基于有限元功率流法的轮轨系统能量分布特性研究

为分析不平顺激励下轮轨系统内振动的分布及传递规律,采用轮轨动力学模型与有限元功率流相结合的方法,推导轮轨系统内各子系统输入功率流的计算公式,对比加速度与功率流两种指标在振动评价上的异同点,并分析能量在轮轨系统中的传递及分布规律。通过上述研究方法得到以下结论:功率流指标可直观给出振动过程中结构的输入能量及结构间能量的传递、消耗情况,加速度则反映结构的振动强度;列车运行时产生的低频能量(低于63Hz)主要输入到车辆子系统中,从而引起车辆子系统的低频响应;而高频能量(高于63Hz)主要传递至轨道系统,引起轨道结构的高频振动;轮对与转向架间的一系悬挂消耗了大量高频能量,而功率流流经二系悬挂后在全频率范围内均得到显著消耗,传递至车辆子系统的功率流由下至上在全频范围内发生衰减。

Study on Energy Distribution Characteristics of Wheel/Rail System Based on Finite Element Power Flow Method

In order to analyze the distribution and transmission law of vibration in the wheel-rail system under uneven excitation,the calculation formula of the input power flow of each subsystem in the wheel/rail system is derived,the similarities and differences between the two indexes of acceleration and power flow in the evaluation of vibration are compared,the transmission and distribution characteristics of energy in the wheel/rail system are analyzed by means of wheel/rail dynamic model and finite element power flow method.The research results show that:power flow indexes can be used to indicate the input energy and energy transfer and consumption in the process of vibration,and acceleration reflects the vibration intensity of the structure;during the train operation,the low frequency energy(less than 63 Hz)is mainly input to the vehicle subsystem,which causes the low frequency response;furthermore,the energy of high frequency(more than 63 Hz)is mainly transmitted to the rail system,which causes the high frequency vibration of track structure;the single stage suspension between the wheel and the bogie consumes a large amount of high frequency energy,the secondary suspension consumes the power flow in the whole frequency range when it flows from bogie to body,and the power flow transmitted to the vehicle subsystem is consumed in the whole frequency range from the bottom to the top.