Machine for moving fluid by spinning it using a rotating impeller in a casing with a central inlet and a tangential outlet. NOTE The path of the fluid is an increasing spiral from the inlet at the centre to the outlet, tangent to the impeller annulus. In the annular space between the impeller vane tips and the casing wall, the fluid velocity is roughly the same as that of the impeller vane tips. Useful work is produced by the pump when some of the spinning fluid flows out of the casing tangential outlet into the pipe system. Power from the motor is used to accelerate the fluid entering the inlet up to the speed of the fluid in the annulus. Some of the motor power is expended as friction of the fluid in the casing and impeller.
Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards
Rotating machine device that uses centrifugal force to convert mechanical energy into pressure or head.
Source: IADC UBO / MPD Glossary, December 2011. Global Standards