MULTI-STAGE CENTRIFUGAL COMPRESSOR AND RETURN CHANNELS THEREFOR

摘要

A multi-stage impeller is configured in a multi-stage centrifugal compressor (10) by fixing and attaching a plurality of centrifugal impellers (1a-1e) to one rotating shaft (8). Diffusers (2a-2e) and return channels (3a-3d) are provided in order downstream from each impeller. The centrifugal impellers, the diffusers and the return channels are housed within a compressor casing (6). The return channels have a plurality of vanes (3f-3i) positioned at intervals from one another in a circumferential direction, and at least two stages are provided. The vane exit angles (ß3f-ß3i) monotonically increase toward the downstream stage.