Core exhaust mixer, having a variable area, for turbo-fan jet engines of supersonic aircraft

Core exhaust mixer, having a variable area, for turbo-fan jet engines of supersonic aircraft, comprising a substantially cylindrical nozzle (24) centered on a longitudinal axis (X-X) of the jet engine (2) and intended to be arranged concentrically about a gas generator (4) of the jet engine, the nozzle (24) comprising a plurality of external air intake apertures (30) distributed over its entire circumference, emerging in a convergence zone (22) between the cold and hot flows from the gas generator (4) and in which lobes (32), movable between two positions, are mounted;

• a first position in which they block the apertures (30) of the nozzle (24) and a second position, different from the first, in which they unblock said apertures (30) and extend radially into the nozzle (24) in order to admit air, external to the jet engine, into said convergence zone (22), characterized in that the lobes (32) have an azimuthal component in the same direction, in order to give a swirling motion to the external air admitted into the convergence zone when the lobes are in the second position.