What does the impeller of a centrifugal pump do?

The impeller of a centrifugal pump is designed to draw liquid into its center, which is a fundamental aspect of how the pump operates. Centrifugal pumps work by using rotational energy generated by the impeller to increase the velocity of the fluid. As the impeller spins, it creates a low-pressure area at its center that draws liquid from the surrounding area into the pump.

From the center of the impeller, the accelerated liquid is then pushed outward toward the pump casing, converting the velocity of the fluid into pressure that facilitates movement through the system. This design is crucial for effective pumping, as it allows fluids to be moved efficiently, aligning with the fundamental principles of fluid dynamics that underpin centrifugal pump technology.

The other options misunderstand the role of the impeller: while it does create high pressure as the liquid is expelled, it does not create a vacuum in a traditional sense for the purpose of pulling liquid. Instead, the liquid movement is primarily due to the kinetic energy imparted by the impeller's rotation. It also does not transmit pressure directly to the motor, and the drawing of liquid from the outer edge is not its primary function; rather, the flow enters through the inlet, moving toward the impeller's center before being pushed outwards