Combustor Stability & Lean Blowout

*University of Dayton, Dayton, OH 45469 The design and development of low-emissions, lean premixed aero gas turbine combustor entail many compromises involving combustor stability, efficiency, pattern factor, and relight capability. In this paper, we report on the combustor performance (efficiency and stability), lean blowout, and emissions of CO and NOx using a well-stirred reactor, bluff body combustor, and a gas turbine combustor. The reactor combustion efficiency was 99 percent over a wide range of mixture ratios and reactor loading and decreased slightly as fuel carbon number increased. A simple global reaction rate analysis provided good predictions of the lean blowout limits. CO emissions reached a minimum at a flame temperature of 1600K and NOx increased rapidly with an increase in flame temperature and moderately with increasing residence time. Detailed kinetic modeling provided satisfactory predictions of CO and NOx emissions. Finally, emissions maps of different combustors demonstrated differences in their emissions performance.