CENTRIFUGAL IMPELLER, SINGLE-SHAFT MULTIPLE-STAGE CENTRIFUGAL COMPRESSOR USING CENTRIFUGAL IMPELLER, AND CENTRIFUGAL IMPELLER MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a centrifugal impeller and a single-shaft multistage centrifugal compressor having a wider operating range at low cost while ensuring high performance.SOLUTION: Blades of a centrifugal impeller according to the present invention are constituted by main blades each having a blade shape such that a blade load from a front edge thereof to a throat position is lighter than a blade load from the throat position to a rear edge thereof, and intermediate blades each having a front edge provided downstream of the throat position and shorter than the main blade. The main blades and the intermediate blades are alternately disposed circumferentially between an impeller hub and a shroud facing the impeller hub, the main blades are integrally joined to the impeller hub and the shroud, and the intermediate blades are integrally joined to at least either the impeller hub or the shroud. Furthermore, a single-shaft multistage compressor according to the present invention is configured so that the centrifugal impeller is disposed in at least a most downstream stage.SELECTED DRAWING: Figure 2