The Design Of The Intake System & The Research On Matching Calibration For LJ276M EFI Gasoline Engine Of ATV

ATV is called All Terrain Vehicle or sand beach automobile which was designed to run in non-highway;it exerts quite important effect in recreation,agriculture, national defence and fire protection field and so on.But almost all the ATV which produced in china are the carburetor fuel supply method and hard to achieve the strict emissions regulations for ATV.By right of the Electronic Fuel Injection Technology can accuracy control the engine air-fuel ratio,they are the essential meassures to satisfy the Euroâ…¢or more higher standard emissions control.According to the using of the motorcycle gasoline engine in our country,a electronic controlled gasoline EFI system was designed and developed by author for the LJ276M ATV gasoline engine,and applied to the original engine.The system which is a speed-density controlled.It has a simple structure,credible performance and cheap cost characteristic.To use the theory of Helmholtz to pre-design the intake system based on the original machine parameters and design requirements of LJ276M gasoline engine.In order to increase intake efficiency of LJ276M EFI gasoline engine,we use GT-POWER to build the whole engine numerical simulation model of the process to analysis the length of the intake manifold which influence the intake efficiency and complete the design and optimization of the intake system.At the same time,the steady-state engine calibration test bench was built.Using Luoyang Nanfeng dynamic test bed as the calibration test bed,with the electronic control systems,emission performance test systems,calibration software and PC,the integrated development environment of Electronic Engine Control is established and finished the calibration of the steady-state conditions of the LJ276M gasoline engine.Based on the study of artificial neural network theory,the paper build an electronic control system parameter model of the steady-state condition to forecast the electronic control parameters by using neural network highly nonlinear mapping ability.This paper completed the RBF neural network structure design and the sample training.The test proved that the model can forecast the electronic control parameters of the steady-state condition accurately.This is a new method to forecast the electronic control parameters of the engine steady-state condition fast and accurately.The engine bench testing and vehicle conditions emission testing proved that the LJM26 electronic control gasoline engine is better than the original carburetor.That the engine maximum power increases by 11%,the maximum torque increase by 9.7%, the minimum fuel consumption decreases by 3%.The emissions with ATV condition are that:co is 1.16g/km,HC is 0,083g/km,NO_x is 0.047g/km.All above is below the critical value of the 30%of Chinaâ…¢.This indicates that the electronic control system has a good technical performance and can greatly improve the engineering level of ATV gasoline engine,so it will have a good application prospect.