Emission and Performance of a Lean-Premixed Gas Fuel Injection System for Aeroderivative Gas Turbine Engines
A dry-low-NOx, high-airflow-capacity fuel injection system for a lean-premixed combustor has been developed for a moderate pressure ratio (20:1) aeroderivative gas turbine engine. Engine requirements for combustor pressure drop, emissions, and operability have been met. Combustion performance was evaluated at high power conditions in a high-pressure, single-nozzle test facility, which operates at full base-load conditions. Single digit NOx levels and high combustion efficiency were achieved. A wide operability range with no signs of flashback, autoignition, or thermal problems was demonstrated. NOx sensitivities to pressure and residence time were found to be small at flame temperatures below 1850 K (2870°F). Above 1850 K some NOx sensitivity to pressure and residence time was observed and was associated with the increased role of the thermal NOx production mechanism at elevated flame temperatures.