基于涡激振动的动车组隧道内列尾横向晃动机理

针对时速160 km动车组在单线隧道内列尾横向晃动问题，提出列尾气流涡脱效应引起车体涡激振动而导致列尾横向晃动的机理，研究了车辆悬挂参数改进等相关抑制措施；根据某动力车结构参数，建立车辆横向动力学模型，结合半经验非线性涡激振子模型，实现涡激振动时车辆流固耦合横向动力学计算。计算结果表明：单线隧道内动车组列尾较大的横向涡激力以及涡激频率与车体蛇行频率共振是引起晃车的主要原因；减小横向涡激力、提高车辆蛇行运动稳定性是减小晃车幅值的有效措施；针对该动力车，需避免较低等效锥度的轮轨接触，以防车辆一次蛇行导致涡激振动加剧；当转向架抗蛇行减振器阻尼由800 kN·s·m^-1减小到400 kN·s·m^-1，涡激共振时车体后端横向振动加速度幅值减小40%；车辆二系横向悬挂采用天棚阻尼半主动控制时，可以有效减小涡激共振区车体横向振动幅值，并能兼顾车体前后端横向平稳性。

Mechanism of train tail lateral sway of EMUs in tunnel based on vortex-induced vibration

Aiming at the train tail lateral sway of 160 km·h-1 electric multiple units (EMUs), which occurs in single-track tunnels, the mechanism was put forward that the vortex shedding effect of gas flow in the train tail causes the vortex-induced vibration of the car-body and results in the lateral sway of the train tail. Relevant mitigation measures, such as the optimization of vehicle suspension parameters, were studied. Based on the structural parameters of a certain type of locomotive, the vehicle lateral dynamics model was established and combined with the semi-empirical nonlinear vortex-induced vibrator model to enable the fluid-solid coupling lateral dynamics calculation during the vortex-induced vibration. Calculation results show that a large lateral vortex-induced force acting on the train tail of EMUs in a single-track tunnel and the resonance between the vortex-induced frequency and the car-body hunting frequency are the main causes of car-body sway. Reducing the lateral vortex-induced force and improving the vehicle hunting stability are effective measures to reduce the amplitude of the car-body sway. For this type of locomotive, avoiding wheel-rail contact with a lower equivalent conicity is required to prevent aggravation of the vortex-induced vibration by vehicle primary hunting behavior. When the damping of the yaw damper is reduced from 800 kN·s·m-1 to 400 kN·s·m-1, the lateral vibration acceleration amplitude in the rear end of the car-body during vortex-induced resonance is reduced by 40%. When the semi-active control with skyhook damping in the secondary lateral suspension is adopted, the lateral vibration amplitude of the car-body in the vortex-induced resonance zone is effectively reduced. Moreover, the lateral ride comfort at the front and rear ends of the car-body can be guaranteed. 1 tab, 9 figs, 29 refs.