Patent ID: 6540481
Filing Date: 2003-04-01
Classification: F01D,F04D,F05D,Y02T

Abstract:
A diffuser for a centrifugal compressor that includes an impeller rotatably carried within a casing, said diffuser comprising:a plurality of substantially linearly-extending diffuser passageways having respective longitudinal axes disposed tangentially to an imaginary circle having its center coincident with the impeller axis, the diffuser passageways including a diffuser inlet region commencing adjacent the impeller periphery, a diffuser throat region downstream of the diffuser inlet region, and a diffuser outlet region downstream of the diffuser throat region, wherein the diffuser passageways are each bounded by a pair of circumferentially spaced diffuser panels having respective leading edges adjacent the impeller periphery and that lie on a diffuser leading edge circle, and trailing edges spaced radially outwardly of and circumferentially offset from the leading edges and that lie on a diffuser trailing edge circle; and a pair of opposed ridges extending substantially longitudinally relative to and within the diffuser inlet region between the impeller periphery and the diffuser leading edge circle, each ridge varying in height along the diffuser inlet region and extending partially inwardly into the diffuser passageway, wherein the ridges are positioned between and are spaced from the leading edges of adjacent diffuser panels for mixing of air leaving the impeller and entering the diffuser passageway, to reduce boundary layer buildup within the diffuser passageway upstream of the diffuser throat region.