Reaction Turbines

In a reaction turbine, the runner utilizes both potential and kinetic energies. As flows through the stationary part of the turbine, the whole of its pressure energy is not transformed into kinetic energy and when the water flows through the moving parts, there is a change both in pressure and in the direction and velocity of flow of water. As the water gives up its energy to the runner, both its pressure and absolute velocity were reduced. The water, which acts on the runner blades is under a pressure above atmospheric and the runner passages are always completely filled with water.

The important reaction turbines are Francis and Kaplan which are discussed in this chapter according to their specification related to hydro–electric power plant. Theory for each type presented with sort notes and solved problems.

Keywords: Draft Tube, Flowrate through Reaction Turbine, Net Head, Reaction Turbine, Supply and discharge systems, Velocity Triangle.