Turbines are the modern version of Water Wheels which are used to generate electricity in Hydro Electric Power Plant. Working on many considerations, Engineers had developed different types of Turbines. In this article I will share my knowledge on Impulse Turbine.
As the name indicates, An Impulse Turbine is a turbine which runs by the impulse of water. In an impulse turbine, the water from dam is made to flow through the pipeline, and then through guide mechanism and finally through the nozzles. In this transportation process of water from dam to turbine, the entire available energy of the water is converted into Kinetic Energy by passing through nozzles. These nozzles are kept as much as closer to the runner. The water enters the running wheel in the form of Jets, which impinges on the buckets, fixed on the outer periphery of the wheel.
The energy to the runner is imparted by the jet of water impinges on the buckets with high velocity. The pressure of water at entering and leaving the vanes is atmospheric.
Different Efficiencies of Impulse Turbine
To measure the efficiency of Impulse Turbine, we can use following three types of efficiencies. Basically efficiency is the ratio of work done by the turbine to the energy supplied.
01) Hydraulic Efficiency
It is the ratio of work done on the wheel to the energy of the jet.
02) Mechanical Efficiency
In practical, it is observed that all the energy supplied to the wheel does not come out as the useful work. To overcome the friction of bearing and other moving parts some of the energy is wasted. Keeping this point in mind, the mechanical efficiency is the ratio of actual work available at the turbine to the energy imparted to the wheel.
03) Overall Efficiency
It is the ratio of actual power produced by the turbine to the energy actually supplied by the turbine. With this efficiency we can measure the performance of the turbine.
Some other useful articles…