A turbojet engine is a gas turbine device in which thrust is created by converting energy (thermal) into kinetic gas flow. In this case, the resulting reaction is used as a driving force.
The most widespread and effective turbojet engine received in aircraft, which are capable of developing high flight speeds (supersonic aircraft).
There are single and double-circuit devices that are equipped with afterburners, which significantly increase the take-off and flight thrust. At the same time, with a higher thrust index, the flight speed increases.
The widespread use of turbojet engines is due to the relative simplicity of their device and low specific gravity. The unit consists of a combustion chamber, a turbine, a compressor and an exhaust nozzle representing a constriction pipe, which is located inside the exhaust manifold.
The air in the intake acquires a preliminary increase in pressure (due to high-speed pressure), which then rises in the compressor. This allows you to create favorable conditions for combustion processes and the efficient use of heat. The permissible temperature at the entrance to the gas turbine depends on the heat resistance of the materials and the cooling efficiency of the turbine. An increase in air pressure and gas temperature is a characteristic feature of most types of gas turbine devices.
The turbojet engine used in unmanned and high-speed aviation provides a significant increase in thrust in afterburner modes, and, consequently, in traction power when supersonic speed is reached. However, the units used in the field of subsonic flights are inferior to other types of gas turbine engines in terms of traction and economy.
This circumstance is due to the principle of operation of the device, which is associated with a relatively high loss of heat and high-speed energy with an exhaust stream at low flight numbers (M).
It is not easy to assemble a turbojet engine with your own hands, for this it is necessary to thoroughly know its structure and the principles of operation of all elements.
The device includes a gas compressor system , which is located between the chambers and the inlet. Thanks to the energy generated as a result of fuel combustion, the turbine drives the compressor and provides traction.
Detailed diagrams and calculations of the components of the propulsion system, as well as piston engines, are very diverse. In various sources you can find detailed calculated data and simple descriptions for these systems, which allows you to make a homemade turbojet engine.
Units in which centrifugal pumps are installed do not have an afterburner. Gases leaving the turbine enter the jet nozzle, after which they expire into the atmosphere at high speed. The thrust is created by increasing the speed of the gases exiting the engine.