SAE International Performance and Emission Characterization of 1.2L MPI Engine with Multiple Fuels (E10, LPG and CNG) 2010-01-0740

Most of the energy consumed in today's mobility industry is derived from fossil fuels. The demand for clean, renewable and affordable alternative energy is forcing the automotive industry to look beyond the conventional fossil fuels. Fuels options like liquefied petroleum gas (LPG), compressed natural gas (CNG) and ethanol blends are quickly finding widespread acceptance as alternative sources. This paper presents the results of experimental studies conducted on a 1.2-liter MPI engine with three different alternate fuels. The fuels considered for the evaluation (apart from base gasoline) are 10% ethanol-blended fuel (E10), LPG (gaseous propane: butane mix) and CNG (gaseous methane). Experiments were conducted to compare their effect on engine performance and emissions. The test results show that E10 has the lowest power drop whereas CNG has the highest power drop (12%) as compared to gasoline. The maximum power drop in LPG is 4%, which is close to the theoretical predictions. Compared to gasoline, there is no major deterioration in low end and maximum torque with E10 and LPG. The usage of E10 required minimum engine hardware changes (restricted to fuel lines). The carbon dioxide (CO\u2082) emission in LPG mode was found to decrease by 11% compared to 23% in CNG. The amount of carbon monoxide (CO) and hydrocarbon (HC) emissions in LPG and CNG modes were found to be a function of the gasoline to gas transition temperature (with gasoline as the starting fuel). Compared to gasoline, both the gaseous fuels resulted in higher nitrogen oxide (NOx) emissions. Emission tests with neat gasoline and E10 blend shows a net decrease in diluted CO and HC emissions by 13% and 19% respectively with E10 blends. On the other hand, NOx emissions increased by 16%. There is a net reduction in CO\u2082 by 2% compared to neat gasoline.