等值同向轮径差对地铁车辆曲线通过能力的影响

Influence of equivalent in-phase wheel diameter difference on the curve passing capacity of subway vehicles

针对地铁车轮在运行过程中出现等值同向轮径差的问题,建立车辆系统动力学模型,计算分析等值同向轮径差对地铁车辆曲线通过能力的影响。结果表明:当同一车厢前、后转向架同时存在等值同向轮径差时,外侧车轮通过曲线线路的动力学响应更强烈。当外侧车轮直径大于内侧车轮直径时,有利于地铁车辆通过小半径曲线;反之,会加剧轮轨之间的作用力,增加地铁车辆脱轨的风险。当曲线半径为300 m、轮径差为1.0 mm时,外侧车轮的脱轨系数超过安全限值,轮重减载率接近安全限值,因此将脱轨系数和轮重减载率作为判断该工况安全限值的指标;同时,为保证车辆安全运行,半径为300 m的曲线线路的运行速度应控制在65 km/h以下或将0.5 mm作为车轮镟修指标。

Aiming at the problem of subway equivalent in-phase wheel diameter difference during the operation of subway wheels,the vehicle system dynamics model was established to calculate and analyze the influence of the equivalent in-phase wheel diameter difference on the curve passing capacity of subway vehicles.The results show that when there is an equivalent in-phase wheel diameter difference between the front and rear bogies of the same carriage,the dynamic response of the outer wheels through the curved line is stronger.When the outer wheel diameter is larger than the inner wheel diameter,it is beneficial for the subway vehicle to pass through the small radius curve,on the contrary,it increases the force between the wheel/rail and the risk of derailment of the subway vehicle.When the curve radius is 300 m and the wheel diameter difference is 1.0 mm,the derailment coefficient and wheel unloading rate of the outer wheel exceedes the safety limit.Therefore,the derailment coefficient and wheel load reduction rate are used as the safety limit for judging the working condition.At the same time,in order to ensure the safe operation of the vehicle,the operating speed should be controlled below 65 km/h,or 0.5 mm should be used as the index for wheel repair on the 300 m curve.