Selection of Diesel Fuel Alternatives for Compression Ignition Engines: A Hybrid Multiple-criteria Decision-Making Approach

This study delves into the quest for sustainable diesel fuel alternatives, evaluating five prominent options: vegetable oils, biodiesel, hydrotreated vegetable oil (HVO), emulsions, and alcohols. The research employs a hybrid multiple-criteria decision-making (MCDM) approach, utilizing three distinct methods—ARAS, TOPSIS, and VIKOR—to rank these alternatives based on their performance and emission characteristics. Key performance indicators include brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), and emissions of nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HC), and smoke. The study finds that HVO emerges as the top-performing alternative, offering enhanced thermal efficiency and reduced emissions compared to conventional diesel. Emulsions follow closely, showcasing significant emission reductions but facing challenges related to increased fuel consumption. Alcohols, while reducing smoke emissions, exhibit higher fuel consumption and lower thermal efficiency. Biodiesel blends demonstrate reduced HC and smoke emissions but struggle with increased NOx emissions and fuel consumption. Vegetable oils, despite their environmental benefits, significantly impact engine performance, particularly brake thermal efficiency. The consistent ranking of HVO across all MCDM techniques underscores its potential as a superior diesel alternative. This comprehensive analysis provides valuable insights for professionals seeking to optimize engine performance and reduce environmental impact through the use of alternative fuels.