Gas Dynamic Designs of Centrifugal Compressors for Gas Industry

Abstract

Centrifugal compressors for gas industry consume huge amount of energy. As a rule, they are single-shaft, with two or more stages and with comparatively low pressure ratio. Compressors operate at low Mach numbers and high Reynolds numbers. Two design parameters influence mostly stage performances. Stage flow coefficient optimal values lie in range 0.060–0.11. Chosen number of stages establishes value of this coefficient if speed of a rotor rotation is fixed. Design loading factor optimal values are 0.42–0.52. It corresponds to high efficiency, shifts a surge limit far from a design point and makes power maximal in a design point. Some considerations about impeller and diffuser types are presented. Design procedure consists on application of the Universal modeling programs for main dimensions optimization and performance calculations. Q3D non-viscid velocity diagrams are analyzed for optimization of blade configuration. Samples of design are presented, 32 MW single-stage pipeline compressor stage with record efficiency included.