Performance and Emission Characteristics of Alcohol/Jet A Blends in a Small-Scale Gas Turbine Engine

Abstract

Gas turbine engines, such as those used in aircraft and stationary power generators, use large amounts of petroleum-based fuel and cause significant air pollution. The desire for energy independence and reduction in pollutant emissions has generated an interest in research on alternate fuels. Alcohols, which can also be derived from biomass, are an attractive energy resource in this regard. However, alcohols have lower heating values than Jet fuels. Hence, the blending alcohol with petroleum fuels seems logical, at least in the nearterm. Therefore, the effects of alcohol/Jet A blends on the performance and emission characteristics of a small-scale 30 kilowatt gas turbine engine were studied. Blends of butanol with Jet A in varying concentrations, ranging from 25 to 100% by volume, were used as fuels. Butanol was chosen in this study because it can be produced from renewable energy sources, such as algae. The performance characteristics including the thrust, thrust-specific fuel consumption, and the emission properties, such as thrust-specific emission indices of CO and NOx, were measured for the different blends and compared with those obtained for Jet A over a range of throttle settings. The operational thrust range of the engine was reduced when compared to that available using Jet A fuel. The NOx emission was lower for the butanol-Jet A blends because of lower temperature at the turbine inlet. The results indicate that n-butanol-Jet A blend is a viable alternative fuel for gas turbine engines.