Both positive displacement pumps and non-positive displacement pumps belong to hydraulic pumps, and non-positive displacement pumps are pumps that increase the liquid potential energy by increasing the kinetic energy of the liquid.
Non-positive displacement types include centrifugal pumps, axial flow pumps, etc., which use a high-speed rotating impeller to generate a vacuum at the inlet to suck in liquid, and continuously output pressure liquid at the outlet. The inlet of this pump is connected to the outlet, the efficiency decreases with the increase of the liquid viscosity, and the output liquid volume decreases significantly with the increase of the outlet pressure.
