Dynamic Performance of C80 Railway Wagon Under the Influence of Wheel Polygons and Typical Mode Shapes of the Car Body

To investigate the influence of typical mode shapes and wheel polygons on the dynamic characteristics of railway freight car body, this study takes railway freight wagon C80 as the research object. Vehicle-level and system-level finite element models of the C80 railway wagon were developed, revealing that the lateral and vertical stiffness of railway freight cars significantly affects system mode. Furthermore, co-simulation using NASTRAN and SIMPACK was used to establish a fully flexible dynamic model of the C80 wagon. The influence of typical modal frequencies on the dynamic performance of the wagon was analyzed considering the wheel polygon and wear parameters. The results show that suppressing the torsional mode shape of the railway wagon reduces its impact on the derailment coefficient, wheel load reduction rate, axle transverse force and overturning coefficient by over 40 %. When the train speed corresponds to the polygon order, the wheel load reduction rate increases with the polygon wear depth under both the 10th order and 18th order conditions, by as much as 14.4 % when wear depth increases from 0.01 mm to the 0.05 mm for the 18th order condition. In addition, under the 6th order, 10th order, 16th order and 18th order polygon conditions, suppressing the torsional mode notably increased the wheel load reduction rate, especially under the 6th order polygon condition. This research provides valuable guidance for optimizing suspension parameters and controlling polygonal wear in railway wagons, offering a guiding basis for enhancing their dynamic performance of railway wagons.