Study Of Methanol Gasoline Adaptive Combustion Control System

In China, methanol gasoline fuel has been widely used on motor engine for its burningutilization, low price and abundant resource. It becomes a new important energy sourcewhich is instead of gasoline after the natural gas. However, there are2problems in theapplication of the methanol gasoline fuel. Firstly, there is not a unified standard for methanolgasoline, which leads that the car engine cannot adjust all kinds of the methanol gasolinewhich is in different proportion. Secondly，it is hard to start at a low temperature when theproportion of methanol is high.First of all, the thesis analyzes the two problems through the different proportionmethanol gasoline’s performance on its alternative of traditional gasoline. First, the reason ofthe current engine can’t adapt to all kinds of proportion of methanol gasoline fuel mix is thatthe original engine ECU adjusting range smaller and existing methanol gasoline controlsystem adjusting range fixed; Second, the engine start difficultly with the high proportionmethanol gasoline fuel at low temperature is because of the methanol’s bad volatilizationcharacteristics compared to gasoline at the low temperature, and it can’t form a highconcentration of mixed gas in the engine cylinder.The second, an adaptive method of controlling the fuel injection quantity is proposed tosolve the problem of that the broadening ratio of the fuel control system is fixed at present.The method makes the engine could control the fuel injection quantity with the engine speedin the process of the start and it realizes the self-adaption of the engine to the methanolgasoline which is in different proportion. A low temperature start module is also designed inthe fuel control system to solve the problem of that it is hard to start at a low temperaturewhen the proportion of methanol is high. This module can adjust engine’s initial injection tothe environment temperature in the process of start. When the environment temperature islow, the module can volatilize excess gasoline and enhance the concentration of the mixedgas in the cylinder through increasing the engine’s fuel injection quantity. It starts the engineat the low temperature successfully with the fuel in which the methanol’s proportion is high.Finally, the experiment on the engine proves that the engine using the control system canadapt the methanol gasoline fuel of different proportion well. Furthermore, the engine can be started successfully at the low temperature with the help of the control system.All the resultsconformance the expectation of the research.