The Simulation Of Train's Air Brake System With 104 Distribution Valve

Railway is the one of most important transportations of our country, in the development of our country's economy, it takes the important role of the freight and passenger transportation. To complete this difficulty task, the train's pull weight and run speed always to rise, therefore, brake technology is being important in railway development. Since 1997, the ministry of railway has raised the run speed for six times in the main lines. The raising of train speed, is the most strict challenge for the brake technology.As railway develops to high speed and heavy haul, the research on braking system is very important. Brake problem is an ancient problem along with railway, its studies always use the traditional method of experiment, on the one hand, it is because of air brake system's structure simple , is easy to test; on the other hand, it is because of the limitation of air flow dynamics in early stage, is hard to combine with air brake system. Because of the railway need develops to high speed and heavy haul for the present, and air braking system became more complex, only depend on using the method of experiment means more difficulty, more time and money consuming, especially due to the discrete of brake capability in experiment, make people begin to change research direction to simulation. The raising of computer operational ability, make the condition to work out mathematics model, and promote the brake system quickly development of simulated research.In this paper, through the study and analyze serious about train brake system with 104 distribution valve and according to air flow theory and the principle of 104 distribution valve, the physical model of this valve is established, and the simulation software for train braking system, which is applicable to predict the performance of the braking system and analyze the parameter effect, is developed. Calculated a series simulation results, such as performance, emergency and release speeds, and pressure curves, compared with experiment data, verify the correctness of the program.The program adopts numerical method, and as the core of calculate the air flow in brake system, to get every time the physical state of all pipeline and big cylinder of braking system, and then get the property of brake system for simulation. It is not only getting the gas state of brake system at every time, but also clearly known every piston's location and track in any time during brake action. At the same time, the program can be used to predict the performance of the brake system, and can analyze each parameter's influence for brake system, therefore, it is a good tool for analyzing brake mechanism and optimizing brake system, can offer reference data for other research work (as the research of train longitudinal dynamics).