What are the functions and principles of a centrifugal pump?

In a centrifugal pump, the impeller is fixed to the pump shaft; this impeller has several curved blades. The pump shaft rotates under the action of external forces, and the impeller rotates as well. The suction inlet located at the center of the pump casing is connected to the suction pipe, while the discharge outlet on the side is connected to the discharge pipeline. Before operation, the impeller inside the centrifugal pump is fixed to the pump shaft; the impeller has several curved blades. When the pump shaft rotates under external force, the impeller rotates as well. The suction inlet at the center of the pump casing is connected to the suction pipe, while the discharge outlet on the side is connected to the discharge pipeline 9. Before starting, it is necessary to fill the liquid, that is, to fill the shell with the liquid to be transported. After the motor is started, the pump shaft drives the impeller to rotate; the liquid filled between the blades rotates as well. Under the effect of inertial centrifugal force, the liquid is thrown from the center of the impeller toward its outer edge, gaining energy in the process. This increases the static pressure of the liquid at the outer edge of the impeller, as well as the flow velocity, which can generally reach 15–25 m/s. After the liquid leaves the impeller and enters the pump casing, as the flow channel in the casing gradually widens, the flow velocity of the liquid decreases, converting some of its kinetic energy into static pressure energy, which further increases the pressure of the liquid at the pump outlet. The liquid enters the discharge pipeline from the pump’s outlet at high pressure and is delivered to the desired location. As the liquid inside the pump is thrown from the center of the impeller to the outer edges, a low-pressure area is formed at the center. Since the pressure above the liquid surface in the reservoir is greater than the pressure at the pump’s suction inlet, this pressure difference causes the liquid to be continuously drawn into the pump through the suction pipeline, thereby replacing the liquid that has been discharged. As long as the impeller keeps rotating, liquid will continue to be drawn in and discharged. It can be seen that the reason why a centrifugal pump is able to transport liquids is mainly due to the high-speed rotating impeller; under the action of centrifugal force, the liquid gains energy, which increases its pressure. Air entrapment phenomenon: If no liquid is filled in, air remains inside the pump, and due to ρ_air

Thank you, it’s so comprehensive~! ~