فهرست نشریات علمی دسترسی آزاد ایران

This study explores a novel technique for carbon deposit removal in diesel engines, particularly affecting agricultural machinery, through the injection of steam combined with nanoparticles. The accumulation of carbon deposits decreases engine performance and escalates thermal stress. The proposed method involves injecting steam into the combustion chamber, where it interacts with the deposits, aided by microwave action, to effectively eliminate them. An experimental setup was created alongside a standard power supply to assess performance improvements. Results indicate significant enhancements in diesel engine function: a power increase of up to 15% for older machinery, a reduction in specific fuel consumption by up to 18%, and a decrease in exhaust soot content by as much as 14%. Additionally, the study incorporated magnetite nanoparticles (Fe₃O₄) at concentrations of 0, 25, and 50 ppm, examining their effects in a full-factorial test setup with varying steam mass fractions and operational conditions. The findings showed that Fe₃O₄ reduced soot emissions significantly of 12.4% at 25 ppm and 20.1% at 50 ppm, without impacting effective power. Minor improvements in fuel consumption of -1.1% and -1.8% were noted at the respective nanoparticle concentrations. Endurance tests confirmed cleaner injectors and reduced in-cylinder deposits, with specific reductions of 19% in piston crown deposits and 28% in coking index at 50 ppm. No stability or filtration issues arose, identifying an optimal operational region at steam mass fractions between 12-18%, 50 ppm of Fe₃O₄, and engine speeds of 1300-1500 min⁻¹, which collectively minimized soot and specific fuel consumption while maintaining power levels.