Study on the Thermal Performance and Temperature Distribution of Ball Bearings in the Traction Motor of a High-Speed EMU

• Published in: Applied sciences 2020-06, Vol.10 (12), p.4373
• Main Authors: Wang, Yu, Cao, Junci, Tong, Qingbin, An, Guoping, Liu, Ruifang, Zhang, Yihuang, Yan, Hua
• Format: Article
• Language: English
• Subjects: ball bearing; Ball bearings; Comparative analysis; Contact angle; Convection; Cooling; Driving ability; Durability; Electric motors; Electric railroads; empirical formula; Fluid dynamics; Friction; Grease; Heat generation; Heat transfer; Heat transfer coefficients; High speed; Lubricants & lubrication; Materials; Mathematical models; Mechanical properties; Motors; Railcars; Railroads; Roller bearings; Temperature distribution; Thermal properties; traction motor; Trains; transient temperature distribution; Viscosity; Working conditions
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app10124373

The transient thermal performance of rolling bearings affects the mechanical performance and system safety of traction motors. Most of the traditional empirical formulas used in temperature analysis have been simplified and cannot be completely applied to the calculation of heat generation and convection heat transfer coefficients. Based on the comparative analysis of finite element transient temperature and experimental data, this paper proposes a correction method of mathematical model and derives an accurate calculation formula for the heat generation and lubricant convection heat transfer coefficient of ball bearings applicable for the non-driving end in the traction motor of a high-speed EMU (Electric Multiple Unit). The accuracy of the results has been verified by durability experiment data. In addition, with changes in speed, radial load and other factors taken into account, we have analyzed the influence of these time-varying factors on ball bearing temperature, as well as the temperature distribution law of each component in a grease-lubricated bearing, in a bid to lay a foundation for follow-up research on the heat transfer laws of traction motors and rolling bearings.