With the vast majority of energy generation and fluid delivery, a turbine is of different types serving the same purpose in various applications. It is a device that harnesses the kinetic energy of some fluid such as water, steam, air, or combustion gases. It turns it into the rotational motion of the device itself. The device is further connected to a generator that generates electrical power, or it can be used for mechanical work.
Today, you’ll get to know the different turbine types, their diagram, and working principles.
Read more: Things you need to know about turbine
Types of turbine
Below are the various types of turbine
Impulse and reaction turbine
Impulse and reaction turbines are turbines used in hydroelectric powerplants. They are water turbines that have water as their working fluid. In their work, millions of liters of water are collected from a dam, the height of the dam determines the pressure at which the water flows. The highly pressurized water is allowed to flow through a large pipe called a penstock.
The turbine is located at the end of the penstock, giving the pressurized water easy access to strikes the blades of the turbine at high velocity, causing it to rotate. Electricity is generated when the turbine is further connected to a generator. One of the basic differences between impulse and reaction turbine is the shape of the turbine blades
An impulse turbine basically works under the principle of Newton’s 2nd law. Instead of blades on the rotor hub, a number of the elliptical half-sized buckets are fitted. So, when water strikes the buckets at high speed, the rotor starts rotating, this means, the kinetic energy of water gets converted into rotational mechanical energy. Therefore, electricity is generated when one end of the turbine shaft is connected to the generator. Examples of an impulse turbine include Pelton, Turgo, and Cross-flow.
In a reaction turbine, the sum of potential energy and kinetic energy of water due to the pressure and velocity, respectively causes the turbine blades to rotate. The entire body of this turbine is immersed in water and changes in water pressure along with the kinetic energy of the water cause power exchange. Applications of this turbine are usually at lower heads and higher flow rates than impulse type.
Steam turbine types are often used in nuclear and thermal power plants. Water is heated to produce steam when then flows through a turbine to produce electricity. A steam turbine can also be classified into impulse and reaction types especially modern ones. The difference between this turbine is that the arrangement and design are different.
Steam turbines consist of rotating blades called rotors and static blades called stators. These two components are placed alternately in order to extract the most energy out of it. This process is known as compounding. In an impulse turbine, its moving buckets are designed to get pushed by the steam. While the rotor blades in reaction turbines are aerofoiled in shape, which lets itself generate reaction and also lets steam maintain its velocity.
In most steam turbines, the steam first flows through high pressure (H.P) turbine followed by intermediate pressure (I.P) turbine. After reheating the steam, it then flows through low pressure (L.P) turbine (huge set of blades). The purpose of the increase in blade sizes from the inner side to the outer side is because steam expands while losing its pressure and kinetic energy.
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Gas turbines are often used in heat engines, which is why they are also called internal combustion engines. They are one of the most flexible types of turbines, making their application broad. It is used in powerplants for generating electricity and also used for propelling airplanes and helicopters. The system has an axial compressor at the inlet, which are sets of rotating blades. These blades suck a huge amount of air and compress it in order to increase the temperature of the air. The air is further supplied to the combustion chamber. In the working of these types of turbines, fuel is added into the combustion chamber and an ignitor ignites the fuel. Therefore, a large amount of exhaust gases is produced which are made to flow through turbines.
The different types of gas turbines/jet engines are:
The invention of a wind turbine has benefited mankind as it is known as a clean method of generating electricity. Just like other types of turbine, a wind turbine has three blades and are designed to rotate when wind flows straight through them. Wind turbines rotate at a very low RPM, which can’t produce electricity of the required frequency. This is why a gearbox is required in the system to increase the speed of the shaft. The output is what is connected to the generator that produces electricity.
In another word, wind types of turbines operate by transforming the kinetic energy in wind into mechanical power. This power is then used to generate electricity by spinning a generator. The turbine can be on land or can be offshore.
Read more: Understanding wind turbine
The 3 primary types of wind turbines are:
- Horizontal-axis wind turbines (HAWT)
- Savonius vertical-axis wind turbine (Savonius VAWT)
- Darrieus vertical-axis wind turbine (Darrieus VAWT)
That is all for this article, different types of a turbine which include impulse and reaction turbine, steam turbine, gas turbine, and wind turbine.
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