The Analysis On Ignition Timing Of The Car Engine Which Burning Gasohol

The energy shortages and environment friendly are two fundamental realities of the country, in this paper, the realism, feasibility and necessity to promote the use of gasohol in our country are in-depth analyzed. For the ethanol, it has a good intermiscibility with gasoline, when applying to the gasoline engine, the compression ratio can be improved for its higher octane rating. Also, its high vaporization and latent heat can reduce the temperature in engine cylinder, which improving the charging efficiency better; however, some factors may make parts of the engine performance become poorer. One of the important factors is the change of advanced ignition angle, which is caused by the great difference between ethanol and gasoline in their physical and chemical properties.The size of advanced ignition angle has an important impact on the arriving moment of maximum explosive pressure in cylinder, as well as the engine final effective power.In order to improve the engine performance on burning gasohol, a series of bench tests about E10、E20and gasohol have been performed, then the engine’s performance index under certain condition, including power, economy and emission were measured, also the advanced ignition angle was measured under different condition.The paper introduces the establishment of the engine working model, which including intake system, exhaust systems, the cold, turbochargers and engine. The performance parameters in cylinder during the process of modeling were calculated, as well as the convergence standard and boundary conditions were set. At last, the engine simulation model was established combined with the calculation results and engine structure parameters.The parameters’ optimization calculation of ignition timing was processed on the qualified model. After optimizing, the changes of engine performance indicate that the economy and dynamics performance become well if the ignition timing earlier than before, Whereas the emissions become worse, but in reverse if ignition timing later. In this paper, the dynamic and economy are the main objective. According to this principle, the corresponding control strategy is established which will provide certain reference basis for the theoretical research of the electron-controlled engine.