基于流-固耦合的车辆减振器动态非线性仿真分析

Simulation analysis of dynamic nonlinear characteristics of vehicle shock absorber based on fluid-structure interaction

基于流-固耦合有限元方法,利用ADINA软件建立了高精度的叠加节流阀片有限元网格模型和流场有限元网格模型,并在ADINA软件后处理模块中进行求解分析,得到了减振器阻尼力-速度分段特性、示功特性、阀系内部的压力场和速度场特性,分析了减振器阀系动态非线性特性。结果表明:在高速减振器油的冲击下,阀系内部区域的压力场变化明显;达到开阀压力时,油液流动速度呈现跳跃变化,使得阻尼通道压力迅速变化。这说明叠加节流阀片有限元网格模型和流场有限元网格模型的精度对仿真结果影响最大。在流-固耦合计算中考虑了流体湍流流动、阀片接触和大位移变形,尽量使仿真模型与物理模型保持一致,试验结果与仿真结果吻合较好。

Using software ADINA, accurate finite element mesh models of the superposition throttle slice and fluid field are established based on the Fluid-Structure Interaction （FSI） method. The velocity property, the indicator diagram, internal pressure field and velocity field of the shock absorber are obtained using the post-processing module of ADINA. The nonlinear dynamic characteristics are analyzed. Results show that, under high-speed impact of the shock absorber oil, the pressure field inside the valves changes significantly. When reaching the valve-opening pressure, the fluid velocity suddenly jumps, making the pressure change rapidly in the damping channel. The finite element mesh models of the superposition throttle slice and fluid field significantly influence the accuracy of the simulation results. The FSI model is close to the physical reality because the consideration of the turbulent flow of oil, the contact slip and large deflection of the throttle slices. The simulation results are in good agreement with the experimental results.