Performance -emission optimization of a diesel-hydrogen dual fuel operation: A NSGA II coupled TOPSIS MADM approach

A Pareto-based multi-objective optimization approach has been proposed to design and obtain Pareto-optimal set of solutions for performance and emission characteristics of a single cylinder, four stroke diesel engine using hydrogen in dual fuel mode. Instead of defining a single optimal objective, the proposed method establishes the multi-objective model by taking two design objectives into account, which are minimizing load (%) and hydrogen flow rate. To address this optimization problem, we develop a two-stage evolutionary computation approach integrating an exclusive non-dominated sorting genetic algorithm (NSGA-II) and technique for order preference by similarity to ideal solution(TOPSIS). NSGA-II has been utilized to search for the candidate solutions in-terms of both objectives. The obtained results have been obtained as Pareto-front. Subsequently, the best compromise solution has been determined by the TOPSIS method from the Pareto-front according to the decision maker's preference. The design results shows that the proposed approach yields a remarkable reduction in the emission spectra with enhancement in performance of the engine under a single podium obtained by multi-objective optimization.