Energy, exergy, emissions and sustainability assessment of hydrogen supplemented diesel dual fuel turbocharged common rail direct injection diesel engine

The present investigation involves the study of Mahindra & Mahindra Supro BS VI Twin Cylinder Turbocharged CRDI Diesel Engine modified to operate under dual fuel mode utilizing hydrogen as a secondary fuel and neat diesel as a pilot fuel. The tests were carried out at constant speed of 2200 rpm (±20 rpm) under three different loading conditions i.e. BMEP values of 1.38 bar, 3.47 bar and 5.6 bar using H2 enrichment of 0%, 10%, 20%, 30% and 40% respectively along with neat diesel. The performance characteristics of the engine are evaluated using energy-exergy and emissions-based approach along with sustainability studies. The results show that turbocharging significantly improves volumetric and indicated thermal efficiency of engine. At BMEP of 5.6 bar, D + H2 (40%) exhibited highest energy efficiency of 28.94% and exergy efficiency of 28.41% compared to baseline diesel fuel. The irreversibilities due to combustion, mixing, friction and unaccounted reasons was found to be the minimum for D + H2 (40%) at higher BMEP values. Emission analysis revealed that trade-off takes place between nitrogen oxides and smoke opacity (%) with hydrogen substitution to baseline diesel fuel. The sustainability analysis revealed that, D + H2 (40%) has the highest exergy performance coefficient and sustainability index compared to all other cases. From the results, it can be concluded that D + H2 (40%) is the most suitable fuel combination for the Twin Cylinder Turbocharged CRDI Diesel Engine.