Simulation Analysis On The Brake Performance Of Heavy Vehicle Hydraulic Retarder

With the request of people to the vehicle safety and the comfort, it is much more important to enhance the vehicle brake performance. Especially the city buses, the heavy vehicles and the coaches, which drive in the mountain area, must be equipped with auxiliary braking system, because the auxiliary braking system can obviously reduce the load of the service brake. Hydraulic retarder has many advantages such as: high braking power, high brake stabilization and durable performance . So the applications of the Hydraulic retarder are more and more wide. Sum up, it is necessary to research the relationship between Hydraulic retarder and the vehicle brake system.According to the project of vehicle intelligent hydraulic retarder key technology research, do the following :(1)The dissertation summarizes the brake system of vehicle and introduces the working principle and characteristics of hydraulic retarder.(2)The analysis of vehicle Braking process, are the foundation for simulation model.(3)Make performance experiments of hydraulic retarder; and analyze experimental data to calculate the parameters of the retarder, such as:λM,λA,ξcj,ξmc.(4)Using MATLAB, this paper processes the dynamic simulation of the vehicle brake process and hydraulic retarder combine brake. Based on the vehicle brake experiment, the analysis of simulation results and the results of brake performance experiment, this paper forecasts the brake performance of vehicles which equip the hydraulic retarder and analyzes the effects the hydraulic retarder to the brake performance. Using Matlab/Stateflow, control logic of constant speed is established.The research shows: in emergency braking simulation, hydraulic retarder can reduce 20% of brake time and brake distance. The hydraulic retarder also can replace the service brake system sometimes. Base on the compare of vehicle brake experiment and simulation, proved the simulation model is true.The researches of this paper afford theory gist, technology reference and viable research method for the exploitation and application of hydraulic retarder.