Reaction Turbine and Impulse Turbine

The reaction turbine is quite different from the impulse turbine.

In the reaction turbine a portion of the energy of the fluid is converted into energy by the fluid’s passing through adjustable gates before entering the runner, and the remainder of the conversion takes place through the runner.

Two types of the reaction turbines:
-Radial flow, e.g Francis turbine
-Axial flow, e.g Kaplan turbine

In the impulse turbine all the mechanical energy of the liquid is converted into kinetic energy by a nozzle that forms a free jet. The energy is then taken from the jet by suitable flow through moving vanes.The vanes are partly filled with the jet open to the atmosphere throughout its travel through the runner.

Type of the impulse turbine, e.g Pelton Wheel