Abstract
Experimental and theoretical studies with oxygenated fuels have demonstrated large decrease of soot emissions, which correlated well with the fuel oxygen content. Reduction of CO and HC emissions with oxygenated fuels was also obtained. However, penalties in both BSFC and NOx emissions have been observed with oxygenation of diesel fuels. Hence, it is necessary to weigh the tradeoffs in power output and in the emissions of various pollutants. Ceramic coatings have application as thermal barriers to improve the efficiency of the engines, by reducing energy loss and cooling requirements with acceptable reductions in emissions except NOx. Use of EGR causes a sharp reduction of NOx and smoke simultaneously on the oxygenated fuels. On the other hand, EGR results to a slight reduction of engine efficiency and maximum combustion pressure which in any case does not alter the benefits obtained from the oxygenated fuel. 1, 4 dioxane, normally called as dioxane is an ether, miscible in diesel has favorable properties as an alternative or additive for diesel fuels. In previous studies, the present research team investigated dioxane as an additive to stabilize diesel ethanol blend as it allows the splash blending of ethanol in diesel in a clear solution, with the aim of improving the performance and emission characteristics, and found an optimum composition of dioxane – ethanol with diesel showed high efficiency with reduced emissions for a thermal barrier coated engine with EGR than a normal diesel engine. They also found direct dioxane diesel blends also gave comparable results with diesel on a standard engine. This manuscript presents a comparative evaluation of dioxane as an alternate fuel and an additive with ethanol on a standard diesel engine, Zirconia Alumina (PSZ) coated engine, and coated engine with EGR regarding engine performance characteristics and environmental repercussions. Results have shown that the performance and the impact on pollutant emissions may be comparable in all conditions of the engine on both fuel cases.
Keywords: Oxygenated fuel, Thermal barrier coating, Exhaust gas recirculation, Performance and emission parameters