Multistage axial flow pumps and compressors
AssigneeWeir Pumps Limited
InventorMichael L. Ryall
Life of this patent
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Abstract
A multistage axial flow pump or compressor comprises at least one stage (10) including a rotor (16) and a stator (20). The rotor (16) is arranged to impart whirl in one direction, while the stator (20) is arranged to impart whirl in the opposite direction. This arrangement is useful in providing comparatively high stage pressures for a given rotor tip velocity with relatively low rotor vane hydraulic loadings. The arrangement is also useful in pumping multiphase fluids.
Claims25
An axial flow pump for use in pumping a multiphase fluid, the pump comprising at least one stage having a rotor for imparting whirl in one direction and two stators for imparting whirl in the opposite direction to maintain entrainment of the gas phase of the fluid within the liquid phase, one stator being upstream of the rotor and the other stator being downstream of the rotor.
A multistage axial flow pump or compressor comprising at least one stage including a rotor for imparting whirl in one direction and an inter-stage stator for imparting whirl in the opposite direction and having a plurality of vanes defining curved arcuate passages therebetween, the cross-sectional area of each passage being substantially constant along the whole length of the curved arc of each passage whereby the stator produces little or no diffusion.
A method of pumping or compressing a fluid utilizing a multistage axial pump or compressor, the method including the steps of:
- imparting whirl to the fluid in a first rotor;
- and then imparting whirl to the fluid in the opposite direction in a first stator with little or not diffusion such that, at or near the design duty flow, the fluid is discharged from the stator with an absolute velocity with has substantially the same axial component as the fluid entering the stator, and has a whirl component of velocity which is substantially the same as the whirl component entering the stator, but in the opposite rotational direction.
Dependencies are inferred from the claim text.