초록 ▼

An exhaust mixer for a turbofan aeroengine can be classified as being of the multi-lobed type, with troughs between the lobes. Good mixing efficiency together with good aerodynamics, short axial length and low weight is achieved by forming the mixer from flow surfaces which are longitudinally twiste

An exhaust mixer for a turbofan aeroengine can be classified as being of the multi-lobed type, with troughs between the lobes. Good mixing efficiency together with good aerodynamics, short axial length and low weight is achieved by forming the mixer from flow surfaces which are longitudinally twisted between their upstream and downstream ends, opposing sides of each lobe and trough being of opposite twist. Between the upstream and downstream ends of the twisted flow surfaces, their latitudinal contours become approximately S-shaped so as to define outer portions of the lobes, inner portions of the troughs and the opposed sides of the lobes and troughs.

대표청구항 ▼

For a turbofan aeroengine, an exhaust mixer of the type comprising a plurality of lobes, through which portions of a turbine exhaust stream pass, and a plurality of troughs defined between said lobes, through which troughs portions of a fan air stream pass, said lobes and said troughs being at least

For a turbofan aeroengine, an exhaust mixer of the type comprising a plurality of lobes, through which portions of a turbine exhaust stream pass, and a plurality of troughs defined between said lobes, through which troughs portions of a fan air stream pass, said lobes and said troughs being at least partially defined by turbine exhaust stream contacting flow surfaces and fan air stream contacting flow surfaces respectively whereby each said lobe and each said trough has generally opposed sides extending longitudinally of said turbine exhaust and fan air streams, one such side of each of said lobes and troughs comprising a flow surface portion having a longitudinal clockwise progressive twist between its upstream and downstream ends and the other such side of each of said lobes and troughs comprising a flow surface portion having a similar but anticlockwise twist, said flow surfaces being shaped such that latitudinal contours of said flow surfaces at a succession of stations downstream of their upstream ends are sinuous shapes each with a single inflexion, said sinuous latitudinal contours having outwardly convex portions which at least partly delineate outer portions of said lobes, inwardly concave portions which at least partly delineate inner portions of said troughs, and intermediate portions between said outwardly convex and inwardly concave portions, which intermediate portions at least partially delineate said opposed sides of said lobes and troughs.