Which type of pump has an impeller rotating in a channel of constant cross-sectional area, imparting mixed or radial flow to the water?

The type of pump described is one where the impeller rotates within a channel that maintains a consistent cross-sectional area, which is characteristic of the vertical turbine pump. In a vertical turbine pump, the impeller moves the water radially outward, generating pressure that effectively lifts water from deep wells or reservoirs to the surface.

This configuration allows for efficient energy transfer from the impeller to the water, as the consistent channel width helps maintain flow velocity and pressure throughout the pumping process. Vertical turbine pumps are primarily used in applications requiring high flow rates, such as irrigation, municipal water systems, and industrial processes.

While axial-flow pumps are designed to create a flow of water in an axial direction (along the axis of the pump), centrifugal pumps utilize a rotating impeller to provide radial flow but do not necessarily function within a channel of constant cross-section in the same manner as vertical turbine pumps. Submersible pumps, on the other hand, are submerged in the fluid they are pumping but also do not specifically describe the impeller and channel characteristics present in the pump type indicated in the question.