Combustion analysis of the alcohol blended fuels on deposit formation and PM emission in spark ignition engine

Alternative fuels increase fuel economy and lower exhaust emissions in spark ignition (SI) engines. A single-cylinder SI engine operating at 1600 rpm under constant load will have its deposit formation, performance, and particulate matter emissions analyzed using ethanol-gasoline and n-butanol-gasoline blends. The binary blend fuels were gasoline-butanol (85% gasoline, 15% n-butanol) G85nBu15, and gasoline-ethanol (85% gasoline, 15% ethanol) G85E15 are compared with baseline fuel gasoline G100. According to the testing results, the brake specific fuel consumption increased by 0.37% when the G85E15 mix was used. Nevertheless, G85nBu15 improved by 0.47% when n-butanol was added to the mixture and 0.321% for gasoline G100. Due to full combustion of the gasoline-butanol, the BTE for G100 29.5% and G85E15 increased by 31.7%, while the BTE for G85nBu15 increased by 37.3%, which was greater than for gasoline fuel. Energy-dispersive X-ray spectroscopy and scanning electron microscopy were utilized to analyze the elements and identify deposit accumulations. Furthermore, exceptionally long-lasting deposits may result from the heat that modern fuel injection systems produce at and around the exhaust valve. Certain fuels can damage the engine itself, lead to excessive carbon and lacquer buildup, and lower engine performance after prolonged use. The carbon layer percentage on the exhaust valve surfaces of the G100, G85E15, and G85nBu15 is 67.34%, 51.21%, and 25.52%, respectively. In this experiment, there was very little exhaust valve deposit for the gasoline G85nBu15. Compared to ethanol/gasoline, a gasoline-ethanol-n-butanol blend fuel generated less particles. Compared to pure gasoline, the n-butanol/gasoline mix produced 10–15% lower PM 1 , PM 2.5 , and PM 7 emissions, which are important for air pollution brought on by fine/very fine particles.