| With the rapid development of China’s high-speed railway technology,the speed of high-speed trains is getting higher and higher.China’s high-speed railway has repeatedly broken the world’s highest operating speed record and China has become the country with the highest operating speed of high-speed rail in the world.With the increase of operating speed of high-speed train,the safety of train operation has gradually become more complicated.Crosswinds in nature can worsen the aerodynamics of high-speed train on embankments,directly threatening the safety of train operation.Therefore,it is necessary to carry out a systematic study on the aerodynamic performance and operating safety of high-speed train on embankments under cross winds.This article takes the ICE high-speed EMU as the research object.Firstly,FLUENT software is used to analyze the aerodynamics of the high-speed train on embankment to obtain the aerodynamic load of the high-speed train under crosswinds.Secondly,the multi-body dynamics model of the high-speed train is built by the multi-body dynamics software SIMPACK and the aerodynamic load of the high-speed train under crosswind is applied to the model in order to simulate the running of high speed train and calculate the various safety indexes of the train.Finally,based on the basic theory of reliability,the reliability of the high-speed train embankment under crosswinds is evaluated.The main research contents are as follows:(1)A three-dimensional model of a high-speed train with three carriage on an embankment is established by ANSYS-ICEM,and the fluid simulation software FLUENT is used to simulate the flow field when a high-speed train runs on an embankment under crosswinds considering different embankment heights and wind deflection angles.Analyze the distribution of pressure field and velocity field on the train surface and surrounding flow field,and the changes of train aerodynamic coefficient with embankment height and wind deflection angle.(2)Based on the multi-body dynamics theory,a multi-body dynamics model of a high-speed train is established by the software SIMPACK,and the aerodynamic load on the cars subjected to crosswinds is applied to the train in a time-stimulated manner.The vehicle’s rate of the wheel,overturning coefficient,and other safety assessment indicators,and then comparative analysis of the safety indicators under various working condition.(3)Considering the impact of wind speed pulsation on running safety of train,the pulsating wind speed is simulated based on Cooper theory and harmonic superposition method,and the pulsating wind speed is converted into pulsating force which is applied to the train multi-body dynamics model.Based on the reliability theory,the performance function of the train under the action of random wind is calculated by the response surface method,and then the corresponding failure probability of the train is solved,and the operation safety of the train is evaluated. |
