驼峰车辆减速器制动噪声的复特征值分析

为研究驼峰车辆减速器对下溜车列进行制动时发出的高频制动噪声问题，以驼峰车辆减速器为研究对象，在ABAQUS软件中建立制动系统有限元分析模型。通过采用复特征值分析理论对制动系统的稳定性进行分析，获得了振动系统不稳定模态在频域上的分布。现场采集制动尖叫噪声并分析其主要振动频率，与理论预测结果进行对比得到相对误差。结合振动频率的分岔曲线和振动模态的耦合情况，对影响制动系统产生不稳定模态的因素进行分析。结果表明，制动轨与车轮接触面间的摩擦系数在0.07~0.17区间内增大时，制动系统发生尖叫噪声的趋势增大，同时，制动轨作用在车轮上的侧向力在50~260 kN区间内增大时，对制动系统也有同样的影响。而被制动车辆的初速度对于制动系统发生尖叫噪声的倾向影响并不明显。可见，摩擦系数和制动轨作用力的变化对车辆减速器在制动过程中产生高频制动噪声的倾向具有重要影响。

A Complex Eigenvalue Analysis of Braking Noise of a Hump Car Retarder

In order to study the high-frequency noise generated by the hump car retarder when braking the rolling train, taking the hump car retarder as the research object, the finite element analysis model of the braking system was established in ABAQUS software. The complex eigenvalue analysis theory was used to investigate the stability of the braking system, and the distribution of the unstable modes of the vibration system in the frequency domain was obtained. The braking squeal noise was collected on site and its main vibration frequency was analyzed. The relative error was obtained by comparing with the theoretical prediction results. Combined with the bifurcation curve of the vibration frequency and the coupling of the vibration modes, the factors affecting the unstable modes of the braking system were analyzed. The results show that when the friction coefficient of the contact surface between the brake rail and the wheel increases in the range of 0.07 ~ 0.17, the tendency of squeal noise in the braking system increases. At the same time, when the lateral force exerted by the brake rail on the wheel increases in the range of 50 ~ 260 kN, it also has the same impact on the brake system. The initial speed of the braked vehicle has no obvious effect on the tendency of squeal noise. It is concluded that the changes of friction coefficient and braking rail force have an important impact on the tendency of vehicle reducer to produce high-frequency braking noise during braking.