Electric submersible pump and other centrifugal pump stages having non-axisymmetric components and passage contours are disclosed. Such a component can be a shrouded impeller having a non-axisymmetric profile for its hub and/or shroud.

A submersible pump assembly. The submersible pump assembly comprises a motor comprising a first drive shaft; a seal section comprising a second drive shaft that is coupled to the first drive shaft of the motor; and a centrifugal pump assembly comprising a third drive shaft that is coupled to the second drive shaft of the seal section and a plurality of pump stages, wherein each pump stage comprises an impeller coupled to the third drive shaft and a diffuser retained by a housing of the centrifugal pump assembly, wherein the diffuser of each pump stage comprises a first plurality of vanes each having a first axial length and a second plurality of vanes each disposed between a pair of vanes of the first plurality of vanes and each having a second axial length, wherein the second axial length is less than the first axial length.

A submersible pump assembly. The submersible pump assembly comprises a motor comprising a first drive shaft; a seal section comprising a second drive shaft that is coupled to the first drive shaft of the motor; and a centrifugal pump assembly comprising a third drive shaft that is coupled to the second drive shaft of the seal section and a plurality of pump stages, wherein each pump stage comprises an impeller coupled to the third drive shaft and a diffuser retained by a housing of the centrifugal pump assembly, wherein the diffuser of each pump stage comprises a first plurality of vanes each having a first axial length and a second plurality of vanes each disposed between a pair of vanes of the first plurality of vanes and each having a second axial length, wherein the second axial length is less than the first axial length.

A water supply system (1) includes an electric motor (8) and a centrifugal pump (7) which is driven by the electric motor (8) and with at least one impeller (10) which produces a main delivery flow (29) through an annular space (12) as well as a cooling fluid delivery flow (30) through a space (28) surrounding the motor (8). The annular space (12) is divided by two guide vanes into part-annular-spaces (23, 24) which have a different pressure level on operation. Each part-annular-space (23, 24) is conductively connected to the space (28) which surrounds the motor (8) and through which the cooling fluid runs (FIG. 5).

A multistage centrifugal grinder pump includes a grinder to grind a fluid, a first stage impeller, a second stage impeller, a stationary diffusor arranged between the first stage impeller and the second stage impeller to guide the fluid from the first stage impeller to the second stage impeller and a shaft to rotate the first stage impeller, the second stage impeller and the grinder. The first and second stage impellers in series and connected to the shaft in a torque-proof manner. The diffusor is a semi-open diffusor having a top wall, a radially outer annular side wall, and an open bottom side facing the first stage impeller, the top wall arranged adjacent the second stage impeller, the top wall having a central outlet opening surrounding the shaft, and the open bottom side extending beyond the first stage impeller with respect to a radial direction.

A fluid pump assembly is provided. The pump has a pair of units magnetically coupled to each other. The first unit contains a drive motor and a magnetic assembly. The second unit contains a magnetic assembly and a blade of a propeller/impeller for imparting movement to a fluid. As the first unit is activated by the drive motor, a magnetic flux is created which in turn rotates the magnetic assembly in the second unit, driving the blade.

A pump assembly for a dishwashing appliance includes an inner diffuser shell defining a motor housing and an outer diffuser shell spaced apart from the inner diffuser shell to define a diffusing plenum. A motor positioned within the motor housing rotates a wash pump impeller and urges a flow of wash fluid through the diffusing plenum. Within the diffusing plenum, guide vanes extend between the inner diffuser shell and the outer diffuser shell to diffuse and direct the flow of wash fluid.

A pump assembly for a dishwashing appliance includes an inner diffuser shell defining a motor housing and an outer diffuser shell spaced apart from the inner diffuser shell to define a diffusing plenum. A motor positioned within the motor housing rotates a wash pump impeller and urges a flow of wash fluid through the diffusing plenum. Within the diffusing plenum, guide vanes extend between the inner diffuser shell and the outer diffuser shell to diffuse and direct the flow of wash fluid. The motor is powered by electrical wires that pass through a hole defined through the outer diffuser shell, through one of the plurality of guide vanes, and through the inner diffuser shell.

An impeller includes a disk, a long blade that is disposed at an interval in a circumferential direction on a disk surface on a first side in an axial direction of the disk, and that reaches an outer peripheral edge of the disk, and a short blade that is disposed between the long blades adjacent to each other on the disk surface, and that reaches the outer peripheral edge. A circumferential length of the short blade gradually increases as the short blade faces outward in the radial direction, and a circumferential length of the long blade in the outer peripheral edge is smaller than the circumferential length of the short blade in the outer peripheral edge.

The present invention is a reversible pump-turbine installation position in a vertical shaft instead of in a conventional underground powerhouse or deep concrete powerhouse. The required plant cavitation coefficient may be achieved by simply boring a vertical shaft to the required depth rather than routing the water flow to and from a deeply buried powerhouse. A pneumatically controlled pressure relief valve may be incorporated into this invention.