- A jet engine is made up of basically four main parts: the intake, the compression, the combustion and the exhaust. The intake occurs through the intake nacelle at the front of the jet engine. Air flows into the nacelle and strikes the compressor blades and starts turning them, thus drawing in more air into narrower and narrower blades and compressing the inflowing air. The jet engine has at the intake a set of turbine blades that are fashioned to draw the air in. The blades increase in pitch so that air that has been drawn in is compressed and is under high pressure as it travels past the intake turbine blades.
- This highly compressed air then passes into the next chamber that has fuel injected into it and is burned. The compressed air flowing through this chamber acts as a catalyst to provide oxygen for the burning fuel. A jet engine works by taking air in (intake) and expelling (exhaust) it under more force than under which it came in. Next, this pressurized air mixed with fuel, which is burning into the combustion chamber in roughly the center of the turbine assembly, is then expelled out the exhaust of the jet engine.
- Unlike the internal combustion piston engine, the fuel is not ignited by a timed ignition sequence; rather, it is continually burned as the compressed air flows through the chamber and becomes the catalyst to enable the fuel to continue burning. It is for this reason that jets can actually burn a lower octane fuel than cars or radial engine propeller-driven airplanes. Once the air and fuel mixture ignites, the resulting expansion of gases drives the exhaust turbines as the gases are expelled out the rear of the turbo jet, creating the thrust of the jet engine.
- Newton's third law of physics, that every action has an equal and opposite reaction, comes into play here. Once the fuel burns, the super-heated expanding air is forced out of the exhaust of the jet engine, which is then moved in the opposite direction--that is, forward.
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