Design And Performance Analysis Of Railway Hump Vehicle Deceleration System

For the past few years,with the development of heavy-load railway transportation technology,it is demanded urgently for the hump reducer to complete the speed regulation of large-axle heavy vehicles.Therefore,a new deceleration system is proposed in this paper.Taking the deceleration system as the research object,the performance of the decelerating system is simulated and analyzed by using Pro/E,ANSYS,Adams and AMESim software.The main contents are as follows:For the demand of speed control of freight cars with heavy wheel load in hump yard,the hump reducer structure is redesigned.The brake force parameters of the new hump reducer are calculated,and the three-dimensional model of the new reducer is established.Based on the kinematic analysis of the reducer,the displacement,velocity and acceleration curves of each component of the reducer are obtained.On the basis of the kinematic analysis,the force balance equation of each component is derived by using the principle of D’Alembert,and the constraint reaction force of each motion pair is calculated by MATLAB programming.With the application of the software ADAMS,the dynamics simulation model of hump speed reducer is built.By using the software ANSYS,braking track is made.flexible,and the rigid body brake rail in ADAMS model is replaced by the flexible braking track.The rigid and flexible coupling dynamic model of hump reducer is established.The influence of elastic deformation of brake rail on the positive pressure of brake rail and wheel in the braking process of reducer is simulated and analyzed.The change rule of positive pressure of brake rail and wheel in the braking process is obtained.Furthermore,the proper distance between the two brake rails is determined when the reducer is braked,and the hydraulic cylinder pressure of four brake grades are determined.The hydraulic system of hump reducer is designed.The hydraulic system model is established in AMESim.ADAMS is combined with AMESim.The joint between the two software simulation interfaces is set up to accomplish the interaction and establish the mechanical-hydraulic joint simulation model of the hump reducer.The joint simulation model is used to simulate the braking of 27t axle load truck.The dynamic characteristics of hydraulic system and the rule of reducer braking force change are analyzed.The results show that the new deceleration system has a good braking effect on 27t axle heavy truck.