中文摘要：

应用多体动力学仿真软件NUCARS建立CRH2型动车组拖车的动力学模型,采用单变量谐波合成法模拟脉动风速场得到施加在动车组上的横风载荷,仿真得到风速分别为5,7.5,10,12.5,15,17.5,20,22.5,25和27.5m·s-1,以及车速分别为120,160,200,250,275,300,320和350 km·h-1时脱轨系数、轮重减载率和轮轴横向力等安全性指标的最大值;然后应用逐步回归方法,得到以风速和车速为自变量、以脱轨系数、轮重减载率和轮轴横向力最大值为因变量的二元二次多项式回归方程的最优回归模型,并在车速为380km·h-1、风速为30 m·s-1时外推验证了回归模型的正确性,以及在现有安全性指标限值下得到不同风速下的车速阈值.研究结果表明：当车速恒定时,CRH2型动车组的脱轨系数、轮轴横向力和轮重减载率的最大值与作用于动车组上的风速近似呈二次方关系;当风速恒定时,轮重减载率的最大值与车速也近似呈二次方关系,而脱轨系数和轮轴横向力的最大值与车速则近似呈线性关系.

英文摘要：

Using multi-body dynamics simulation software NUCARS,the dynamic model of the CRH2 EMU trailer was established.From the turbulent wind velocity field simulated by single variable harmonic synthesis method,the cross wind loads acting on the EMU were obtained.By simulation,the maximum values of such security indexes as the derailment coefficient,the wheel load reduction rate and the lateral axle force were got as the wind speeds were 5,7.5,10,12.5,15,17.5,20,22.5,25 and 27.5 m · s-1,and the train speeds were 120,160,200,250,275,300,320 and 350 km · h-1,respectively.Then by stepwise regression method,the optimal regression model of the binary quadratic polynomial regression equation was obtained,with the wind speed and train speed as the independent variables and the maximum values of the derailment coefficient,the wheel load reduction rate and the lateral axle force as the dependent variables.The correctness of regression model was verified through extrapolation at the train speed of 380 km· h-1 and the wind speed of 30 m · s-1,and the threshold of train speed under different wind speeds with the premise of the existing safety index limits was obtained.The results show that：when the train speed is constant,the relationship between the maximum values of the derailment coefficient,the wheel load reduction rate and the lateral axle force of the CRH2 EMU and the wind speed acting on the EMU is approximately quadratic,respectively.When the wind speed is constant,the relationship between the maximum wheel load reduction rate and the train speed is also approximately quadratic,whereas the relationship between the maximum values of the derailment coefficient and the lateral axle force and the train speed is approximately linear,respectively.