制动条件下连挂救援动车组车钩垂向偏转行为

为了研究连挂救援动车组在制动条件下产生的冲击,建立了不同编组形式下的动车组动力学模型。考虑实际的车钩运动关系和缓冲器迟滞特性,建立了钩缓装置的动力学模型。制定了连挂救援动车组的运行安全阈值,分析了紧急制动时动车和钩缓系统的动力学响应,研究了直线工况下车钩的动态偏转行为与动车编组形式、制动减速度和车钩自由转角等参数对动车组运行安全性的影响。计算结果表明:A类动车组连挂救援B类动车组,直线上制动时连挂断面的压钩力和车钩点头角分别达到799.4 kN和11.5°,钩尾框托梁垂向力和车端垂向相对位移分别达到136.2 kN和126.2 mm,明显超过允许限值,即80 kN和95 mm,车钩力垂向分量会造成车体点头和轮重减载现象,从而导致局部结构破坏和车间运动干涉。当制动档位降到7级或车钩自由点头角低至4°时,钩尾框前箱托梁垂向力低于限值,而车端垂向相对位移超过限值; 当制动档位降到6级或车钩自由点头角低至2°时,可保证车端垂向相对位移低于允许值。

Vertical rotating behavior of coupler for multiple units to multiple units rescue under braking conditions

In order to study the braking-induced impact for multiple units(MU)to multiple units rescue, the different configuration types of MU dynamics models were built. Actual kinematic relations and hysteresis characteristics were considered in the established coupler/draft gear dynamics model. The threshold values of coupled rescue MU for running safety were formulated. The dynamics response of MU and coupler/draft gear system under emergency braking were analyzed. The dynamics rotational behavior of coupler on the straight line and the influences of MU configurations, braking decelerations and coupler free-rotation angles on MU running safety were studied. Computation result shows that in the rescue scene of MU A to MU B, the longitudinal compressed force of coupler and the vertical rotating angle of coupler reach 799.4 kN and 11.5°, respectively, and the subjected vertical force of front supporting beam and the vertical relative displacement between adjacent carbodies reach 136.2 kN and 126.2 mm, respectively, which exceed the limit values, 80 kN and 95 mm, respectively. The vertical force components lead to carbody pitch and wheel unloading, which results in the local structural damages and the MU motion interference. The subjected vertical force of front supporting beam is lower than the limit value when the braking level decreases to No.7 level or the free pitch angle of coupler decreases to 4°, but the vertical relative displacement between adjacent carbodies exceeds the limit value. The vertical relative displacement is lower than the limit value when the braking level decreases to No.6 level or the free pitch angle of coupler decreases to 2°. 2 tabs, 11 figs, 20 refs.