Working Principle of Pelton Turbines

Abstract

In hydropower plants with Pelton turbines, the available hydraulic energy exists as potential energy, which is measured in the form of the geodetic height difference between the upper level of water in the reservoir and the turbines in the machine house of a lower altitude. This height difference is denoted as hydraulic head in the terminology of hydropower. The conversion of the potential energy into the usable mechanical energy is completed by first converting the potential energy into kinetic energy in the form of high-speed jets at the altitude of the turbine wheel. For the energy conversion, one or many injectors can be used. By neglecting the friction losses in the injector, the jet speed is calculated according to the Bernoulli equation by

$$ {C}_0=\sqrt{2gH}, $$

with H as the net pressure head at the inlet of the injector. This equation is generally called the Torricelli formula.