EXPERIMENTAL INVESTIGATIONS OF DIESEL-EMULSIONS AS FUEL IN SMALL DIRECT INJECTION CI ENGINES

Abstract

The emission of pollutants especially particulate matter and nitrogen oxides, generated by the operation of a diesel engine, poses a threat to the ecology of our planet and is detrimental to human health. The application of an emulsification technique to prepare the fuel has been considered to be one of the possible approaches to reduce the production of diesel engine pollutants, as well as the rate of fuel consumption. Water-in-diesel oil emulsified formulations are reportedto reduce the emissions of nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxides (CO), black smokes and particulate matter (PM) without compensating the engine's performance. A single cylinder diesel engine study of water-in-diesel emulsions was conducted to investigate the effect of water emulsification on the engine performance and emissions. Emulsified diesel fuels of 0, 5, 10, 15 and 20 water/diesel ratios by volume, were used in a single cylinder, direct injection diesel engine, operating at 1500-2700 rpm. A comparative study involving speed, brake specific fuel consumption (BSFC), brake thermal efficiency, exhausts gas temperature, hydrocarbon (HC), nitrogen oxides (NOx), carbon monoxides (CO), carbon dioxides (CO2) emissions and black smoke opacity were reported for neat diesel oil and emulsions. The results show that there was a significant benefits associated with the addition of water contents in diesel oil. The obtained experimental results indicate that the addition of water in the form of emulsion improves brake thermal efficiency. On the whole it is concluded that brake specific fuel consumption, exhaust gas temperature, NOR, HC, CO, CO2 and black smoke opacity decrease as the percentage of water in the emulsions increases.