A fuel-air mixer, comprising: an annular shroud having a circular cross section defined by a wall, the annular shroud having an axial axis extending along an axial direction, a radial axis extending along a radial direction, and upstream and downstream end portions; a first swirler disposed at the upstream end portion of the annular shroud; a second swirler disposed at the upstream end portion of the annular shroud outwardly from the first swirler in the radial direction; a hub separating the first and second swirlers, the hub being configured to allow independent rotation of first and a second portions of a first gas stream entering the annular shroud at the upstream end portion thereof, the first and second portions of the first gas stream being rotated by the first and second swirlers, respectively; a center body extending along the axial axis of the annular shroud; a fuel shroud disposed at the upstream end portion of the annular shroud outwardly from the second swirler in the radial direction and circumferentially around the annular shroud, the fuel shroud being configured to inject a fuel into the annular shroud to be mixed with the first and second portions of the first gas stream and a second gas stream upstream of a combustion chamber, the second gas stream being a stream of air; a third radial swirler disposed downstream of the first and second swirlers (80, 82), wherein the third radial swirler is configured to introduce the second gas stream entering the annular shroud at a region adjacent the wall of the annular shroud and being configured to allow an independent rotation of the second gas stream so as to reduce a local fuel concentration at an exit of the annular shroud in a region adjacent the wall of the annular shroud, characterized in the third swirler comprising a first ring having a plurality of vanes disposed on an outer surface thereof and an annular lip extending axially from an inner edge of the first ring and a second ring disposed axially away from the first ring so as to form a gap therebetween containing the plurality of vanes disposed on the outer surface of the first ring, the second ring including a first surface extending radially inward so as to form a first portion of the gap and a second surface extending axially so as to form a second portion of the gap, the second ring also including a sleeve configured to receive the annular shroud of the fuel-air mixer. an annular shroud having a circular cross section defined by a wall, the annular shroud having an axial axis extending along an axial direction, a radial axis extending along a radial direction, and upstream and downstream end portions; a first swirler disposed at the upstream end portion of the annular shroud; a second swirler disposed at the upstream end portion of the annular shroud outwardly from the first swirler in the radial direction; a hub separating the first and second swirlers, the hub being configured to allow independent rotation of first and a second portions of a first gas stream entering the annular shroud at the upstream end portion thereof, the first and second portions of the first gas stream being rotated by the first and second swirlers, respectively; a center body extending along the axial axis of the annular shroud; a fuel shroud disposed at the upstream end portion of the annular shroud outwardly from the second swirler in the radial direction and circumferentially around the annular shroud, the fuel shroud being configured to inject a fuel into the annular shroud to be mixed with the first and second portions of the first gas stream and a second gas stream upstream of a combustion chamber, the second gas stream being a stream of air; a third radial swirler disposed downstream of the first and second swirlers (80, 82), wherein the third radial swirler is configured to introduce the second gas stream entering the annular shroud at a region adjacent the wall of the annular shroud and being configured to allow an independent rotation of the second gas stream so as to reduce a local fuel concentration at an exit of the annular shroud in a region adjacent the wall of the annular shroud, characterized in the third swirler comprising a first ring having a plurality of vanes disposed on an outer surface thereof and an annular lip extending axially from an inner edge of the first ring and a second ring disposed axially away from the first ring so as to form a gap therebetween containing the plurality of vanes disposed on the outer surface of the first ring, the second ring including a first surface extending radially inward so as to form a first portion of the gap and a second surface extending axially so as to form a second portion of the gap, the second ring also including a sleeve configured to receive the annular shroud of the fuel-air mixer.