besides, a dynamic model of a BHP and the effect of absorption pulsation are further studied. It includes a rubber material model and the FSI (fluid-structure interaction) dynamic equation of the relationship between the liquid and rubber material. For rubber materials, the Mooney-Rivlin model is selected to describe the dynamic characteristics. After testing the stress and strain data through experiments, C10 and C01 of the rubber material are obtained. After determining the constitutive model of rubber and its parameters, the FSI model of the BHP is established. The natural frequency of the BHP is obtained when we solve the model with Matlab. Furthermore, to evaluate the accuracy of the model, hammer mode experiments are performed. They show that the accuracy of the model's evaluation is within 5%. On this basis, the length and thickness of the rubber layer and the pressure of the flow in the pipeline are changed. The vibration of the pipeline is analyzed and utilized by ANSYS. On the experimental rig, a BHP with different lengths and thicknesses of silicon film was manufactured and installed at the high-pressure outlet of the axial piston pump, and then the vibration of the outer wall of the pipeline was tested. The results show that the BHP has an obvious absorption effect on the flow pulsation of the axial piston pump outlet.