Gas turbine engine with means for reducing the formation and emission of nitrogen oxides

Claim 2

In a gas turbine engine having a compressor, combustor and turbine in serial flow relation, means for reducing the formation of oxides of nitrogen within the combustor comprise: means within said combustor defining a primary combustion zone, a secondary combustion zone, and a dilution zone; means for bleeding a portion of the airflow pressurized by the compressor; means for cooling the airflow bled from the compressor; means for directing the unbled portion of compressor discharge airflow to the primary combustion, secondary combustion, and dilution zones of the combustor in order to support combustion in the primary combustion zone; and means for introducing the cooled compressor bleed airflow into the primary combustion zone of the combustion in order to reduce the flame temperature.

Claim 3

In a gas turbine engine of the bypass front fan type having a core compressor, combustor and turbine in serial flow relation, means for reducing the formation of oxides of nitrogen within the combustor comprise: means within said combustor defining a primary combustion zone, a secondary combustion zone, and a dilution zone; means for bleeding a portion of the airflow pressurized by the compressor; means for directing the airflow bled from the compressor into heat exchange relation with the bypass airflow in order to cool the compressor bleed airflow; means for directing the unbled portion of compressor discharge airflow to the primary combustion, secondary combustion, and dilution zones of the combustor in order to support combustion in the primary combustion zone, and means for introducing the cooled compressor bleed airflow into the primary combustion zone of the combustor in order to reduce the flame temperature.

Claim 4

In a gas turbine engine of the bypass front fan type having a core compressor, combustor and turbine in serial flow relation, means for reducing the formation of oxides of nitrogen within the combustor comprise: means within said combustor defining a primary combustion zone, a secondary combustion zone, and a dilution zone; means for bleeding a portion of the airflow pressurized by the compressor; means for directing the airflow bled from the compressor into heat exchange relation with the bypass airflow in order to cool the compressor bleed airflow; means for directing the unbled portion of compressor discharge airflow to the primary combustion, secondary combustion, and dilution zones of the combustor in order to support combustion in the primary combustion zone, and means for introducing the cooled compressor bleed airflow into the primary combustion zone of the combustor in order to reduce the flame temperature.

Claim 5

The gas turbine engine of claim 2 wherein the means for directing the compressor bleed airflow into heat exchange relation with the bypass airflow includes a heat exchanger having at least two passages arranged in heat exchange relationship wherein one of the passages receives and discharges bypass airflow and the other passage receives and discharges compressor bleed airflow.

Claim 6

The gas turbine engine of claim 2 wherein the means for reintroducing the cooled compressor bleed airflow back into the primary zone of the combustor includes: a spin chamber in general surrounding relation to a fuel injection apparatus wherein the spin chamber receives the cooled compressor bleed airflow and directs the airflow in a circular motion of ever decreasing radius so as to generate a vortical flow around the fuel injection apparatus, and, conduit means communicating from the spin chamber to the heat exchange means for directing the cooled compressor bleed airflow therebetween.

Claim 7

The gas turbine engine of claim 4 wherein the spin chamber includes: an involute outer wall and generally planar spaced upstream and downstream annular end walls, the outside edges of which are peripherally joined to the outer wall and the inside edges of which define an annular outlet which surrounds the fuel injection apparatus; a plurality of circumferentially spaced apart swirl vanes extending between the upstream and downstream end walls in spaced apart relation to the outer wall; and an inlet in direct communication with the conduit means for receipt of the cooled compressor bleed airflow.