Jet engines have been the successful drivers of aircraft for nearly a century now in
we will explain the technology behind the jet engine in a logical step-By-step Manner
a jet engine keeps an aircraft moving forward using a very simple principle.
Yes, Newton's third law of motion just
The reaction force produced by the Air moves the balloon
The reaction force produced by the high-speed jet at the tail of the jet engine makes it move forward
so the working of the jet engine is all about producing a
High-speed jet [at] the exit the higher the speed of the jet the greater the thrust force
The thrust force makes an aircraft move forward
Such high-speed exhaust is achieved by a combination of techniques
If you can heat the incoming air to a high temperature it will expand tremendously and will create a high velocity.
For this purpose, a combustion chamber is used
An atomized form of the fuel is burnt in the combustion chamber
effective combustion requires air to be at moderately high temperature and pressure
To bring the air to this condition a set of compressor stages are used
The rotating blades of the compressor add energy to the fluid and its temperature and pressure rise to a level suitable to sustain combustion
Does the compressor receive the energy for the rotation from a turbine that is placed right after the combustion chamber?
The compressor and turbine are attached to the same shaft
The High-energy fluid that leaves the chamber makes the turbine blades turn
You can see that the turbine blades have a special airfoil shape which creates lift force and make them turn
As the turbine absorbs energy from the fluid its pressure drops
Through these steps, we have achieved our objective a really hot and high-speed air emitted from the exit of the engine
the engine case becomes narrower towards the outlet which results in even greater jet velocity
In short, the synchronized operation of the compressor combustion chamber and turbine makes the aircraft move forward
Modern aircraft use a slightly improved compressor turbine arrangement called a two-spool
Here two independent turbine compressor stages are used
the shaft of the outer compressor turbine passes concentrically through the inner one
The outer turbine is subjected to a low energy fluid and will run at a slower speed than the inner turbine
Low-pressure blades are longer this low-speed helps to reduce centrifugal stress induced at the root Thus improving the blades life
Some modern aircraft even use a three spool engine
The engine we have discussed so far is more specifically called a turbojet engine
Turbojet engines tend to produce high levels of noise
Revolutionary Improvement was made to this engine by fitting a large fan with the low-pressure spool
such engines are called Turbofan engines and almost every commercial aircraft run on them a
Turbofan engine bypass is a huge amount of air
The ever-narrowing bypass duct provides a good jet velocity to the bypassed air
in a turbofan engine, the majority of the thrust force comes from the fans reaction force
further, the fan greatly improves Airflow in the system by sucking in more air
Thus it helps to improve the thrust.
This means high thrust creation with an expense of slightly more fuel
This is a reason why Turbofan engines highly fuel economical
The noise produced by a jet engine is highly dependent on the exit jet velocity
Since in a turbofan the bypassed cold air gets mixed with the hot air it is possible to keep the outlet velocity within a limit.
Thus it overcomes the noise problem
With quieter exhaust and better fuel economy, the turbofan engines continued to dominate aircraft propulsion systems
We hope this provided a nice introduction to the working of jet engines.
Thank you
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