为了研究重载列车在惰行和制动工况下通过曲线时的轮轨接触特性,采用数值方法建立单自由度车辆和全自由度车辆混合的列车动力学模型,对比分析了惰行和制动工况下列车曲线通过时的运行安全性、车轮磨耗分布特征、轮轨滚动阻力特性影响。结果表明:考虑车钩负载效应和闸瓦贴靠车轮作用的列车模型在曲线制动工况下的轮轨横向力和脱轨系数指标均比惰行工况时略差,但轮重减载率指标几乎相当;由于制动时闸瓦压力增大了轮对的摇头约束,导致通过曲线时导向车轮磨耗功率的动态分布区域比惰行时更靠近轮缘处;制动工况下的牵引比率随曲线曲度线性变化的范围比惰行工况时大,且随着制动强度的增大,牵引比率也逐渐增大。
In order to study the characteristics of wheel-rail contact of heavy haul train negotiating curve route under idling and braking conditions, train dynamic models mixed with single DOF and full DOF were built using numerical method. Running safety, wheel wear distribution and wheel-rail rolling resistance characteristics of heavy haul train during curve negotiating under idling and braking conditions were analyzed contrastively. The results indicated that the lateral wheel-rail force and derailment factor in train model passing through a curve with coupler load effects and the effects of brake shoe pressing on wheels under braking condition were larger than those under idling condition, while the wheel unloading rate remained basically the same under the two running conditions. The yawing constraint of the wheelset was enhanced with the pressure of brake shoes during braking, causing the dynamic distribution area of guide wheel wear power to be closer to the flange, compared with the idle running condition. The scope of traction ratio linearly changing with the degree of curve under braking condition was larger than that under idling condition. The traction ratio was gradually increasing with the increase of the braking strength.