The present disclosure relates to a fuel-air premixer for a turbine system. The fuel-air premixer includes a swirler and a centerbody. The swirler is configured to direct a flow of air through the premixer, and the centerbody is configured to inject fuel into the flow of air. Additionally, the centerbody includes an airfoil shape that reduces and/or substantially eliminates recirculation pockets to prevent autoignition and/or flame holding in a combustion chamber. Accordingly, the turbine system may produce fewer NO.sub.x emissions.

A fuel injector includes a central member arranged on axis of fuel injector and a first member arranged around central member. A first swirler is arranged between central member and first member. A pilot fuel injector is arranged to supply fuel onto inner surface of first member. A second member is arranged between downstream end of first member and downstream end of shroud. A second swirler is arranged between upstream end of first member and upstream end of shroud and between downstream end of first member and upstream end of second member. A third swirler is arranged between downstream end of shroud and second member. A main fuel injector is arranged to supply fuel into an annular passage between first member and second member and a fourth swirler extends through first member.

A burner includes a pilot burner, a combustion chamber, and a swirler located radially outwardly of the combustion chamber and being adapted to impose a swirling motion on a fuel/air mixture about an axial centerline of the combustion chamber. The pilot burner has a pilot burner face located radially inwardly of the swirler and forms an axially upstream wall of the combustion chamber, the pilot burner face incorporating a pilot fuel injector and an ignitor, both being positioned radially offset from the axial centerline. A recess is positioned radially offset from the axial centerline within the pilot burner face.

A fuel injector for a combustor generally includes an annular outer body having an inlet and an outlet. The outer body at least partially defines an outer flow passage. An inner flow passage extends at least partially through the outer flow passage and a radial swirler is disposed at the inlet of the outer body. The radial swirler includes a first radial passage separated from a second radial passage. The first radial passage has a first plurality of swirler vanes and the second radial passage has a second plurality of swirler vanes. The first radial passage is in fluid communication with the outer flow passage and the second radial passage is in fluid communication with the inner flow passage.