Patent ID: 9003805
Filing Date: 2015-04-14
Classification: F01D,F02C,F04D,F05D,Y02T

Abstract:
1. A turbomachine comprising: an annular combustion chamber; a centrifugal compressor; an annular diffuser serving to diffuse the gas stream leaving the compressor and to direct the gas stream towards the combustion chamber, the diffuser comprising: a radially oriented upstream portion presenting diffusion passages connected to an outlet of the compressor; a curved intermediate portion; and a downstream portion having a series of circularly spaced-apart deflector vanes; and an outer casing externally surrounding the combustion chamber and the downstream portion, wherein an inside wall of the upstream portion, the intermediate portion, and the downstream portion are continuously defined by a first cheekplate, an outer wall of the upstream portion and the intermediate portion are continuously defined by a second cheekplate, and the first and second cheekplates define a flow passage in the upstream and intermediate portions and are separate from the outer casing, wherein a portion of the outer casing near an upstream end thereof presents a radial shoulder which axially abuts against a downstream end of the second cheekplate defining the outer wall of the intermediate portion, wherein a zone of the outer casing that is situated facing the deflector vanes of the downstream portion is covered by a coating of abradable material, wherein an outside of a flow passage through the downstream portion is defined by the outer casing and by said coating and an inside of the flow passage through the downstream portion is defined by the first cheekplate, and wherein the downstream end of the second cheekplate presents a cylindrical surface which abuts against an inner cylindrical surface of the portion of the outer casing, the inner cylindrical surface being radially offset from the zone of the outer casing covered by the coating by at least a radial dimension of the shoulder.