Multi-objective sustainable energy assessment of a hydrogen-assisted PCCI engine fuelled with Millettia Pinnata oil–camphor oil blend

This study offers a thorough assessment of a hydrogen-assisted premixed charge compression ignition (PCCI) engine powered by a renewable oil blend. The engine characteristics wereevaluated utilizing the energy, exergy, and emission dimensions. Response Surface Methodology (RSM) was utilized to model and analyse engine responses under diverse operating circumstances. The TOPSIS method was employed to determine optimal operating parameters via multi-criteria decision-making. The main objective of this study is the impact of H₂ gas inclusions on a compression ignition (CI) engine powered with Millettia Pinnata oil and a Millettia Pinnata-camphor oil blend. A central composite matrix with primary injector fuel of Millettia Pinnata oil and an evenly mixed Millettia Pinnata-camphor oil designs two experimental matrices using loading percentage (50 to 100%) and H₂ gas induction rate (0 - 10 LPM). The experiment is carried out on a 4-stroke computerized single-cylinder water-cooled CI engine. The addition of H₂ gas to the Millettia Pinnata-camphor oil blend enhances thermal efficiency, exergy efficiency, and sustainability index. It also lowers volumetric efficiency, brake-specific hydrocarbon emissions, brake-specific carbon monoxide emissions, smoke opacity, and brake-specific carbon dioxide emissions. However, brake-specific nitric oxide emissions increase. The addition of H₂ gas improves all parameters except brake-specific nitric oxide emissions. Therefore, exhaust gas must be treated using an SCR technique.