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Impeller
Rotor used to increase (or decrease in case of turbines) the pressure and flow of a fluid or gas / From Wikipedia, the free encyclopedia
An impeller, or impellor,[1] is a driven rotor used to increase the pressure and flow of a fluid. It is the opposite of a turbine, which extracts energy from, and reduces the pressure of, a flowing fluid.
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Strictly speaking, propellers are a sub-class of impellers where the flow both enters and leaves axially, but in many contexts the term "impeller" is reserved for non-propeller rotors where the flow enters axially and leaves radially, especially when creating suction in a pump or compressor.