声子晶体理论的钢轨吸振器设计及评估方法

Design and Evaluation Methods of Rail Vibration Absorbers Based on Phononic Crystal Theory

针对地铁小半径曲线P2共振型波磨,使用声子晶体带隙理论的钢轨吸振器设计方法,将吸振器简化为弹簧-阻尼-质量模型,并引入到车辆-轨道耦合动力学时域分析模型中,建立车辆通过波磨段时吸振器有效减振频段及效果的评估方法。结果表明:声子晶体局域共振机理设计的吸振器,可满足车辆通过P2共振型波磨时的减振需求,且不突破吸振器安装空间限值;时域评估方法预测的吸振器有效减振频段略宽且完全涵盖声子晶体理论的带隙;与传统吸振器设计方法相比,声子晶体理论设计的吸振器的减振效果更好;吸振器有效减振频段相对较窄,一种设计很难有效应对现场不同路段P2共振频率波动导致的波磨损伤差异,这或许就是工程中吸振器效果不稳定的原因所在。

Regarding the P2 resonant corrugation on the sharp curved metro line,the design method of rail vibration absorbers based on phononic crystal band gap theory was proposed.The vibration absorber was simplified as a spring‒damping‒mass model,which was introduced into the time‒domain analysis model of vehicle‒track coupling dynamics.The evaluation method for determining the frequency band of effective vibration reduction and the effect of vibration absorbers,when vehicle passed through the wave corrugation section,was established.The results show that the vibration absorber designed by the local resonance mechanism of phononic crystals can meet the vibration reduction requirements when vehicle passes through P2 resonant corrugation without breaking through the installation space limit of the vibration absorber.The frequency band for effective vibration reduction of the vibration absorber predicted by time-domain evaluation method is slightly wider and completely covers the band gap of phononic crystal theory.Compared with the traditional vibration absorbers,the vibration absorber designed by phononic crystal theory has better vibration reduction effect.Considering that the effective frequency band of vibration absorber is relatively narrow,it is difficult for a single design to effectively deal with the difference of wave abrasion caused by P2 resonance frequency fluctuation in different sections,which may be the reason for the unstable effect of vibration absorbers in engineering.