Patent ID: 7827798

Claim:
A system for ventilating a combustion chamber wall in a turbomachine comprising: a centrifugal compressor; a diffuser; the combustion chamber including a radially external wall and a radially internal wall; an internal casing with a substantially L-shaped section that is connected to the diffuser and that extends downstream to air injection means for ventilating a turbine; and an annular convecting metal sheet arranged radially between the combustion chamber and the internal casing and extends axially from the diffuser to the air injection means along the radially internal wall of the combustion chamber in order to delimit, with the radially internal wall of the combustion chamber, an annular stream for the flow of air without separation and with reduced pressure losses, intended to supply holes in the internal wall of the combustion chamber and the air injection means, wherein the metal sheet includes a cylindrical upstream portion, a frustoconical intermediate portion, and a radial downstream portion, wherein a first end of the cylindrical upstream portion is attached to the diffuser, a second end of the cylindrical upstream portion is connected to the frustoconical intermediate portion, and the cylindrical upstream portion between the first end and the second end is parallel to an axis of the turbomachine, and wherein the intermediate portion is substantially parallel to the radially internal wall of the combustion chamber.