Inducer for a submersible pump for pumping a slurry containing solids and viscous fluids and method of designing same

An inducer for a submersible slurry pump configured to pump a slurry containing solids and viscous fluids, the pump including an impeller having an impeller blade height and a plurality of impeller blades, the solids having a maximum diameter equal to the impeller blade height of the pump, the inducer configured to be positioned within a casing of the pump and mountable to a drive shaft of the pump so as to be adjacent to and immediately upstream of the impeller mounted on the drive shaft, wherein the inducer and impeller are rotated on the drive shaft in a direction of rotation, the inducer comprising:

• a hub,
• at least two and no more than four inducer blades mounted to and extending axially along the hub, the inducer blades extending outwardly from and wrapping helically around the hub, the hub and the inducer blades thereby defining a plurality of continuous channels, each channel of the plurality of continuous channels bounded by the hub, the inducer blades, the plurality of impeller blades and an inner surface of the casing,
• wherein a trailing edge of each blade of the inducer blades is configured to be positioned adjacent to and aligned with a leading edge of each corresponding blade of the plurality of impeller blades of the impeller when the inducer is mounted on the drive shaft of the pump and a horizontal plane passing through an axial surface of the leading edge of each corresponding blade of the plurality of the impeller blades intersects the inducer blades, such that a curve representing a velocity of the slurry is substantially smooth as the slurry travels through the plurality of continuous channels from a leading edge of each blade of the inducer blades to the leading edge of each impeller blade of the plurality of impeller blades.