Hsiu-Ying Hwang* and Jia-Shiun Chen
The Journal of Mechanical Science and Technology, vol. 25, no. 10, pp.2519-2528, 2011

Abstract : This paper investigated a noise and vibration concern on a metro train while the train made turns. The study was conducted to identify the root causes of the vibration and noise through hardware experimental testing as well as dynamic computer simulation. The initial investigation indicated the noise came from the bogie of the train. It was between the slewing ring bearing and the friction sets. A lab test was established to duplicate the reported problem and to root out the causes. One-factor-at-a-time method was used to screen the main key factors. Under certain contact conditions, unsmooth turning would occur and cause the noise and vibration. Dynamic simulation was proposed in the study to predict the potential issue. A multibody dynamic model was built with train body, underbody, slewing ring bearing and friction set to simulate the train turning motion. The results showed unsmooth/discontinuous dynamic motions and torque oscillation behaviors. The stop-and-go and stick-and-slip motion led to the vibration. The analysis confirmed the unsmooth friction forces and adhesion could cause the noise and vibration. The computer simulation showed good correlation with the hardware testing. It demonstrated the computer dynamic simulation could be used to predict the potential friction induced vibration issues. In the study, a different substitute material was also investigated through the computer simulation. The results showed the vibration could be effectively reduced if ceramic compound friction material was used.

Keyword : Noise and vibration; Slewing ring bearing; Bogie noise and vibration; Dynamic simulation; Friction induced vibration; Design of experiments