Nepedia
Back to Discover
Advanced Reader
💻

Turbine

technology Maturity 9-11 Next article →

A turbine is a rotary mechanical device designed to extract energy from a fluid flow. This fluid can be a gas, steam, or water. The machine converts the energy found in the moving fluid into useful work. In many modern systems, this rotational energy is used to drive a generator to produce electrical power.

Turbines impulse v reaction
Turbines impulse v reaction

The core of a turbine is the rotor assembly. This assembly consists of a shaft or drum with several blades attached to it. As a working fluid flows past these blades, it exerts a force that causes the rotor to spin. This process transfers energy from the fluid to the mechanical parts of the machine. To control the fluid, turbines often use a casing around the blades. This casing helps contain and direct the flow to ensure the energy transfer is efficient.

There are two primary ways a turbine can extract energy: through impulse or reaction. An impulse turbine works by changing the direction of a high-velocity fluid jet. The fluid is accelerated through stationary nozzles before it hits the moving blades. This process causes a change in the fluid's velocity, but not its pressure, as it passes through the rotor. Examples of this design include Pelton wheels and de Laval turbines. These machines are often most efficient when the fluid flow is low but the inlet pressure is very high.

A reaction turbine operates differently by reacting to the fluid's pressure or mass. In these machines, the fluid pressure changes as it moves through the rotor blades. Because of this pressure change, reaction turbines require a pressure casement to contain the fluid. This casing is essential for steam turbines or for water turbines that must maintain suction through a draft tube. Francis turbines and most modern steam turbines use this reaction principle. Reaction turbines are generally better suited for higher flow velocities or lower upstream pressure.

Dampfturbine Montage01
Dampfturbine Montage01

Modern engineering often combines both methods. Many steam turbines use both impulse and reaction stages in a single unit. Designers can vary the degree of reaction and impulse from the root of the blade to its outer edge. For example, in a steam turbine, the blades might be designed as impulse types at the base and transition to reaction types at the tips. This change happens because as the fluid expands at low pressure, the volume increases, and the rotation speed of the blade tips becomes much higher than the base.

The history of the turbine spans nearly two thousand years. Hero of Alexandria demonstrated the basic principle using a device called an aeolipile in the first century AD. Much later, in 1822, a French mining engineer named Claude Burdin used the word "turbine" in a formal memo. His student, Benoit Fourneyron, eventually built the first practical water turbine. The development of the steam turbine was driven by two key figures. Sir Charles Parsons invented the reaction turbine, while Gustaf de Laval invented the impulse turbine.

Gfa 17 641006 2-0002 Turbinen
Gfa 17 641006 2-0002 Turbinen

Today, turbines are vital to global infrastructure. Steam turbines drive generators in thermal power plants using coal, oil, or nuclear fuel.

Colbert Fossil Plant Tandem-Compound Turbine Rotor, US Space and Rocket Center, Huntsville, AL
Colbert Fossil Plant Tandem-Compound Turbine Rotor, US Space and Rocket Center, Huntsville, AL

They have also been used to power ships, such as the Turbinia, which was the first turbine-powered steam launch. In aviation, gas turbine engines provide the thrust needed for flight. Engineers use complex tools like computational fluid dynamics to optimize these machines. They also use the "specific speed" to determine the best turbine design for a specific power and flow rate.

Turbine inlet guide vanes of Atar turbojet
Turbine inlet guide vanes of Atar turbojet
573 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (6)
File:Dampfturbine Montage01.jpg
Dampfturbine Montage01.jpg
WWS Pneumaticlamp.ogg
File:Turbines impulse v reaction.svg
Turbines impulse v reaction.svg
File:Turbine inlet guide vanes of Atar turbojet.jpg
Turbine inlet guide vanes of Atar turbojet.jpg
File:Gfa 17 641006 2-0002 Turbinen.jpg
Gfa 17 641006 2-0002 Turbinen.jpg
File:Colbert Fossil Plant Tandem-Compound Turbine Rotor, US Space and Rocket Center, Huntsville, AL.jpg
Colbert Fossil Plant Tandem-Compound...
More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.