Approaches to Design of Low-Emission Gas-Turbine Combustion Chambers

The elements and results of a technical approach to the design of low-emission gas-turbine combustors are described. The role of emissions modeling, the major features of an emissions model, the integration of conventional combustor design methodology with an emissions model, and the application of the combined methodology to specific design approaches are examined. The results indicate that emissions models that include nonuniformity of local gas conditions are of immediate utility in the design process, but that further effort in relating this nonuniformity to both conventional design parameters and conventional performance parameters is required. Applications to specific design approaches indicate that very limited emission reduction is obtainable by purely aerodynamic means and that improved fuel injection offers more potential for emission reduction, but that the most stringent emission standards will require either variable-airdistribution or variable-fuel-distribution combustors.