CENTRIFUGAL COMPRESSOR USING AN ASYMMETRIC SELF-RECIRCULATING CASING TREATMENT

摘要

In the provided centrifugal compressor, a back-flow path (9) is formed inside a casing (7). Said back-flow path returns a fluid from downstream of the leading edge of all blades of an impeller (6a) to upstream of said leading edge (6a). The back-flow path (9) has: a suction ring groove (9a) that extends in the circumferential direction and opens to a downstream part of the inside surface (7a) of the casing (7); and a back-flow ring groove (9b) that extends in the circumferential direction and opens to an upstream part of said inside surface (7a). The circumferential variation in the axial position or width of the suction ring groove (9a) is asymmetric with respect to an axis of rotation.