抄録
Many research institutes are pursuing research on homogenous-charge compression ignition (HCCI) engines, which offer higher thermal efficiency than gasoline engines at low and medium loads and produce fewer emissions than diesel engines. However, the ability of HCCI engines to operate at high loads is limited by the rate of pressure rise rate and knocking, while their ability to operateat low loads is limited by combustion efficiency.
This article describes the basic characteristics of HCCI engines running on natural gas, and technologies for increasing their output. Natural gas has a higher ignition temperature than gasoline or light oil, generally around 1050K. Supercharging was found to be an effective way of increasing output, and a brake mean effective pressure of 0.98 MPa, thermal efficiency of 43.3% and NOx emissions concentration of13. 8ppm were obtained with a 4-cylinder gas engine.
