The Research Of The Effects Of Alcohol Fuel On The Single-cylinder Two-stroke Gasoline Engine

The single-cylinder two-stroke gasoline engine is widely used in China, but its drawbacks are the higher fuel consumption rate and serious pollution emissions. For improving its capability, the experts have been doing extensive researches on the structure of the single-cylinder two-stroke gasoline engine, while there is still no research on using alcohol fuel as the alternative fuel, not even using it in the two-stroke gasoline engine. In order to solve the problems above, in this essay the research is done on using alcohol fuel in two-stroke gasoline. Through experiments, the effects of alcohol fuel on the performance of the single-cylinder two-stroke gasoline engine, which is currently in use, are researched. According to engine performance evaluation indexes, external features, such as output torque, output power, rotation speed and specific fuel consumption, partial characteristic and fuel consumption and emission characteristic are tested through the experiments of burning the mixtures of alcohol and gasoline which are in different groups of proportion. The different groups of measurement results are compared.The analysis of the experimental results shows that when it is burning the mixture of gasoline and a lower proportion of alcohol, the power performance and fuel economy of the single-cylinder two-stroke gasoline engine are improved on most of the rotation speeds, With the increasing concentration of alcohol added fuel, the engine power of first increase then decreased.Through data fitting analysis, and validated test verification, it is identified that,when the ethanol concentration is 4%, the power performance and economic performance of the single-cylinder two-stroke gasoline engine are best; When the methanol concentration is 18%, the power performance and economic performance of the single-cylinder two-stroke gasoline engine are best; meanwhile, burning the fuel mixture of alcohol and gasoline reduces the contents of HC and CO in the exhaust of single-cylinder two-stroke gasoline engine, thereby improving the exhaust emissions condition. When the blending concentration is less than 20%, with the increasing concentration of alcohol, the HC and CO contents are significantly reduced.