Safety adaptability test and calculation of tail push-type operation of power car

The safety adaptability of power concentrated EMUs under the tail push-type operation of power car was systematically explored with a combination of test and simulation calculation. A dynamics performance test was conducted for the tail push-type operation of power car to analyze its safety adaptability on conditions such as the straight line, and curve of 300 m radius. A 12-settings system dynamics model was constructed by multi-body dynamics and substructure methods, including a tail power car, two adjacent trailers, and a 3D dynamics model of tight-lock coupler. The dynamics model was fully revised and validated by the test data. The simulations for more dangerous cases were carried out to analyze the safety of such a power car tail push-type operation. The safety adaptability of this operation on different lines was discussed. Research results show that under the curve condition of 300 m radius, the simulation calculation is basically consistent with experimental results. The pushing force of coupler has a small impact on the safety of tail power car operation. Due to the longitudinal creep of the wheel rail, the safety index of tail power car operation decreases under larger pushing force, while the one of adjacent trailers is relatively significantly affected by the pushing force. During the lateral pushing of tail power roof through the No.12 and No.9 turnout, the safety indicators of power car and its adjacent trailer increase with the rise of the pushing force of coupler. When the power car plays the pushing force of 100% and passes through the No.9 turnout laterally, the wheel load reduction rate and the lateral force of the wheel axle will exceed the limit. Therefore, the coupler pushing force of the power car passing through the turnout laterally should be minimized as much as possible.