Research on temperature of high-speed train axle box bearing considering lubrication state evolution and vehicle dynamics response

The temperature of axle box bearing is always one of the indicators used to monitor whether the high-speed train is running safely. In this paper, a thermal model of axle box bearing considering the change of bearing lubrication state and the operating condition of the high-speed train was established. Based on the analysis of the generation mechanism of frictional heat inside the bearing, the influence of proportion of grease involved in lubrication was introduced for the first time and a detailed temperature transfer system of the axle box system was established. At the same time, through the axle box bearing-vehicle system dynamics model, the vertical and lateral loads of the axle box bearing under different operating condition were obtained as input parameters of the axle box bearing thermal model, the temperature distribution curve of the bearing under different operating conditions was obtained. Finally, based on the long-term wireless transmission device system (WTDS) temperature monitoring data, the calculation results of the established model were verified. The verification results showed the reliability of the model established in this paper, and showed the necessity of considering the change of the internal lubrication state of the bearing when evaluating the axle box bearing temperature.