基于Newmark-β预测校正积分法的高速车辆垂向—纵向耦合振动研究

Study on the Longitudinal-Vertical Coupling Vibration of High-Speed Vehicle Based on Newmark-β Forecast-Correction Integral Method

为有效评估轮对动平衡对车辆垂向和纵向振动系统的影响,以CRH_2型动车组为研究对象,建立具有13个自由度的车辆垂向—纵向耦合振动数学模型,基于Newmark-β预测校正积分法,应用Matlab软件求解系统的振动响应,计算结果与传统多体动力学软件UM的相一致,验证了数学模型和求解算法的准确可靠。在此基础上,分析轮对动平衡对车辆垂向和纵向振动响应的影响,提出优化措施。结果表明:速度为60和300km·h^(-1)时轮对动平衡引起的激扰力频率与车辆自振频率接近,对应的振动频率为6和31 Hz,车辆运行平稳性降低;采用非线性纵向刚度牵引拉杆,可以有效降低由轮对动平衡引起的6和31 Hz左右的车辆振动,提高乘坐舒适性。

Taking the CRH2 EMU as the research object,a mathematical model with 13 degrees of freedom for the longitudinal-vertical coupling vibration of vehicle was established to effectively evaluate the influence of wheelset dynamic balance on the vertical and longitudinal vibration system of vehicle.Based on Newmark-βforecast-correction integral method,the vibration response of the system was solved by Matlab software.The calculation results agreed well with those obtained by traditional multi-body dynamic software UM.The accuracy and reliability of the mathematical model and the algorithm were verified.On this basis,the effects of wheelset dynamic balance on the vertical and longitudinal vibration responses of vehicle were analyzed,and the optimization measures were proposed.Results show that,when the speed is 60 and 300 km·h-1,the frequency of excitation force caused by the dynamic balance of wheelset is close to the natural frequency of vehicle.The corresponding vibration frequency is 6 and 31 Hz,and the vehicle running stability decreases.The use of nonlinear longitudinal stiffness traction rod can effectively reduce vehicle vibration around 6 and 31 Hz caused by the dynamic balance of wheelset,and improve ride comfort.