| Abstract:In order to study the vibration characteristics of high pressure tubing in common rail system under fluid-structure coupling, a finite element model of high pressure tubing was established. Firstly, according to the dynamic equation of the infusion pipeline, the wet mode characteristics of the pipeline with additional fluid mass were analyzed by ANSYS software. Then, root-mean-square was used to quantify the vibration energy in the time history, and the vibration response of different elbows of the pipeline under fluid-structure coupling, the influence of different fuel pulsation rate, pressure and excitation frequency on the pipeline's fluid-induced vibration was studied. Finally, the vibration characteristics of the pipeline before and after adding pipe clamps under resonance frequency were compared. The results show that the natural frequency of the pipeline decreases under the fluid-structure coupling, and the decrease rate is more obvious in the high order mode, and the additional mass coefficient exceeds 0.13. The vibration of different elbows varies greatly. The vibration energy is positively correlated with the fuel pulsation rate, but not directly related to the pressure. When the pipeline is close to the natural vibration frequency, the resonance occurs, and the amplitude increases sharply to exceed the standard. After adding the clamp, the resonance phenomenon disappeared and the vibration energy decreased by more than 90%. |