Modeling And Simulation Research On Freight Train Braking System

With the rapid development of the country economy, and the sharp increase of railway transport volume, the conflict between traffic volume and transportation capacity is becoming more and more outstanding. The heavy-haul transportation has been a main developing direction in Chinese railway transportation. Due to the development of heavy-haul transportation, the performance for break system in heavy haul train has been put forward with a higher requirement. Therefore, conducting a study on the brake system for freight car is particularly urgent.Experiment is always an indispensable means for researching the brake problem, but it will occupy the operation lines, which not only wastes time and costs plenty of funds, but also results comparatively dispersion of the data, bringing lots of inconvenience to the research and development of new products. The development of the computer technology creates conditions for establishing the simulation model about brake system and promotes the simulation research of brake system greatly. It will save plenty of human power, material and financial resource in establishing the simulation model, data analysis and calculation with the method of computer,which will simulate kinds of complicated working conditions, reduce product research cost and shorten the period of development. Nowadays, researchers, home and aboard, mainly adopt two methods in the area of numerical simulation for brake system performance, the one is programming program, and the other is making the secondary development with common simulation software. AMESim is a graphical modeling platform based on physics model, the advantage of its high accuracy and reliability has been proved by the successful use in the aviation and automotive field.120 air control valve is the most key component in the 120 type brake device, which is the main one for the freight train braking system in our country at present, and it affects the brake system performance directly. According to the working principle of 120 air control valve and the airflow theory, the paper builds the simulation model about braking system for single freight car with 120 air control valve on the platform of AMESim, and makes the comparative research with the experiment data.The correctness and reliability for the simulation model have been proved. In this process, the moving components in brake system are studied, and the effects of valve parameters to braking system performance are analyzed. Finally, the simulation model of braking system in freight train is built, which can realize the 120 valve's variety work functions. Subsequently, the train formation about 120 is simulated. The study has guiding significance for optimizing the air brake valve and braking system, and lays the groundwork for further simulation of the braking system faults and the diagnosis analysis.