US Patent 10935245 Annular concentric fuel nozzle assembly with annular depression and radial inlet ports

A fuel nozzle for a gas turbine engine is generally provided. The fuel nozzle includes an outer sleeve extended circumferentially around a fuel nozzle centerline and extended along a longitudinal direction substantially co-directional to the fuel nozzle centerline. The outer sleeve defines a plurality of first radially oriented air inlet ports through the outer sleeve in circumferential arrangement relative to the fuel nozzle centerline. The fuel nozzle further includes a centerbody positioned radially inward of the outer sleeve. The centerbody is extended along the longitudinal direction substantially co-directional to the fuel nozzle centerline and wherein the centerbody is concentric to the fuel nozzle centerline and the outer sleeve. The centerbody defines a plurality of second radially oriented air inlet ports through the centerbody in circumferential arrangement relative to the fuel nozzle centerline. The centerbody further defines an annular centerbody groove or depression relative to the fuel nozzle centerline at a downstream end directly adjacent to a combustion chamber. The fuel nozzle further includes an inner sleeve extended circumferentially around the fuel nozzle centerline and extended along the longitudinal direction substantially co-directional to the fuel nozzle centerline. The inner sleeve is positioned radially between the outer sleeve and the centerbody. The inner sleeve further defines an annular inner sleeve depression relative to the fuel nozzle centerline at the downstream end directly adjacent to the combustion chamber. The outer sleeve and the inner sleeve together define a first fuel air mixing passage radially therebetween and extended substantially along the longitudinal direction in direct fluid communication with the combustion chamber. The inner sleeve and the centerbody together further define a second fuel air mixing passage radially therebetween and extended substantially along the longitudinal direction in direct fluid communication with the combustion chamber.