Just like we recently discussed about turboprops and afterburners, we will then give continuity to the theme now approaching a little more about a type of engine little used in aviation and that some say does not even look like a real engine.
In the basic principle, a RamJet engine does not contain moving parts, it is not the same configuration as for example a turbofan or a turbojet in that it contains fins that help in the compression and decompression of the gases, unlike engines with moving parts, the Ram Jet does not it can create its own wind acceleration, so it is used when the aircraft is already at a higher speed that allows for burning inside its chamber.
It can be divided into 3 parts, the air intake, the compressor and the nozzle, on the compressor or before it are located the injector nozzles that are responsible for mixing the right amount for the speed of the aircraft (another point, in a turbofan is according to the rotation and analysis of the sensors).
It is a type of engine immensely designed to fly at supersonic speeds, to give you an idea, up to half the speed of sound it is inefficient to use, as it cannot generate the necessary air pressure for combustion to occur. This happens because the burning occurs through the formation of air pressure in the air intake of the engine, its normal speed at which it is activated is above the speed of sound, that is, mach 1, being more usable from mach 2 upwards, than Likewise, it is not as efficient above mach 5 because the pressure formed in its mouth is extremely excessive.
From this variant, another 2 arise, one to be used in the stratosphere and another that even allows accelerating a space probe to speeds close to light.
scramjet
Variant that allows flights above Mach 5 by being able to burn at supersonic speeds (on the Ramjet it flies at supersonic but burns at subsonic by decompression), it is a clever way to be able to fly on Earth at speeds close to MACH 25 in some projects or 25000 km/h, the equivalent of going around the planet Earth every 96 minutes, this is almost faster than the International Space Station manages to make its orbit. OO
It was already considered to be used in space shuttles, but it was abandoned because it did not prove to be as efficient as a normal rocket engine, predicting that it could burn hydrogen instead of the oxygen that the space shuttle carried in its external tanks.
In a test, NASA's X-51A was the protagonist, a B-52 took the aircraft into flight and soon after released it, the X-51A accelerated to mach 4,5 by rockets and successfully activated its Scramjet system.
Bussard Ramjet
It is a type of propellant proposed in the 60s (very late) as an alternative to getting close to the speed of light using nuclear fusion, which is why it is also known as a nuclear fusion rocket. It relies on small amounts of hydrogen present in the interstellar medium, it has a large size which allows it to capture a sufficient amount to move through electromagnetism, the material goes to a rocket in the style of the Ramjet, it is very similar.
Like most suggestions, this one did not go ahead.
