A survey on the mechanism and countermeasures of low-frequency swaying of high-speed trains caused by aerodynamic loads

Abstract

The carbody abnormal vibration has significant impacts on the comfort and safety of high-speed train. Field measurements were conducted to study the low-frequency swaying of the carbody on a high-speed train operating on a railway line. According to the test results, the tail vehicle of the train swayed laterally in various places along the line. The lateral stability index of vehicle clearly exceeded the limit value when the carbody swayed. The predominant frequency of the lateral acceleration of the carbody was between 1.4 and 1.5 Hz. Through the simulation of computational fluid dynamics, it is confirmed that the yaw moment and lift force of the tail vehicle are greater than those of the middle and the head vehicles. Furthermore, the dynamics simulation show that aerodynamics disturbances may be the intensified cause of the abnormal swaying of the tail vehicle. Therefore, the study proposes the installation of inter-vehicle dampers. and optimizes the damping values of dampers based on GA-BP optimization algorithm, so as to weaken the abnormal swaying motion. The relevant simulation results offer a solution to address the abnormal swaying phenomenon in practical situations.