A Kinetics Study on NO_x Emission of an Axially-staged Gas Turbine Combustor

A chemical reactor network (CRN) model was established for the axially-staged combustor to study the effects of following key staging parameters on the NO_x emission under typical operating conditions of advanced gas turbines, such as the fuel split, residence time split and flow rate split between the two stages. Results show that under constant exit temperature of combustor, the NO_x emission could be reduced significantly when running the second stage hotter than the first one, by splitting more fuels to the second stage, and/or by shortening the residence time in the second stage through adjusting the layout of the second stage nozzles. In addition, poor mixing of the first-stage combustion products with the second stage mixture of fuel and air would remarkably affact the NO_x emission reduction of the staged combustion system.