Performance–exhaust emission optimization of compression ignition engine under E-Dime strategies

The present study highlights the inherent capabilities of ethanol-derris indica methyl ester (E-Dime) blends on performance and exhaust emission profiles of an existing compression ignition (CI) engine. Ethanol incorporation to Dime significantly reduces cumulated oxides of nitrogen and unburned hydrocarbon (NOHC) and particulate matter (PM) emissions of the CI engine along with improvement in brake thermal efficiency (Bth) and brake specific energy consumption. To this end, a multi-objective genetic algorithm (MOGA)-II is introduced to reveal Pareto solutions of the CI engine under the forthcoming Environmental Protection Agency Tier 4 exhaust emission mandates. Moreover, a multi-attribute decision-making-based technique for order preference by similarity to ideal solution (TOPSIS) is also introduced to pick out the optimal operating conditions of E-Dime blends. The MOGA-II-assisted TOPSIS-based trade-off investigation uncovers the optimal decision variables of 4.2 bar BMEP, 79.82% (by volume) biodiesel share and 20.18% (by volume) ethanol share with corresponding objective variables of 29.85% Bth, 0.645 g kW−1 h−1 NOHC, 0.523 g kW−1 h−1 carbon monoxide (CO) and 0.254 g kW−1 h−1 PM. The validation of the optimized results against the experimental one indicates a very lower deviation along with praiseworthy composite desirability of 0.972.