Patent ID: 6708711
Filing Date: 2004-03-23
Classification: B64D,F02C,Y10T

Abstract:
Air inlet for the nacelle of a commercial aircraft jet engine, said air inlet having its axis (Mâ€”M) coincident with that of said engine and exhibiting the form of an annular lip which comprises:an external annular aerodynamic surface for linking up with the external surface of said nacelle; an internal annular aerodynamic surface for linking up with the internal surface of said nacelle and channeling the air to said engine, said internal annular aerodynamic surface comprising an annular throat and forming at least in part a diffuser for the said engine; and a plane annular leading edge formed at the link-up of said external and internal annular aerodynamic surfaces, so that any section of said annular lip through a diametral plane comprises an external profile, an internal profile, a throat and a leading edge corresponding respectively to the traces, in said diametral plane, of said external and internal annular aerodynamic surfaces, of the annular throat and of said annular leading edge, said air inlet being symmetric with respect to its vertical diametral plane (Vâ€”V) and being of the chamfered type with the lower part of said lip forward with respect to the upper part of the latter and said annular leading edge inclined with respect to said axis (Mâ€”M), the inclination of said annular leading edge being defined, in the said vertical diametral plane (Vâ€”V), by the scarf angle Sc between the trace of the plane of said leading edge and the direction (8) perpendicular to said axis, wherein: with respect to the two horizontal sections (Sb) of said lip, the internal profile (5S(&thgr;)) of the upper sections (S(&thgr;)) of said lip comprises an internal bulge in the direction of said axis, said internal bulge extending on either side of the throat of said horizontal sections (Sb); the larger said scarf angle Sc, the bigger the internal bulge; and said internal bulge is a maximum at the upper vertical section S(0) of the said lip and decreases, progressively and symmetrically, toward said horizontal sections (Sb), where it disappears.