Study on the Influence of Ignition Timing on the Combustion and Emission of the Methanol Direct Injection Spark Ignition Engine at Idle Condition

The transportation industry in China accounts for approximately 60% of the country’s total oil consumption. The transportation sector, which is highly dependent on oil, has become the industry with the fastest growth in greenhouse gas emissions in China. Reducing carbon emissions in the transportation sector is a key path for China to achieve carbon peaking and carbon neutrality. Choosing alternative energy sources in the post-oil and gas era has become an important topic. Methanol is the fourth most produced basic chemical raw material in the world and has a wide range of sources. The selection of methanol as an alternative fuel in the transportation sector is also an objective requirement of China’s resource endowment, industrial structure and geographical and climatic conditions. The paper studies on the Influence of ignition timing on the combustion and emission on the idle condition of homogeneous and stratified mode. The main conclusion as follow: PMAX and HRRMAX increase monotonically, and the timings of PMAX and HRRMAX move towards the compression top dead center, as the ignition timing advances. The combustion duration becomes longer as the ignition timing advances in both modes. The coefficient of variation of IMEP and ITE is very low at the idle condition in both modes. The CO and HC emissions in the stratified mode are higher than those in the homogeneous mode, but the trend of NOx emission is opposite. The methanal emission increases as the ignition timing advances in both modes.