How Many Types Of Jet Engine Are There?

in this video we will look at the different types of design of jet propulsion from fighter jet to helicopters there are different types of jet propulsion so how many types of jet propulsion are there and what are they in another video we described the basics of how a jet engine worked we won't go into too much detail again here but it is worth reminding you of some of the aspects as it will be relevant later in this video the essence of all designs is that hot air from the combustion chamber will flow over the turbines and cause them to rotate the turbines are connected to the dry shaft this causes the drive shaft to rotate the drive shaft not only turns the compresses but will also power other aspects of the engine which we will discuss later so how many basic types of jet engines do we have there are basically four types the turbo jet the turbo fan the turboprop and the turboshaft firstly we will look at the turbojet the turbojet was the first design of engine and is usually incorporated into military fighter jets the turbojet's thrust is derived purely from the hot exhaust gas which is directed out of the rear exhaust nozzle the advantage is that the design of the engine is slimmed down which is perfect for fitting into fighter jets another advantage is that all of the hot exhaust gas which makes up all of the thrust can be directed into the reheat system or afterburners as the americans call it the turbojet has disadvantages in that it can be very noisy and is not as fuel efficient as the turbofan not what you'd want in a modern airliner the next section to discuss is the turbofan the turbofan is fitted to modern airliners and continuing design improvements are massively increasing fuel efficiency and reducing noise levels the design of the turbo fan is similar to any other jet engine in that it has turbines combustion chambers a drive shaft and compresses the difference being the turbofan engine has a series of large fan blades at the front of the engine which makes up the fan the fan acts as a very powerful propeller and ninety percent of the engine's thrust is produced by the fan the rest of the engine is known as the core the airflow from the fan travels around the outside of the core and out through its own exhaust at the back the hot air from the core produces about 10 percent of the thrust later designs such as the airbus neo have a smaller core design which enables the fan area to be increased this has led to greater efficiency of the engine modern airliners have reverse thrust fitted the reverse thrust mechanism diverts the airflow from the fan to the outside of the engine and points the airflow forwards whilst the core is still producing forward thrust the net gain of diverting the fan's airflow is to give a 25 to 30 percent braking thrust the next section to discuss is the turboprop turboprop aircraft are still in use today and are very good at the shorter routes whilst turbojet and turbofan aircraft are more efficient at higher levels turboprops are efficient at low to medium levels the turboprop structure is very similar to the turbojet and turbofan engines it still has the turbines the combustion chambers compresses and driveshaft there are actually two drive shafts one inside the other one driveshaft is connected to the inner turbines and drives the compresses the other drive shaft is driven by the outer turbines and connects to a gearbox the gearbox in turn is connected to a propeller the gearbox's job is to reduce the cause rpm to a suitable level for the propeller to operate the propeller rpm is maintained at a constant speed which is selected by the pilot by a constant speed unit this works by automatically changing the propeller pitch angle for a given power setting it also provides a reverse thrust setting when selected by the pilot fortunately we will not go into detail at this point the final section of this video deals with the turboshaft engines turboshaft engines are mainly found on helicopters the main section of the turboshaft engine the core will contain the same components as the other types of engine such as the compressors combustion chambers and turbines similar to the turboprop the turboshaft will have a separate turbine called the free or power turbine which is connected to a separate drive shaft called the power shaft unlike the turbo prop the power shaft will exit through the rear of the engine so that it can connect to the gearbox assembly this is explained later the exhaust is therefore channeled out through the side on dual engine helicopters there is usually only one exhaust port because the power shaft is connected to a main rotor gearbox the free turbine and power shaft are designed that in the event of an engine failure they do not create any significant drag on the gearbox system this diagram shows a basic design of a helicopter main gearbox the power shaft from the engine will connect to the gearbox as shown the gearbox gearing assembly will then reduce the rpm from the engine and will then drive the rotor shaft which turns the rotor blades so in this video we have discovered that there are four types of jet propulsion these are turbojet turbofan turboprop and turboshaft all are in use in today's aviation thank you for watching and please stay tuned for the next exciting video from the aviator

Channel: The Aviator

Views: 54,218

Keywords: Turbofan, turbojet, turboprop, turboshaft, jet, jet engine, propulsion, aviation

Id: xBqXiCMGlXk

Length: 7min 10sec (430 seconds)

Published: Thu Dec 17 2020