外部激励下齿轮箱振动分析与动应力评估

Vibration Analysis and Dynamic Stress Evaluation of Gearbox UnderExternal Excitation

针对高速动车齿轮箱箱体应力集中问题,从轨道不平顺激励的角度对其箱体的振动特性与动应力分布进行评估。首先建立了高速动车的齿轮箱、转向架及整车的刚柔耦合动力学模型,其次利用转向架滚振实验台测量了动车齿轮箱在轨道不平顺激励下的振动加速度,其中工况选取了100km/h、200km/h及300km/h匀速运行工况。依据实验结果对动车系统的铰接类型、力元类型与参数进行了匹配性调整。最后仿真计算了齿轮箱箱体仅在轨道不平顺激励下的动应力,发现箱体整体等效应力主要集中于小齿轮端箱体处、小齿轮与大齿轮端箱体过渡联接处,其中在100km/h、200km/h和300km/h工况下,箱体平均等效应力范围依次为(2.03~2.30)MPa、(3.87~4.29)MPa、(6.81~7.25)MPa。发现轨道不平顺激励对箱体的振动特性产生一定影响,且箱体易出现应力集中现象。

Aiming at the problem of stress concentration in the gearbox case of high-speed EMU,the vibration characteristics and dynamic stress distribution of the case were evaluated from the perspective of trach irregularity excitation.Firstly,the rigidflexible coupling dynamic model of the gearbox,bogie and the whole vehicle of the high-speed EMU is established.Secondly,the vibration acceleration of the gearbox of the EMU under the excitation of track irregularity is measured by using the bogie rolling vibration test bench,and the working condition is selected 100km/h,200km/h and 300km/h uniform speed operation conditions.According to the experimental results,the articulation type force element type and parameters of the EMU system were adjusted to match.Finally,the simulation calculated the dynamic stress of the gearbox case only under the excitation of track irregularities.lt was found that the overall equivalent stress of the case was mainly concentrated at the small gear end case and the transition joint between the small gear and the large gear end case.Under 100km/h,200km/h and 300km/h conditions,the average equivalent stress range of the box is(2.03~2.30)MPa,(3.87~4.29)MPa,(6.81~7.25)MPa lt is found that the excitation of track irregularities has a certain impact on the vibration characteristics of the box,and the box is prone to stress concentration.