What is a key feature of rotary pumps?

Rotary pumps are defined by their mechanism of fluid movement, which involves the use of rotating elements. This characteristic allows them to efficiently transfer fluids by trapping a specific volume of fluid and moving it through the pump. The rotating components create a continuous flow by maintaining a consistent motion, which is particularly effective for a wide range of fluids, including both viscous and low-viscosity liquids. This design contributes to their ability to produce a steady flow rate and pressure, making them suitable for many applications in various industries.

The other choices do not accurately reflect the fundamental attributes of rotary pumps. While they can handle viscous fluids, it is not an exclusive feature. The generation of flow is not primarily through pressure reduction, as may be the case with other pump types like centrifugal pumps. Additionally, comparing rotary pumps to reciprocating pumps in terms of speed does not define their essential functionality. The focus is on their unique use of rotating elements, confirming why this aspect stands out as a key feature of rotary pumps.