Patent ID: 8104260

Claim:
An exhaust mixer for a gas turbine engine of the type having an annular bypass passage for channelling air from a fan flow and a main gas path passage, the exhaust mixer being adapted to receive a flow from the main gas path passage having a swirl component in a given direction, the exhaust mixer comprising an upstream end, a downstream end, and an annular wall extending therebetween and defining a plurality of circumferentially distributed alternating inner and outer lobes, the outer lobes protruding into the annular bypass passage and the inner lobes protruding into the main gas path passage, each of the inner lobes having a base defined in alignment with the upstream end of the mixer and a tip, each of the inner lobes being configured with a circumferential offset between sections of the base and tip thereof located at a same distance from the upstream end of the mixer, the circumferential offset progressively increasing as the distance from the upstream end of the mixer increases, a direction of the circumferential offset defined from the base to the tip of each of the inner lobes being the same for all of the inner lobes and opposite to that of the swirl component.