Patent ID: 6151899
Filing Date: 2000-11-28
Classification: F23C,F23D,F23R

Abstract:
A lean-burn combustor for a gas-turbine engine, the combustor having, in flow series, a radial inflow premixing burner, an axial flow combustion pre-chamber having a cross-sectional area and an axial centerline, and an axial flow main combustion chamber having a larger cross-sectional area than the pre-chamber, the burner comprising:a) a fuel and air mixing device located radially outwardly of the pre-chamber for mixing primary fuel and air before a resulting fuel and air mixture enters the pre-chamber, the mixing device being adapted to impose on the fuel and air mixture entering the pre-chamber a motion having a vigorous swirling component about the axial centerline of the pre-chamber;b) a burner face located radially inwardly of the fuel and air mixing device and forming an axially upstream wall of the pre-chamber, the burner face incorporating pilot fuel injection means for injection of pilot fuel into the pre-chamber;c) whereby, during operation of the combustor, an axial re-circulating vortex core flow of gases extends between the burner face and an upstream part of the main chamber; andd) the pilot fuel injection means being disposed within a recess in the burner face, the recess being substantially circular in plan view, the pilot fuel injection means being adapted to inject the pilot fuel into the recess in a substantially tangential direction with respect to the circular recess, whereby operating temperatures of the burner face are thereby reduced and combustion characteristics improved.