I have described information about Aircraft engines on another part of this entry. If you have not read that yet please do.
Jet engines allow us to go faster and fly higher then what piston engines could achieve. Yet their operation is more simpler to understand then the piston engines. A jet engine is broken up into 2 sections. They are called the Hot Section and the Cold section. The cold section is usually located in front, and the hot section is in the rear. As air enters the engine is first compressed, them mixed with fuel, ignited, and then released through the back. This whole chain of events is called the constant pressure cycle.
There are 2 major types of jet engines, Axial, Centrifugal. They are named differently because of the type of compressor they use. A Centrifugal compressor uses an impeller rotating in a defuser. This impeller wheel throws air outward because of centrifugal forces on the air as it spins. The air is then caught by the defuser which increases the pressure and sends into the next stage. The other type of compressor uses blades built up in stages. These stages contain first a rotor then stator as one stage. The rotor spins and the stator is stationary. As it spins it "pulls" air into the stator like a fan. The stator compresses it and delivers the air to the next stage at the proper angle. There can be many stages in one engine. Each stage increasing the pressure. The compressor is known as the cold section of the engine, because the temperatures are relatively lower then the other part of the engine.
The next step the air takes after it has been compressed is the burner cans. Here fuel is mixed with the compressed air and then ignited. The hot flame that is produced contained by compressed air around the burners. When the fuel air mixture is burned it expands and exits through the back. There are 3 types of burner cans, Annular, Can annular and can type. These three types differ in shape. There are usually about 8 or 9 burner cans in a jet engine. If you have the annular type burner then you only need one. When it is exiting through the back it passes through another set of fan blades called turbines. When the gases pass through they force the turbines to turn and produce power. This power is then used to spin the compressor.
The last stage on the jet engine is the exhaust stage. Here all the hot exhaust gases are collected and straightened out into a uniform jet stream in which velocity is further increased. This action produces thrust for the aircraft.
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