铁道车辆油压减振器三维流场动态仿真

Dynamic Simulation of 3D Flow Field of Train Damper

液压减振器是轨道车辆行走部的重要装置,其阻尼特性由一组特殊结构的阻尼阀来实现。为优化液压减振器缸体的整体流道结构,分析关键阻尼阀在不同开启状态下局部流场对阻尼特性的影响,有必要采用流体三维动态仿真计算方法预估其性能。研究中针对某典型轨道机车垂向减振器的结构和参数,构建相应的数学模型和实体模型。采用CFX自适应动网格技术,对各典型振动条件下阀体及内外缸体内的交变流场进行数值模拟,得到相应流道中的速度场、压力场和流线分布图。进一步地采用基于三维流场的可视化分析方法,清晰而全面地反映了各关键流道流体的流动状况。由此获得的减振器工作特性曲线与实际标准特性曲线相吻合,证实了模型的可行性和方法的有效性。所建立的分析模型和采用的仿真方法,为从机理上分析减振器能量耗散过程提供理论依据,同时,也为流道的结构优化设计提供快速、有效的手段。

Hydraulic damper is an important component of the travel unit of train,its damping characteristics are fulfilled by a group of damper valves of special structure.In order to optimize the whole runner structure of hydraulic damper cylinder and analyze the influence of local flow field on the damping characteristics when the key damper valve is in different open positions,it is necessary to use fluid dynamic 3D simulation calculation method to estimate its characteristics.Aiming at the structure and parameters of vertical damper used on a train of typical structure,a corresponding mathematical model and physical model are built.Alternating flow fields in valve body and in inner and outer cylinders under various typical vibration conditions are simulated by using CFX adaptive dynamic grid technology,then velocity fields,pressure fields and streamline distributions of corresponding runners are obtained.By further using visualized analysis method based on 3D flow field,the fluid flow condition of every key runner is reflected clearly and roundly.The obtained working curve of damper agrees with the practical standard characteristic curve,thus proving the feasibility of the analytical models and the effectiveness of the simulation method,which provides theory basis for analyzing the damper energy dissipation process from the mechanism,and also provides a quick and effective way for structure optimization design of runner.