Performance and combustion characteristics of alcohol-gasoline blends at wide-open throttle

This study discusses the performance and exhaust emissions of a vehicle fueled with low content alcohol (ethanol and methanol) blends and pure gasoline. The vehicle tests were performed at wide-open throttle and at vehicle speeds of 40 km h(-1), 60 km h(-1), 80 km h(-1) and 100 km h(-1) by using an eddy current chassis dynamometer. The test results obtained with the use of alcohol-gasoline blends (5 and 10 percent alcohol by volume) were compared to pure gasoline test results. The test results indicated that when the vehicle was fueled with alcohol-gasoline blends, the peak wheel power and fuel consumption slightly increased. And also, in general, alcohol-gasoline blends provided higher combustion efficiency compared to pure gasoline use. In exhaust emission results, a stable trend was not seen, especially for CO emission. But, on average, alcohol-gasoline blends exhibited decreasing HC emissions. In 100 km h(-1) vehicle speed test, the alcohol-gasoline blends provided lower vehicle performance and lower NOx emission values compared to pure gasoline. At all vehicle speeds, minimum CO2 emission was obtained when 5% methanol was added in gasoline. The low content alcohol blends did not reveal any starting problem, or irregular operation on the engine. (C) 2011 Elsevier Ltd. All rights reserved.