后轮对独立回转新型转向架曲线通过性能的研究

Study on Curve Negotiation Capability of the New Type Bogie with Independently Rotating Wheels in Rear Axle

后轮对独立回转新型无摇枕转向架的曲线导向性能主要取决于其前轴的一系纵向定位刚度,而后轴的一系纵向定位刚度对导向性影响较小。因此,为了同时保证其曲线导向性和直线稳定性,对转向架一系纵向刚度可采取前后轴非对称布置。建立具有14个自由度的非线性车辆模型和车辆通过曲线轨道时的运动方程,采用MATLAB语言编写计算程序,对4种非对称布置方案的转向架曲线导向性能进行仿真对比分析。仿真分析结果表明,当刚度以车辆中心对称布置时,若外侧轮对纵向刚度小,内侧轮对纵向刚度大,则前转向架性能基本保持不变,而后转向架曲线通过性能变差,但其摇头角比前后刚度较大的方案要好;当第一、第三轮对的纵向刚度较小和第二、第四轮对的刚度较大时,转向架曲线通过性能好,且又改善了其在直线上的横向稳定性,是较适合高速运行的转向架布置方案。

The oriented capability of the new type bogie with independently rotating wheels in rear axle is independent on the longitudinal rigidity in the primary suspension of the rear axle but dependent on longitudinal rigidity in the primary suspension of the front axle. Therefore, in order to meet the request of curve performance and improve the hunting stability effectively, the thought of asymmetrical longitudinal rigidity arrangement in the primary suspension is put forward. Dynamic mathematic nonlinear model for a vehicle with fourteen freedoms is established and equations of the motion are obtained to pass through the curve line. Associated program is made with MATLAB software too. The oriented capability of the four asymmetrical longitudinal rigidity arrangement schemes is analyzed and compared by using the designed program. It is showed that oriented capability of front bogie is changeless but oriented capability of rear bogie is bad, when longitudinal rigidity in the primary suspension is arranged symmetrically to vehicle center （yielding outboard axle and rigid inboard axle）, yet Yaw response is better than the scheme of the rigid with longitudinal rigidity in the primary suspension of front axle and rear axle. The scheme of the bogie with yielding front axle and rigid rear axle is adaptive to high speed running, which not only meets the request of curving performance but also improves the hunting stability effectively.