A hybrid method of modified NSGA-II and TOPSIS to optimize performance and emissions of a diesel engine using biodiesel

• Published in: Applied thermal engineering Vol. 59; no. 1-2; pp. 309 - 315
• Main Authors: Etghani, Mir Majid, Shojaeefard, Mohammad Hassan, Khalkhali, Abolfazl, Akbari, Mostafa
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 25.09.2013; Elsevier
• Subjects: Algorithms; ANN; Applied sciences; Biodiesel; Blends; Brakes; Castor oil biodiesel; Emissions; Energy; Energy. Thermal use of fuels; Engines and turbines; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Heat transfer; Learning theory; Mathematical models; Neural networks; NSGA-II; Optimization; Theoretical studies. Data and constants. Metering; TOPSIS; ANN; NSGA-II; Castor oil biodiesel; Performance; TOPSIS; Emissions; Diesel fuel; Diesel engine; Biofuel; Biodiesel
• ISSN: 1359-4311
• DOI: 10.1016/j.applthermaleng.2013.05.041

This paper addresses artificial neural network (ANN) modeling followed by multi-objective optimization process to determine optimum biodiesel blends and speed ranges of a diesel engine fueled with castor oil biodiesel (COB) blends. First, an ANN model was developed based on standard back-propagation algorithm to model and predict brake power, brake specific fuel consumption (BSFC) and the emissions of engine. In this way, multi-layer perception (MLP) network was used for non-linear mapping between the input and output parameters. Second, modified NSGA-II by incorporating diversity preserving mechanism called the ε-elimination algorithm was used for multi-objective optimization process. Six objectives, maximization of brake power and minimization of BSFC, PM, NOx, CO and CO2 were simultaneously considered in this step. Optimization procedure resulted in creating of non-dominated optimal points which gave an insight on the best operating conditions of the engine. Third, an approach based on TOPSIS method was used for finding the best compromise solution from the obtained set of Pareto solutions. •Effects of castor oil biodiesel blends have been examined on the diesel engine performance and emissions.•Modeling engine performance and emissions by artificial neural network with back-propagation algorithm accurately.•2 and 6-objective optimization has been applied by the modified NSGA-II.•Trade-off optimum design points are determined by applying TOPSIS.