轨道车辆车体半主动式磁流变吸振器的减振特性研究

A study on vibration reduction characteristics of semi-active magnetorheological vibration absorbers for vehicle bodies

以降低城市轨道交通车辆车体的垂向振动、提高乘客舒适度为目的,根据磁流变弹性体材料刚度可调、固有频率可变的特点,建立了包含磁流变弹性体的半主动吸振器的车轨垂向振动模型,提出了适用于城轨车辆的利用磁流变弹性体的动力吸振器设计方法。针对城市轨道车辆的客流量及车速变化频繁的特点,利用多元回归分析法拟合了半主动式磁流变吸振器的最佳设计频率表达式,研究刚度优化后的半主动式磁流变吸振器对车体垂向减振特性,并进一步指出了磁流变吸振器的优点。结果表明:在磁流变吸振器的有效工作频段内,半主动式磁流变吸振器在车体的各振动频率点的吸振能力都优于被动式吸振器,其宽频减振优势明显;经过最佳设计频率表达式修正的磁流变吸振器可与车体始终处于谐振状态,使车辆的运行品质时刻保持在优级。该项工作为利用磁流变弹性体的轨道车辆车体半主动式吸振器的应用提供了参考依据。

To reduce urban railway vehicle bodies’vertical vibration and improve passenger comfort based on the characteristics of magnetorheological elastic material,whose stiffness and natural frequency are adjustable,the vertical vibration model with semi-active vibration absorber including magnetorheological elastomer was established.The method of designing a dynamic vibration absorber using a magnetorheological elastomer,which is suitable for urban railway vehicles,was presented.Because urban railway vehicle traffic and speed change frequently,the best design frequency expression of the magnetorheological absorber can be obtained by multiple regression analysis.The vehicle body’s vertical vibration reduction characteristics with semi-active magnetorheological vibration absorber after-stiffness optimization was studied.Then the advantages of the magnetorheological vibration absorber were further established.The results show that the vibration absorptive capacity of the semi-active magnetorheological vibration absorber is superior to that of the passive vibration absorber at each of the vehicle body’s frequency points within the effective working frequency band of magnetorheological vibration absorbers.So the advantages of the broadband vibration damping are obvious.The magnetorheological absorber,which is modified by the best design frequency expression,can be in a resonant state with the vehicle body at all times to keep the vehicle consistently running at superior quality levels.The study provides a reference basis for the application of a semi-active vibration absorber utilizing a magnetorheological elastomer,which is used in urban railway vehicles.