Abstract:

The piecewise linear model of friction draft gear is modified by the additional sticking friction force and the additional damping force based on vehicle impact data; train air brake characteristic multi-parameter mathematic method is used to study heavy haul train brake characteristic; on the basis of draft gear dynamic modification model and air brake multi-parameter mathematic method, the heavy haul train longitudinal impulse dynamics of different line conditions and brake operation is analyzed . The results show that the draft gear piecewise linear dynamic modification model can actually reflect the hysteresis characteristic of draft gear, nonlinear peak and smooth transition between loading curve and unloading curve; the results of air brake multi-parameter mathematic method agrees well with the test in the emergency and service braking operation; longitudinal train dynamic model can simulate Daqin heavy haul train longitudinal impulse problems, which agrees well with the test of train running.

Key words: air brake, draft gear dynamics, longitudinal impulse, heavy haul train