Evaluation of Operational and Environmental Indicators of Automobile Gas Piston Engines by Means of Mathematical Modeling

Automobile engines are the main source of harmful emissions into the atmosphere in large cities. These engines use gasoline or diesel fuel. The efforts of many scientists are aimed at developing measures to reduce the impact of gasoline engines on the environmental situation. Conversion of gasoline engines to gaseous fuel (methane) is considered in this article as an effective way to improve the environmental performance of automobile engines. An overview of research on this topic is given. The article provides a description of the technical characteristics for two gasoline engines that are converted to work on methane. The study was carried out on the basis of mathematical modeling of the engine operating cycle in the Diesel-RK program. A brief description of the mathematical model is presented. It is shown that the conversion of gasoline engines to methane leads to a decrease in power within 7.5% while simultaneously reducing the specific fuel consumption by up to 12%, and there is also a decrease in NOx emissions by 2-3 times. It has been established that the compression ratio of a methane engine has a significant impact on the technical and economic indicators. It was revealed that an increase in the compression ratio to 15 leads to an increase in the power of the gas piston engine to the level of a gasoline engine. At the same time, fuel consumption is reduced by up to 20%, and improved environmental performance is observed in comparison with a gasoline engine.