Impact of Biodiesel on Fuel Preparation and Emissions for a Liquid Fired Gas Turbine Engine

Abstract

This paper reports the fuel injection, vaporization, and emissions characteristics when running a 30 kW gas turbine engine on biodiesel (B99), and diesel fuel distillate # 2. Compositional analysis is used to assess the distillation of these fuels and a comparison is made with ethanol. The role of the liquid properties on fuel preparation and the subsequent engine performance is also assessed. The results show that while compositionally simple, biodiesel features some properties that result in inferior atomization and longer evaporation times compared to DF2. In addition, the overall spray behavior differs substantially in terms of density and width. The measured NO and CO emissions levels produced by the engine reveal significant increases with the use of biodiesel which is expected given the inferior fuel preparation characteristics. It appears reasonable to modify the fuel injector in order to overcome the deleterious effects observed for biodiesel. The benefits of blending biodiesel and ethanol in order to eliminate duel fuel operation during cold startup are discussed.