EMISSIONS REDUCTION BY VARYING THE SWIRLER AIR-FLOW SPLIT IN ADVANCEDGAS-TURBINE COMBUSTORS

A staged combustor concept for reducing pollutant emissions is current ly under investigation. A numerical study was performed to investigate the chemically reactive flow with liquid spray injection for staged c ombustion. The staged combustor consists of an airblast atomizer fuel injector, a rich burn section, a converging connecting pipe, a quick m ix zone, a diverging connecting pipe and a lean combustion zone. For c omputational efficiency, the combustor was split into two subsystems, i.e., the fuel nozzle/rich burn section and the quick mix/lean burn se ction. The current study investigates the effect of varying the mass f low rate split between the swirler passages for an equivalence ratio o f 2.0 on fuel distribution, temperature distribution, and emissions fo r the fuel nozzle/rich burn section of a staged combustor. It is seen that optimizing these parameters can substantially improve combustor p erformance and reduce combustor emissions. The optimal mass flow rate split for reducing NO(x), emissions based on the numerical study was t he same as found by experiment.