Operating Characteristics of a Natural Gas-Fired Homogeneous Charge Compression Ignition Engine (Performance Improvement Using EGR) 2001-01-1034
Although Homogeneous Charge Compression Ignition (HCCI) engines are expected to attain higher thermal efficiency while reducing NOx emission, the operation performance suffers under high load conditions. In a previous report, we have showed the basic operating characteristics of a natural gas-fired HCCI engine. The present study focuses on the characteristics of HCCI combustion using cooled EGR. It was found that with EGR the load increased by over 20% compared with the previous baseline case. Furthermore, effects of inhomogeneity are investigated by varying EGR supply methods. Inhomogeneous EGR narrows a suitable operation range for EGR and modifies the heat release pattern, indicative of the inhomogeneity to possibly regulate HCCI combustion.