Reduction of NO(x) by fuel-staging in gas turbine engines: A commitment to the future

As part of an ongoing program of continuous improvement by control of gaseous emissions from the combustors of gas turbines, a unique fuel-staged annular combustor is being developed for application to current and future Pratt & Whitney aircraft engines. The configuration advantages of this combustor are outlined, and discussions are presented on staging considerations and fuel system impacts. Development of the fuel-staged combustor is described by reference to supporting mixing experiments and computational fluid dynamic studies, and rig tests at high pressures. Measured results are given appropriate for the International Aero Engines (IAE) V2500 engine that show progressive reductions in achieved emissions compared to the goals established for this program.