Study On The Matching Technology Of Electric Control Motorcycle For China Stage-Ⅳ Standard

With the increasing number of motorcycles in China,the emission of motorcycle tail gas continues to rise,which has a huge impact on the sustainable development of China’s ecological environment and economy.To solve this problem,Chinese government has promulgated a new motorcycle emission standard called China stage-Ⅳ standard.It is based on the situation of China’s motorcycle industry,and it is adapted from GTR2 and EU regulations.Now motorcycle manufacturers need to design a new motorcycle calibration technology program so that the new products can come up to the new emission standard.This study comes up with a calibration program that combines with computer simulation and calibration testing.This thesis takes a single-cylinder gasoline engine that produced from China as the research object.Compare with the old standards,the new emission standard is much stricter and has more technology requirement.It stipulates that new products must meet the emission limits and fatigue durability requirements.By reading a lot of literature,this thesis studies the engine and vehicle calibration technology,the application of computer simulation as well as the muffler fatigue durability analysis.The simulation model is established and calibrated.The map of fuel inject pulse width and ignition advance angle will be used for the later optimization and comparative analysis.At the same time,using the computer simulation and orthogonal experiment analyses the effect of the engine emissions by the engine electric control parameters.And then the study establishes an prediction model by using BP neural network.This model optimizes the optimal ignition advance angle and pulse width MAP obtained by simulation.The optimized data will be used to compare with the test data.The calibration of steady state for this single-cylinder gasoline engine is carried out.This experiment obtains the MAP of ignition advance angle and pulse width.By comparison,the results of simulation and optimization are validated and these are more accurate.The motorcycle emission test with WMTC cycle proves that the emission performance of the vehicle after calibration meets the emission limit of motorcycle standard.For meeting fatigue durability requirements,this study uses finite element method to finish the muffler analysis of thermal fatigue.The CATIA and Hypermesh is used to establish and pretreat the model.In order to ensure the reliability of the model,the modal analysis and modal test are carried out.At the same time,CFD analysis proves that muffler meets the normal design requirements.At last,the thermal stress fatigue analysis of muffler is finished by ABAQUS and FE-SAFE software.This thesis proves that the computer simulation can effectively assist the calibration of the motorcycle engine,while the finite element analysis shows that the thermal fatigue of the muffler meets the durability requirements.So this method can effectively alleviate the problem about long time and high cost of traditional calibration test and endurance test.