Turbomachine nozzle cover provided with triangular patterns having a point of inflexion for reducing jet noise

1. An annular cover for a turbomachine nozzle, the cover having a plurality of patterns extending a trailing edge of said cover and spaced apart circumferentially from one another, each pattern having an outline that is substantially triangular in shape, with a base formed by a portion of the trailing edge of the cover and a vertex spaced downstream from the base and connected thereto by two sides, wherein, for each pattern:

the vertex presents an outline that is substantially curved;

each side is connected to the trailing edge of the cover following an outline that is substantially curved having a radius of curvature that is greater than the radius of curvature of the outline of the vertex; and

the outline of each of the sides includes at least one point of inflexion having a tangent that is substantially parallel to the base.

2. A cover according to claim 1 , in which the vertex of at least one of the patterns is inclined radially towards the inside of the cover.

3. A cover according to claim 1 , in which each pattern is situated entirely in a single plane.

4. A cover according to claim 1 , in which the points of inflexion of each pattern are situated in a zone lying in the range 40% to 60% of the height of said pattern.

5. A cover according to claim 1 , in which at least one of the patterns presents symmetry about a plane containing the axis of symmetry of the cover and the vertex of said pattern.

6. A turbomachine nozzle including a primary cover disposed about a longitudinal axis of the nozzle and a secondary cover disposed coaxially about the primary cover, wherein the primary cover and/or the secondary cover is/are a cover according to claim 1 .

7. A turbomachine including a nozzle having at least one cover according to claim 1 .