Experimental investigation on lean burn spark ignition engine using alcohol-gasoline blends

Abstract

This study discusses the effects of addition of small amount of alcohols on performance and emission behaviour of a gasoline fuelled lean burn SI engine. Experiments were carried out in a single cylinder diesel engine, which is made to operate as SI engine on lean condition with gasoline as a fuel. The engine was operated at wide open throttle at a compression ratio of 10.5:1 and 1,500 rpm at diverse equivalent ratios by injecting the fuel into manifold. The test outcomes stipulate that use of ethanol-gasoline blend (10% by volume) was better compared with methanol-gasoline blend (10% by volume) and pure gasoline. The test results also revealed that there was 2.5% and 7.5% improvement in brake thermal efficiency with M10 and E10 blends and apparent extension in the lean limit of operation with alcohol-gasoline blends. In emission front, reduction in hydrocarbon and carbon monoxide emissions were observed. However, carbon dioxide and nitric oxide emissions were increased due to better combustion and high in-cylinder temperature. On the whole it is concluded that small alcohol addition to gasoline improves performance and reduce emissions for lean operating SI engine.