The dimensionless characteristics of centrifugal compressor stage axial-radial impeller
UDC 621.515
V.A. Korotkov, Tatarenko U.V.
Abstract
The improvement of compressor design is one of the major trends in the refrigerating engineering nowadays, developing parts of centrifugal compressor flow channel to improve their efficiency being one of them. The articles deals with the experimental results of the halocarbon compressor end stage with single shrouded axial-radial impeller. The outlet angle of the compressor impeller vanes is 90о. The profile shape of the impeller interblade channel is adjusted to minimize flow channel in relative motion. Vaned diffuser with the wing shaped blades is also analyzed as part of the compressor end stage. The angle of incidence of the blade is from 5о to 23о. The dimensionless characteristics of the impeller in question (loss factor, power factor, reactivity coefficient) are shown. They allow us to draw a conclusion on performance gain for the impeller but for a particular range of discharge coefficient only. The changes in Mach number of the peripheral velocity don’t make a significant impact on these factors. When the angles of incidence of the diffuser blades are small one should imply forced whirl at the impeller inlet in the direction of rotation. Whirl at the impeller inlet doesn’t affect the loss factor of the stage output element.
Keywords: analysis, centrifugal compressor stage, impeller, diffuser, characteristics.
The dimensionless characteristics of centrifugal compressor stage axial-radial impeller
Abstract
The improvement of compressor design is one of the major trends in the refrigerating engineering nowadays, developing parts of centrifugal compressor flow channel to improve their efficiency being one of them. The articles deals with the experimental results of the halocarbon compressor end stage with single shrouded axial-radial impeller. The outlet angle of the compressor impeller vanes is 90о. The profile shape of the impeller interblade channel is adjusted to minimize flow channel in relative motion. Vaned diffuser with the wing shaped blades is also analyzed as part of the compressor end stage. The angle of incidence of the blade is from 5о to 23о. The dimensionless characteristics of the impeller in question (loss factor, power factor, reactivity coefficient) are shown. They allow us to draw a conclusion on performance gain for the impeller but for a particular range of discharge coefficient only. The changes in Mach number of the peripheral velocity don’t make a significant impact on these factors. When the angles of incidence of the diffuser blades are small one should imply forced whirl at the impeller inlet in the direction of rotation. Whirl at the impeller inlet doesn’t affect the loss factor of the stage output element.
Keywords: analysis, centrifugal compressor stage, impeller, diffuser, characteristics.