Production and utilization of hydrogen enriched fifth generation biofuel in LTC engines with reformed EGR.

The increasing global demand for cleaner energy solutions highlights the need to combine hydrogen with advanced biofuels for use in low-temperature combustion (LTC) engines. This study experimentally investigates the performance and emissions of an LTC engine fueled with six test fuels: Diesel, Citronella biofuel, three hydrogen-enriched blends (H20, H40, H60) and H40E (H40 + 10%R-EGR). Among the tested fuels, the H40 blend demonstrated the highest brake thermal efficiency (BTE), surpassing that of conventional diesel. Emission analysis showed notable reductions in hydrocarbons (HC) by 65%, carbon monoxide (CO) by 37%, carbon dioxide (CO₂) by 8%, NOx by 6%, and smoke opacity by 20.8% compared to diesel. Notably, H40E further lower NOx formation by 3% than H40 but HC and CO were higher by 2 to 5%. Combustion analysis revealed that hydrogen enhanced pre-mixed combustion, resulting in improved in-cylinder pressure and heat release rate. The experimental results were validated using Sankey diagram visualization, confirming improved energy distribution. The findings indicate that hydrogen-enriched biofuels, particularly the H40 blend offer a promising pathway for cleaner and more efficient engine operation, supporting the global transition away from fossil fuels.