Jet engines have played a very important role in our advancement.
We’re not just talking about the aeroplanes but jet engines gave inspiration to the rocket engines which took us to the moon andwithout them the space voyages were not have been possible.
Jet engines are not the same like a car engine which actually uses the combustion process to move the crank shaft to produce the rotary motion.
Rather the jet engines actually ingest the air from outside and produce power and exhaust the gases which are a mixture of the air which was taken in and the fuel to produce proper motion.
We would be going into the details of jet engine working below.
Basics of a jet engine:
The jet engine actually works on Newton’s third law of motion that is to every action there is an equal and opposite reaction.
In many of today’s technologies this principle is used like it is used in the jet engines. We would be looking into the practical application of this law in greater detail below to understand how it powers the jet engines.
Here the action which we are talking about is the exhaust of the gases from the jet engine which produce a force which causes the reaction in the form of the thrust of the jet engines in the forward direction.
This same working principle is used by you plenty of times in a skateboard when you click backward to produce the forward thrust.
How does a jet engine work?
To understand the basic working of the jet engine you had to 1st understand the diagram which we have presented above.
1.In most of the cases when we are talking about a jet engine you would realise that this is a jet engine which is going slower than the speed of sound because there are very few jet engines in the world which are propelling the plane at a speed which is greater than song. For the sake of this explanation and for the sake of simplicity we would be explaining the jet engine which goes below the speed of sound which is 1000 km/h. For the sake of explanation we had to consider the jet engine is being stationary and the air is actually moving towards the jet engine.
2. The fan which is at the front of the jet engine ingests the air into the engine.
3. If you looked at the border diagram carefully then you would notice that behind the first fan there is another fan and this is actually used to is the air which is ingested by the first fan. The rate of compilation is by eight times. Which now makes the speed of the air to around 400 km/h.
4. The jet fuel is now introduced into the engine in small quantities from a fuel tank which is inside the wing of the plane.
5. After the compression of the air which is ingested by the first fan and compressed by the second find the air now moves into the combustion chamber in which the fuel is also introduced. Due to the highly inflammable nature of the fuel it starts burning fiercely and the temperature can rise up to 90 0°C. Due to this burning of the fuel there are exhaust gases which are generated as well.
6. Behind the combustion chamber or the turbine blades which are like the blades of a wind turbine and when the exhaust gas most through these blades they start spinning rapidly.
7. The turbine blades are directly in connection with the compressor and the main fan which is at the start of the engine and therefore when the turbine blades rotate due to the connection with the help of the axle, the first fan and the compressor fan also start rotating and thereby taking in more air inside the engine and continuing the entire process.
8. The exhaust gases are not directly thrown out of the engine but there is actually a tapering end towards the end of the engine which is actually known as exhaust nozzle. In the tapering and as the spaces low the speed of the exhaust gases actually increases to over 2100 km/h or 1300 mph. Due to the force of the exhaustion of these cases the plane starts to move forward. If you would have noticed the speed of the exhaustion of these gases is double that of the required speed of the plane this is because the plane has to carry the weight of the fuselage and also the passengers and also the car go along with that that is why the gases are made to exhaust at such a high temperature. If the speed of the plane which is needed is more than the speed of sound then just before exhaust nozzle there is an afterburner as well and this can be seen in the military planes especially and this further introduces fuel to the exhaust gases which further increases the speed of the exhaust gases due to the burning of the fuel. This increases the speed of exhaust of the gases and therefore the plane is able to move at a speed which is even greater than the speed of sound.
Different types of jet engines:
If you notice the different types of plane then you would already be knowing that the type of engines in those planes are different in some of the instances and some of the engines which you might have noticed would be the turbojet engine and also the turboprop engine.
The turbojet engine is the one which you we have explained in the working principle of the jet engine about and it is one of the most oldest type of engines and is still in use these days and for general-purpose aviation turbojet engine is still widely preferred.
In this type of engine the propeller is in front of the engine and not inside the engine and also it is driven by the engine which is directly behind the propeller and also this kind of engine is used in the smaller aircraft which do not need a large amount of thrust and these type of aircraft are actually used in the economical operations where the Lord which is to be lifted and the weight of the plane is not very high. You can say that these type of engines are used in the smaller planes which do not have to carry a lot of cargo or passengers. These are also used in the helicopters as well.
Turbofan engine is actually an advancement over the turbojet engine and in this the size of the fan is much greater and therefore there is a large amount of ingestion of the air into the engine but not all of this air actually goes inside the combustion chamber because some of it is directly exhausted by moving it around the combustion chamber and the advantage of this assembly is that it keeps the engine cool during the process and therefore the noise which is generated by this type of engine is also on the lower side. Due to the continuously cooling assembly the thrust which is generated by this type of engine at landing as well as takeoff is much greater than the turbojet option as well.
Scramjets and Ramjets:
These are more less like gas burning pipes and the only difference between ramjet and scramjet is that scramjet actually travels at supersonic speed whereas ramjet is actually travel at below the speed of sound. These are used in missiles as well as rockets.