STUDY OF PERFORMANCE AND EMISSION CHARACTERISTICS OF A SMALL DI COMPRESSION IGNITION ENGINE USING EMULSIONS

Abstract

Diesel engines exhausting gaseous emission and particulate matter (PM) have long been regarded as one of the major air pollution sources, particularly in metropolitan areas, and these have been a source of serious public concern for a long time. The emulsification method is one of the potentially effective techniques to reduce pollution caused by emission from diesel engines. Water-in-diesel oil emulsified formulations are reported to reduce the emissions of nitrogen oxides (NO,,), carbon monoxides (CO), hydrocarbons (HC), and black smokes without compensating the engine's performance. In this study, mixing emulsification principle was applied to prepare two-phase water-in-oil (W/O) emulsions. Emulsion fuels with varying contents of water and diesel were prepared and stabilized by conventional surfactant named span 80. Surfactant's dosage, emulsification time, stirring intensity, emulsifying temperature and mixing time have been reported. A single cylinder four stroke water cooled, direct injection (DI) type diesel engine was used in this study. Diesel engine performance and exhaust emission was also measured and analyzed with these indigenously prepared emulsified fuels along with neat diesel oil. A comparative study involving torque, brake specific fuel consumption (BSFC), brake thermal efficiency, exhaust gas temperature, hydrocarbon (HC), nitrogen oxides (NO,), carbon monoxides (CO), carbon dioxides (CO2), oxygen (02) emissions and black smoke opacity were also reported for neat diesel and emulsions. It was found that there was a significant benefits associated with the incorporation of water contents in diesel oil regarding environmental hazards. The results indicate that the addition of water in the form of emulsion improved combustion efficiency. The exhaust gas temperature decreased as the percentage of water in the emulsion increased. The brake specific fuel consumption, black smoke opacity, NO.,, HC, CO emissions all decreased as the percentage of water in the emulsion increases