轮轨系统车轮的高频振动特性

High-frequency vibration characteristics of wheels in wheel-rail system

建立了车辆-轨道-路基耦合系统振动分析模型,考虑轨道不平顺激励及轮轨接触区滤波,模拟了轮轨间随机振动垂向作用力。建立了车轮三维实体有限元模型,考虑了名义接触点、轮缘和车轮外侧3个轮轨接触位置,模拟了车轮系统在随机振动垂向荷载作用下的高频振动特性。分析结果表明:当列车以200km.h-1行驶在有砟轨道上时,轮缘的振动加速度响应最大,达到870m.s-2,辐板次之,可达493m.s-2,轮毂振动响应最小,为457m.s-2。在名义接触点进行激励时,辐板振动响应最大,可达563m.s-2,在轮缘接触点对车轮进行激励时,辐板振动响应为492m.s-2,在车轮外侧进行激励时,辐板振动响应最小,为301m.s-2。车轮各部位的主要振动峰值都集中在1 000～3 000Hz范围内,其中振动最大加速度集中在1 400Hz左右,在更高的频域范围中,由于波数过滤器作用很强,振动响应并不突出。

A coupling vibration model of vehicle-track-subgrade system was established, track irregularities and the contact filters in wheel-rail contact areas were considered, and wheel-rail vertical random forces were simulated. A 3D entity finite element model of wheel system was established, three contact positions were considered, including the nominal contact point, rim and lateral of wheel, and the vibration characters of wheel system in high-frequency domains due to vertical random forces were analyzed. Analysis result shows that the vibration acceleration responses of wheel rim, radial plate and wheel hub are 870, 493 and 457 m·s^-2respectively when train runs on ballast track at 200 km· h^- 1, the response of rim is highest, and the response of wheel hub is lowest. When the nominal contact point, rim point and outer of wheel were excited respectively, the vibration acceleration responses of radial plate are 563, 492 and 301 m·s^-2 respectively, the vibration response of radial plate due to the excitation on the nominal contact point of wheel is highest. The high-amplitude vibration spectrum of each part of wheel distributes in 1 000-3 000 Hz, and the frequencies of the maximum vibration acceleration on wheel are about 1 400 Hz, the vibration responses in higher-frequency domains are not prominent due to the strong role of wave number filter. 14 figs, 12 refs.