Research About The Working Proces Numerical Simulation And Performance Optimization Of Engine Bleeding Brake

With the improvement of traffic and automobile large-scale，the speed and loadcapacity of vehicle have a great improvement. Modern automobile has higher andhigher demands for automobile braking performance.It has become a trend and evenperemptory rule for adding engine supplementary brake device in the moderncommercial vehicles, especially in large commercial vehicles. As a an importantsupplementary braking system，Engine Bleeding brake has been applicated widely inforeign countries. It greatly increases the safety of driving. Due to secrecy of theadvanced foreign technology and information,in our country, the utilization level ofdomestic supplementary braking capacity has remained at the exhaust braking phase，the research, production and application of better braking effect and better brakingperformance of engine bleeding brake is still in the early stage, and we are lack ofsystem research on engine bleeding braking performance.The paper based on the internal and external researches,in depth analyzed andresearched the relevant technology of the engine bleeding braking.These provide areference basis for developing independent intellectual property rights and excellentEngine Bleeding braking device.The Engine Bleeding Brake by studied in the paper is based on School and enterprisecooperation projects. The main research work and innovation are as follows：(1)Established engine bleeding brake mathematical model and built athree-dimensional model according to a certain engine prototype， carried onthree-dimensional transient numerical simulation for the process of engine brakeworking, analysed the changes of pition pressure and Braking power in this process.(2)Analyzed the influence of related parameters（including exhaust valve lash，engine speed and exhaust back pressure）on the piston stress and engine bleeding brakeperformance.Analyzed the stress and reliability of key parts of engine bleedingbrake.Ensure that the relevant braking mechanism does not be destroyed in the processof braking performance optimization.(3)The experiments have been carried out to verify the results of numericalsimulation. The results show that the error of experimental value and the simulationvalue error are very small.Simulation calculation method is reasonable and results arebelievable.The Simulation method and conclusions can be used for research of engine bleeding brake design and performance.put forward plans and measures of improvingengine bleeding braking performance according to the results of the study, Improvedengine discouraged braking performance by optimizing the related parameters.