PERFORMANCE AND EMISSION CHARACTERISTICS OF A PARTIALLY CERAMIC COATED DIESEL ENGINE USING WATER DIESEL EMULSION

The performance and emissions of an engine can be improved by accelerating the mixing process. This can be achieved by secondary atomization (micro explosion) and hot (ceramic coated) combustion chamber. An attempt was made to study the effect of water diesel emulsion on a ceramic coated [plasma sprayed zirconia (PSZ) coated cylinder head and valve faces] diesel engine. 5% decrease in brake specific fuel consumption (BSFC) for 10 volume percent of water in the case of conventional engine and a 21% decrease in BSFC for 18 volume percent of water in water diesel emulsion in the case of partially ceramic coated engine (BSFC, for 15 and 18 volume percent of water in emulsion, being same) was obtained compared to conventional engine fueled with neat diesel at 100% load. Hence, ceramic-coated engine permits use of 8% more water in water-diesel emulsion. Partially ceramic coated diesel engine for neat diesel has shown marginal decrease in BSFC at higher loads and no change at lower loads. Exhaust gas temperature (EGT) decreased throughout the entire load range and it was marginally higher for coated engine compared to conventional engine. A 29%, 21% and 40% reduction in CO, SD and NO_x emission was obtained in case of ceramic coated diesel engine corresponding to 18 volume percent of water in emulsion compared with conventional engine fueled with neat diesel at 100% load.