Introduction
This is a variant of Pelton Wheel turbine. Turgo turbine was developed in 1919’s by Gilkes Energy Company. Before getting into the details, let us first start with the definition of turgo turbine.
Turgo Turbine Meaning
Turgo turbine is an impulsive water turbine that handles flow rates more than the flow rates of Pelton turbine handles. The main difference between a Pelton turbine and a Turgo turbine is that Turgo turbines use single cups instead of double cups on the wheel, and these cups are more shallow. It has slightly less coefficient as compared to other turbines. Since the runners on these turbines are smaller and spin faster, some Turgo turbines can be connected directly to a generator instead of using a speed-increasing transmission.
Parts of Turgo Turbine
The components of the Turgo Turbine are similar to the Pelton wheel turbine. The components of Turgo turbine are as follows:
- Nozzle
- Runner and buckets
- Casing
- Breaking jet
Nozzle
The amount of water striking the buckets of the runner is controlled by providing a spear in the nozzle. The spear is a conical needle that is operated either by a hand wheel or automatically in an axial direction depending upon the size of the unit. When the spear is pushed forward into the nozzle, the amount of water striking the runner is reduced. On the other hand, if the sphere is pushed back, the amount of water striking the runner increases.
Runner and buckets
The runner or blade consists of a circular disc on the Periphery of which several buckets evenly spaced are fixed. The Shape of the bucket is a double hemispherical cup or bowl. Each bucket is divided into two symmetrical parts by a dividing wall which is known as a splitter.
Casing
The function of the casing is to prevent the splashing of the water and to discharge water to the tailrace. It also acts as a safe ground against accidents. It is made of cast iron or fabricated steel plates.
Breaking jet
When the nozzle is completely closed by moving the spear in the forward direction, the amount of water striking the runner reduces to zero. The runner due to inertia goes on revolving for a long time. To stop the runner in a short time, a small nozzle is provided which directs the jet of water to the back of the vanes. This jet of water is called a breaking jet.
Turgo Turbine Working Principle
A Turgo runner looks like a Pelton runner split in half. For the same power, the Turgo runner is one-half the diameter of the Pelton runner, and so twice the specific speed. The Turgo can handle a greater water flow than the Pelton because exiting water doesn’t interfere with adjacent buckets. The working operation of a Turgo turbine is very similar to the Pelton turbine.
In the Turgo turbine, high-speed jets of water emerge from the nozzles that surround the turbine. These nozzles are arranged so the water jet will hit the buckets on one side at an angle of around 20°. This shallow angle allows the water stream to exit on the other side instead of being diverted backward. Since the incoming and outgoing jets don’t interfere as they do in Pelton turbines, this Turgo turbine can accommodate a higher flow rate.
Advantages of Turgo Turbine
The advantages of Turgo Turbine are the following:
- Turgo turbine is very easy to assemble.
- There is no cavitation because the water jet strikes only a specific portion of the runner.
- It has fewer parts as compared to Francis’s turbine which has both fixed vanes and guided vanes.
- The overall efficiency is moderate.
- Both the first law and the second law of motion are applied.
Disadvantages of Turgo Turbine
Following are some disadvantages of Turgo Turbine:
- In Turgo Turbine, the size of the runner, generator, and powerhouse required is large.
- The variation in the operating head is a little difficult to control because of moderate heads.
Applications of Turgo Turbine
These are some applications of Turgo Turbine which are listed below:
- Turgo Turbine is the preferred turbine for hydropower when the available water source has a relatively high hydraulic head at low flow rates.
- In a hydroelectric power plant, this is used to drive the generator of the turbine and that generator generates the mechanical energy of the turbine into electrical energy.
Video on the assembly of Turgo Turbine
More Resources
Pelton Wheel Turbine
Francis Turbine
Hydraulic Tubine
Kaplan Turbine
Draft Tube
Media Credit
- CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=124419 [Image]
- Kris Harbour Natural Building [Video]
