Research on Gasoline Homogenous Charge Compression Ignition (HCCI) Engine

Abstract

Homogenous charge compression ignition engine (HCCI) represents a new idea of combustion technology that combines the main advantages of the gasoline engines (the homogeneous charge) with the main advantages of the diesel engines (higher compression ratios which determinates higher efficiencies). An important advantage is the low temperature combustion that offers higher thermal efficiency and lower emissions of Nitrogen Oxides (NOx) and Particulate Matter (PM) in comparison to spark ignition and diesel engines. For such engines, a major problem is to control the start of the combustion because the air and fuel need to be mixed homogeneously before the starts of combustion and, the air fuel mixture auto ignite due to the temperature increasing at the end of compression stroke. This paper presents the work to develop a HCCI engine starting from a spark ignition engine platform, for this the engine was modified as follow: the carburetor was replaced by a fuel injection system, the compression ratio was increased, and variable valve timing was introduced. The research work was focused on to determine the parameters which control the combustion timing o. HCCI engine to obtain the best energetic and ecologic parameters.