Exergoeconomic analysis of a DI diesel engine fueled with diesel/biodiesel (B5) emulsions containing aqueous nano cerium oxide

The present study was focused on detailed exergoeconomic analysis of a single cylinder DI diesel engine fueled with diesel/biodiesel blend (B5) emulsified with water at different concentrations, i.e., 3, 5, and 7 wt%. Aqueous cerium oxide nanoparticles were also used at two levels (0 and 90 ppm) as a combustion improver. The combustion experiments were conducted under four engine loads in the range of 25-100% of full load condition at a fixed engine speed of 1000 rpm. More specifically, this study was carried out to find the most thermodynamically and economically favorable fuel compositions and engine operating loads. Overall, engine load had a significant effect on the exergoeconomic variables, while fuel type only affected some exergoeconomic parameters. The cost per unit of exergy for the shaft work exergy was considerably decreased by elevating engine load for all the fuel blends investigated. The lowest cost per unit of exergy for the shaft work was determined at 48.81 USD/MJ for neat diesel at full load condition. Although B5W3m was found to be an exergetically and environmentally efficient fuel compared with the other blends, neat diesel was the most exergoeconomically attractive fuel as revealed throughout this study. This meant that one-dimensional criteria solely based on the conventional exergy analysis cannot be used as perfect decision-making paradigms on the efficiency and productivity of internal combustion engines.