How does a radial-flow centrifugal pump differ from an axial-flow centrifugal pump?

In engineering, the primary difference between radial-flow and axial-flow centrifugal pumps lies in the direction of fluid movement relative to the pump's axis of rotation.1

Radial-Flow Pumps

Often referred to as straight centrifugal pumps, these units draw fluid in near the axis of a high-speed impeller. The fluid is then thrown radially outward into the casing. This design relies on centrifugal force to move the fluid, which is then directed through a volute or a ring of diffuser vanes to convert velocity head into pressure head.12

Axial-Flow Pumps

In axial-flow centrifugal pumps, the rotor functions as a propeller rather than a standard impeller. The fluid flows parallel to the axis of rotation throughout the process. Because the fluid maintains this parallel path, these pumps typically incorporate diffusion vanes in the discharge port to eliminate the rotational velocity imparted by the propeller.1

While radial-flow pumps are highly versatile for various liquid applications, axial-flow designs are specifically configured to handle fluid movement along the axis, making them distinct in their mechanical approach to pressure generation.13