It's engines. Jet engines move the airplane forward with a great force that is produced by a tremendous thrust and causes the plane to fly very fast. All jet engines, which are also called gas turbines , work on the same principle. The engine sucks air in at the front with a fan. A compressor raises the pressure of the air. The compressor is made with many blades attached to a shaft.
The blades spin at high speed and compress or squeeze the air. The compressed air is then sprayed with fuel and an electric spark lights the mixture. The burning gases expand and blast out through the nozzle, at the back of the engine. As the jets of gas shoot backward, the engine and the aircraft are thrust forward. As the hot air is going to the nozzle, it passes through another group of blades called the turbine. The turbine is attached to the same shaft as the compressor. Spinning the turbine causes the compressor to spin.
The image below shows how the air flows through the engine. The air goes through the core of the engine as well as around the core. This causes some of the air to be very hot and some to be cooler. The cooler air then mixes with the hot air at the engine exit area. Thrust is the forward force that pushes the engine and, therefore, the airplane forward.
Sir Isaac Newton discovered that for "every action there is an equal and opposite reaction. The engine takes in a large volume of air. The air is heated and compressed and slowed down. The air is forced through many spinning blades. By mixing this air with jet fuel, the temperature of the air can be as high as three thousand degrees.
The power of the air is used to turn the turbine. Finally, when the air leaves, it pushes backward out of the engine. This causes the plane to move forward. Parts of a Jet Engine. Fan - The fan is the first component in a turbofan. The large spinning fan sucks in large quantities of air. Most blades of the fan are made of titanium. It then speeds this air up and splits it into two parts. One part continues through the "core" or center of the engine, where it is acted upon by the other engine components.
The second part "bypasses" the core of the engine. It did not fly much, but it was a strong first step. At the same time, British innovator Frank Whittle developed his own jet engine, which was used in the Gloster Meteor.
It was occasionally deployed as a defensive measure, but its relative lack of speed made it impractical for overseas combat. After the war, the application of jet engines turned to passenger airlines. Once this was achievable, jet travel became much cheaper and more accessible. The jet age is generally accepted as beginning in , when the now-defunct Pan American Airlines began overseas jet service on Boeing s.
At the front of a jet engine, a fan sucks in air. If you look head-on at a jet engine on a passenger jet aircraft, you can see the blades of this fan. The air is then retained inside the engine, where a compressor places it under pressure. The compressor contains more fans, all of which are fitted with blades and fastened to a shaft. After these fans have done their work of compressing the air, fuel is introduced. A spark is then ignited, causing the mixture of fuel and air to burn.
This combination then rapidly expands and is directed through a nozzle, which is placed at the back of the engine. This concentrated energy is the thrust which propels the airplane. The reaction takes place with extreme speed and the turbines in most modern jet engines spin over 10, times a minute.
What is in fuel mixture which causes this powerful reaction? Jet fuel is technically known as aviation turbine fuel, or ATF. While initial jet engine experiments used steam power and early piston engines ran on gasoline.
ATF is usually clear or light yellow. It consists of a mixture of hydrocarbons, and for safety reasons is processed with international specifications and standards. In commercial aviation, most jet engines use fuels known as Jet A and Jet A Most general aviation airplanes using turbine engines use a compound called Jet B, a performance type which is specifically designed for cold weather. However, they are inefficient, and jet fuel is expensive.
In many engines the compressor is responsible for both sucking in the air and compressing it. Some engines have an additional fan that is not part of the compressor to draw additional air into the system.
The fan is the leftmost component of the engine illustrated above. The compressor is shown in the above image just to the left of the fire in the combustion chamber and to the right of the fan.
The compression fans are driven from the turbine by a shaft the turbine is in turn driven by the air that is leaving the engine. Compressors can achieve compression ratios in excess of , which means that the pressure of the air at the end of the compressor is over 40 times that of the air that enters the compressor.
At full power the blades of a typical commercial jet compressor rotate at mph kph and take in lb kg of air per second. Now we will discuss how the compressor actually compresses the air. As can be seen in the image above, the green fans that compose the compressor gradually get smaller and smaller, as does the cavity through which the air must travel. The air must continue moving to the right, toward the combustion chambers of the engine, since the fans are spinning and pushing the air in that direction.
The result is a given amount of air moving from a larger space to a smaller one, and thus increasing in pressure. BANG In the combustion chamber, fuel is mixed with air to produce the bang, which is responsible for the expansion that forces the air into the turbine. The motor is bolted to the outside of the engine and uses a shaft and gears to connect to the main shaft.
The electric motor spins the main shaft until there is enough air blowing through the compressor and the combustion chamber to light the engine. Fuel starts flowing and an igniter similar to a spark plug ignites the fuel.
Then fuel flow is increased to spin the engine up to its operating speed. If you have ever been at the airport and watched a big jet engine start up, you know that the blades start rotating slowly. The electric starter motor does that. Then you sometimes hear a pop and see smoke come out of the back of the engine. Then the engine spins up and starts producing thrust.
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