The centrifugal pump is a hydraulic pump (turbomachine) that processes the working fluid in a constant volume over time through always open channels, with typically stationary flow (thus, no valves are needed inside).
When the impeller is rotated, it also imparts rotation to the fluid (kinetic energy) and a depression in the suction duct which, along with the thrust of atmospheric pressure, sucks the liquid into the centrifugal pump.
The fluid follows a trajectory from the center of the impeller to its periphery due to the action of centrifugal forces, and passes through the increasingly large channels formed by the curved blades. Already in this path, part of the kinetic energy is transformed into pressure energy.
Upon exiting the impeller, the fluid enters the volute, which also has an increasing section, and the remaining amount of kinetic energy is transformed into pressure energy, increasing the head. The more pressure energy transferred to the fluid, and therefore the head of the pump, the further the working fluid can be sent.
The operating range of the centrifugal pump is strictly limited to its characteristic curve.