Airborne applications of Gas turbines

After having understood the importance of gas turbines, they are used  for a wide range of airborne, land and marine applications. The airborne applications of gas turbines include the widely known turbojets, turbofans and turbo propellers.
. The gas turbines used for land and marine applications are called mechanical drives. Before we begin to understand where they are used let's have a basic idea of them.
All the three applications have the same structure as that of the gas turbine but differ only on the areas where they are used and addition of a single component. In a turbojet, the gases which are expanding through the nozzle after combustion is directly converted to thrust which is responsible for the motion of the aircraft.
 In case of turbofans, the gases expand through the nozzle and a certain portion of it is converted to thrust while the remaining portion is used for the fan to accelerate the flow of air rearwards.
Turbofan

Turbofans produce less noise and are much more efficient compared to turbojets. The fan here is responsible for producing some thrust. However in turboprops all of the energy is used for driving the propeller attached on the front side and no thrust is created.
Turboprop

Most modern day airliners use turbofans because they are fuel efficient and can produce thrust from the fan as well as from the engine. They are reliable and much quieter. Turboprops and turbojets are used for military applications.

Rolls Royce Trent 1000
You may find two different types of engines on an aircraft such as Trent 1000 on one side and Pratt&Whitney on the other.

The Airbus 380 uses two different types of turbofan engines which is now used by Emirates, Singapore Airlines, Lufthansa. The Boeing 787 is also a turbofan engine widely used by Qatar Airways, United Airlines, Etihad Airways and many more.

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