Development and stability analysis of a high‐speed train bearing system under variable speed conditions

Abstract

During a high‐speed train operation, the train speed changes frequently, resulting in motion change as a function of time. A dynamic model of a double‐row tapered roller bearing system of a high‐speed train under variable speed conditions is developed. The model takes into consideration the structural characteristics of one outer ring and two inner rings of the train bearing. The angle iteration method is used to determine the rotation angle of the roller within any time period, solving the difficult problem of determining the location of the roller. The outer ring and inner ring faults are captured by the model, and the model response is obtained under variable speed conditions. Experiments are carried out under two fault conditions to validate the model results. The simulation results are found to be in good agreement with the results of the formula, and the errors between the simulation results and the experimental results when the bearing has outer and inner ring faults are found to be, respectively, 5.97% and 2.59%, which demonstrates the effectiveness of the model. The influence of outer ring and inner ring faults on system stability is analyzed quantitatively using the Lempel–Ziv complexity. The results show that for low train acceleration, the inner ring fault has a more significant effect on the system stability, while for high acceleration, the outer ring fault has a more significant effect. However, when the train acceleration changes, the outer ring has a greater influence. In practice, train acceleration is usually small and does not frequently change in one operation cycle. Therefore, the inner ring fault of the bearing deserves more attention.

Vibration characteristics of defective axle box bearings in high-speed trains under track irregularity excitation

“…Based on these models, more reliable evidence for defect detection was provided. Liu et al [18][19][20] established a 12-DOF nonlinear dynamic model of high-speed train axle box bearing with outer ring faults, and compared and analyzed the nonlinear dynamic behavior of normal bearings and faulty bearings, based on this mechanical model, the temperature model [21] and lubrication model [22] were coupled with it, considering the influence of lubrication on system vibration and temperature characteristics, and explaining the mechanism of some fault phenomena that occur during the operation of high-speed trains. Gao et al [23] proposed a simplified dual-rotor system considering the nonlinear characteristics such as Hertz contact force and radial clearance of shaftbearings, the motion equation of an eight degree of freedom system is established, the motion equation of the eight-DOF system was established using the Lagrange equation, and comprehensive parameter analysis was conducted to gain a deeper understanding of the effects of defect depth and span, speed ratio, and imbalance between the two rotors on the nonlinear resonance response characteristics.…”

Dynamic analysis of axle box bearings on the high-speed train caused by wheel-rail excitation

“…The relationship between vibration impulses and localized defects with different edge shapes was analyzed. For a high-speed train running at variable speeds, Wang et al [18] and Liu et al [19] created a dynamic model of the axle box bearing and rotor system. They further analyzed the temperature and lubrication characteristics of the bearing using the original model and focused on the effects of bearing faults on system stability.…”