Simulation Analysis And Contrast Of Bogie Dynamic Performance In Highspeed Trainset

With the development of high-speed passenger vehicles and the understand and re-innovation of their technologies, the non-linear influences of high-speed bogie has been paid great attention by many specialists, i.e., for CRH5 bogie, the longitudinal stiffness in wheelset locating is more than 14MN/m, the axle length is 2.7m, which is 0.2m more than the usual axle length. In many non-linear influential factors of high-speed bogie, the primary locating mechanism needs to be traded off between the lateral stability and the curve negotiation performance, in order to further comprehend the concept of the rail-friendly design.CRH5 high-speed bogie is taken as the investigation subject in this paper. On the foundation of the understanding and mastering of ALSTOM's calculation methodology and results, the non-linear and linear models of CRH5 bogie were established. The non-linear model of high-speed bogie is included the typical non-linear links, for instance, the primary locating gear, the anti-roll rod mechanism and airspring suspension, etc., which is applied mainly to the analyses of non-linear critical velocity and curve negotiation. Meanwhile the linear model is based on the equivalent linearization of the above typical non-linear links, which is applied primarily to the motion modal analysis of full vehicle, etc.On contrast with ALSTOM's results, the linear and non-linear models of CRH5 high-speed bogie have the consistency in simulation calculations. The ALSTOM's bogie is modeled in VAMPIRE, which is equivalent to the above linear model. The both calculating data regularities are similar in the following analyses: full vehicle modal, critical velocity and curve negotiation, but the distance of which is existed because of the basic data allowance (for example, the wheel tread profile spline approximation) and non-linear link's influence (for example, the primary locating mechanism produced the disadvantage effects on the axle lateral force).By the non-linear simulation feature of ADAMS, the full vehicle and 4-vehicle trainset dynamical analyses can make the better understanding of the non-linear influences of high-speed bogie. According to the high-speed rail experiences from ALSTOM and other European companies, the viewpoint of conservative calculation should be adopted since the disadvantage influences from such as the wheelset back-back distance, the controlled gauge allowance and the wheel-rail wear, etc.. Generally, the critical velocity in the full-laden condition is defined as Max. velocity, and the one in 70% laden condition is defined as Max. commercial velocity. As the ALSTOM's conservative calculation method, which the gauge is shorten suitable in order to increase the equivalent conicity, it is shown in the critical velocitycontrast of the LM profile that both calculating results is consistent with each other, which all satisfy the requirement of 250km/h. Furthermore, the comparison of the four typical wheel treads (LM,LMA,XP55 and S1002) shows that profile XP55 has the better smooth in parameter variations, and profile LMA can be achieved the 300-350km/h requirement.In the curve negotiation contrast, the both regularities are conformed on the axle lateral force variations, but the distance of which is existed, and the Max error arrived at about 10KN. The more the longitudinal stiffness in wheelset locating is, the more the longitudinal creepage force in curve negotiation process. Correspondingly, the traction coefficients become increased, in result in the occurrence probability of the wheel slip enhanced. The wheel slip probability is dependant on the wheel tread profile, for instance, the traction coefficient for profile XP55 and LMA is relative lower. The wheel slip is one of the main reasons of flange contact. Since the orientation of high-speed bogie is deflexed in curve negotiation mostly by the wheel's longitudinal creepage forces, therefore, the higher results of the axle lateral forces is rational.