Study On System Dynamics Of Heavy Haul Train

Heavy haul transportation is another mark of railway modern except for the high speed train. Since the 1960s, many countries have paid more attention to the development of heavy haul transportation. For a long time, the railway transport has taken an important part in our country because of its remarkable advantages, such as high speed, huge capacity, safety, convenience and low energy consumption. But inconsistency between rail transportation capacity and needs is quite serious. The development of heavy haul transportation is an important way and basic measure to solve the increasingly inconsistency of rail freight transportation. It can greatly improve our rail transportation capacity. However, with the increasing of train formation and hauling weight, problems of safety in transportation have become prominent. The traction force and braking force will increase with the increase of weight and length of freight train, so the propagation time of brake wave is long, therefore, so much problems sticking out which have a negative effect on the healthy development of heavy haul transportation. Moreover, the force state of heavy haul train is more complex than that of normal train because of the complexity of profile and large length of train. There are so many accidents in the operation of train which have become a prominent problem, such as longitudinal impulse, braking failure, coupler failure, derailment and the destructive effect on railway line.The system dynamics of heavy haul train is found with the development of heavy haul train in the world. The research object of this is the dynamic behavior of train running on the railway line, and it is expected to make an analysis on the reaction and rrelationship between rolling stocks and line, moreover, it is hoped to improve the dynamic relationship by means of some reasonable measures and reduce the harmful effect, all this measures are expected to guarantee the safety and reliability of heavy haul train. The dynamics of heavy haul train has lots of parts and it is related to so many areas, such as locomotive, rolling stock, line, and some other aspects, like formation and operation of train.The wagon as the basic part of train is the research object of this paper, and the effect of structure and characteristic parameters on dynamics were analyzed firstly. Then, according to the limitation of traditional researchs on dynamics of train, a method named Modular Modeling Method Based on Circular-Variable has been used in this thesis to make a system study on dynamics of heavy haul train. The detailed aspects are as follows:(1) Interaction and relationship between heavy haul train and railway line, including straight line, curve, ramp and the space curve made up by the above three types of line;(2) The change trend of dynamics of train along with the change of formation, including the amount of locomotive and rolling stocks, the position of locomotive and mixed formation of light and heavy cars, and so on; (3) The close relationship between the operation of locomotive and system dynamics, it is aimed to make a analyze on the relationship among acceleration, constant speed (including ideal and equilibrium constant speed) and deceleration;(4) A preliminary simulation of the air brake system of heavy haul train, the propagation characteristic of air wave in brake system of train and the effect of parameters on brake characteristic.We can conclude from the detailed analysis that the structure parameters and characteristic parameters have an important effect on the dynamics of heavy haul wagon. Though the comprehensive analysis of dynamics of heavy haul train, it is easy for us to know the relationship between train dynamics and railway line, formation and operation of train. Furthermore, the analysis results show the dynamic behavior of heavy haul train.