A rotary pump is classified as which type of pump?

A rotary pump is classified as a positive displacement pump because it operates by trapping a fixed volume of fluid and then forcing it out into the discharge pipe. This action occurs through the rotating motion of internal components, such as gears, vanes, or lobes, which create a vacuum that draws in the fluid and subsequently displaces it.

Positive displacement pumps are known for their ability to move fluids at consistent flow rates regardless of the pressure within the system, making them ideal for applications that require precise fluid delivery. This is a crucial characteristic, as it allows for effective control and reliability in various refrigeration and industrial processes ensuring efficient operation.

In contrast, dynamic pumps, such as centrifugal pumps, primarily use kinetic energy to move the fluid and their flow rate can vary significantly with changes in pressure. Unlike rotary pumps that maintain a fixed displacement per cycle, these pumps rely on velocity to function, which differentiates their mode of operation fundamentally from that of positive displacement pumps.