Investigation of biodiesel blends and hydrogen addition effects on CI engine characteristics through statistical analysis

This study investigates the performance, combustion, and emission characteristics of a single-cylinder compression ignition engine fueled with blends of Soy methyl ester (BS100) and macauba methyl ester (BM100) biodiesels, with hydrogen addition. Biodiesel blends (BSM10 - BSM50), and hydrogen addition (2-5%) were tested at various engine loads and speeds. The optimal blend, BSM20 (80% BS100 + 20% BM100), showed up to 7.8% higher brake thermal efficiency and 6.2% lower brake-specific fuel consumption than diesel. Emissions were significantly reduced: NOx by 12.9%, HC by 22.4%, CO by 27.5%, and smoke opacity by 18.7%. Adding 5% hydrogen to BSM20 further improved performance, reducing fuel consumption by up to 3.1% and increasing thermal efficiency by 2.5%, with substantial reductions in hydrocarbon and carbon monoxide emissions. This investigation highlights the potential of sustainable biodiesel blends and hydrogen as viable alternatives to conventional diesel fuels, offering significant environmental benefits and enhanced engine performance.