How does a jet engine work?
Jet engines move the airplane forward with a great force that is produced by a tremendous thrust and causes the plane to fly very fast. All jet engines, which are also called gas turbines, work on the same principle. The engine sucks air in at the front with a fan. A compressor raises the pressure of the air. The compressor is made up of fans with many blades and attached to a shaft. The blades compress the air. The compressed air is then sprayed with fuel and an electric spark lights the mixture. The burning gases expand and blast out through the nozzle, at the back of the engine. As the jets of gas shoot backward, the engine and the aircraft are thrust forward. The image below shows how the air flows through the engine. The air goes through the core of the engine as well as around the core. This causes some of the air to be very hot and some to be cooler. The cooler air then mixes with the hot air at the engine exit area.
The gas turbine, or jet engine, was the first alternative to the propeller as a means for providing thrust to move an aircraft through the sky. Like most engines, the jet is an internal combustion engine, which produces thrust through the classic four-stroke cycle; induction, compression, ignition and exhaust. But unlike propeller planes, which convert the superheated exhaust of internal combustion into mechanical power to drive a rotor, jet engine thrust comes directly from exhaust, ejected from the rear of the tube-shaped engine. While a propeller planes’ maximum speed is around Mach 0.8, a jetplane can reach speeds of Mach 15 or higher (see scramjet), though Mach 1.0 – 2.0 is more typical. The world’s first jet engine plane, the He 178, was designed during the late 30s by German engineer Hans von Ohain, and flown from Marienehe aerodrome by test pilot Erich Warsitz on August 27, 1939. England flew their first jet engine plane in 1941. American-born designs were not implemented until
A jet engine is an internal combustion engine with the same four stages as a piston engine, Intake, Compression, Ignition & Exhaust. However, unlike a piston engine which is a Four Cycle engine, a jet or turbine is a Continuous Cycle engine with all the steps taking place at the same time. At it’s simplest, air is taken in at the front, then compressed by the compressor blades at the front of the engine. Some of that air is then sent into the combustion chambers, where fuel is added and ignition takes place. This causes the air to heat up and expand rapidly, and it is exhausted over the turbine blades at the back of the engine. This turning turbine rotor drives the compressor rotor by a connecting shaft, drawing in more air and the cycle continues as long as there’s fuel available. A starter will spin the engine up to approximately 20% of it’s maximum speed to get the process going before the fuel is turned on. An ignitor plug, (like a big spark plug), is used to start the ignition pro
