Equivalent Dynamic Model Of Vehicle-Passenger And Study On Its Dynamic Response

Railway passenger vehicle is moving towards higher speed and lower weight, which also triggers many problems. The excitation frequency of track will increase with the advance of running speed, and the structural stiffness and natural vibration frequency will reduce with lower weight. So the structure of vehicle is more likely to resonate in the high excitation frequency, which causes vehicle operation stability and ride comfort problems. These problems become more and more obvious and need to be solved after a few times large-scale speed up. The coupling vibration of passenger and vehicle body is hardly taken into account and the acceleration of a point on the floor of vehicle body is used to evaluate running stability and ride comfort in the usual dynamics analysis. In fact, it is more credible and in accord with the actual condition to consider the coupling vibration of passenger and vehicle body and evaluate running stability and ride comfort by the acceleration of human body. Because the flexible vibration of carbody is motivated, the train under high-speed circumstances is built to rigid-flexible coupling dynamic model. The high-speed train commonly employs power-distributed technology and the equipment, such as traction transformer, which is connected below carbody by elasticity suspension. The equipment is vibration source and weighs6t, which has an important influence on operation stability and ride comfort, so it is necessary to optimize suspension stiffness.At first, the paper summarizes the research about the construction of human body, and establishes vertical4DOFs (degrees of freedom) human model with high goodness-of-fit and6DOFs human model considering human body and seat for3DOFs separately. After that, four dynamic models are built by making use of ANSYS and SIMPACK based on certain bullet train. The calculation of vibration response and operation stability of four models shows that it is extremely important to consider vehicle body as elastic body and add suspension equipment. At last, the two established human models are introduced to the rigid-flexible coupling dynamic model with elastic vehicle and suspension equipment, and vibration response, operation stability and ride comfort of this model are analyzed. The variation of various performance indexes is analyzed after the joint of human body, and the ride comfort is considered by the acceleration on the human body. In the meantime, the suspension stiffness of the greatest weight equipments is optimized to achieve preferable ride comfort.