EXPERIMENTAL STUDY ON DUAL-FUEL OPERATION OF HYDROGEN AND DIESEL IN CI ENGINES
Abstract
This current study examines the effects of the use of hydrogen gas as well as nanoparticle additives on the performance, combustion, and emission characteristics of a compression ignition (CI) engine. A fixed flow rate of 2 L/min of hydrogen gas was supplied to the system, and concentrations of 25, 50, and 75 ppm of nanoparticle additives were employed. Engine performance was determined by measuring the Brake Specific Energy Consumption (BSEC) and Brake Thermal Efficiency (BTE), while the combustion efficiency was analyzed through the cylinder pressure and heat release rate (HRR). The emissions parameters of CO, HC, NOx, and Smoke opacity were also tested at varying loads of engine operations. The findings of this experimental study demonstrate significant improvement in combustion efficiency and engine performance from hydrogen gas enrichment as well as nanoparticle additives. The fuel blend with the highest BTE and lowest BSEC was H₂ at 2 L/min + 75 ppm. The combustion analysis showed that the maximum heat release rate increased from 45 J/°CA to 82 J/°CA and the maximum cylinder pressure for diesel increased from 68 bar to 90 bar. The system was supplied with hydrogen gas at a set flow rate of 2 L/min, and concentrations of 25, 50, and 75 ppm of nanoparticle additives were utilized. Significant reductions in CO, HC, and smoke opacity were achieved due to the increased combustion and oxidation processes within the fuel blends. Under full load, there was about a 30%, 24%, and 36% reduction in CO, HC, and smoke opacity, respectively. However, NOx emissions increased as a result of the increased temperatures in the cylinder due to effective combustion. Generally, the results indicated significant improvements in combustion efficiency as well as reductions in incomplete combustion pollutants due to the combination of hydrogen and nanoparticles. Based on the results, H₂ at 2 L/min + 75 ppm gave the best blend in terms of emission reductions and increased efficiency.