Emissions Performance Study of Oxygen-Enriched Combustion on Spark-Ignition Engine at Cold-Start

Based on the reaction chemical stoichiometric, oxygen-enriched combustion was studied on the spark-ignition engine at cold-start. Pollutants formation and models were proposed, to study the power performance and emission performance of spark-ignition engine, which would be affected by the oxygen concentration in the air entered into the engine. The models were used to analyze the emissions of oxygen-enriched combustion on spark-ignition engine. Experimental investigation was carried out to validate the theoretical analysis. Results showed that as the oxygen concentration in the intake air was increased, the emissions of CO and HC were decreased, but NO was increased.