Turboramjet

The air turborocket is a form of combined-cycle jet engine. The basic layout includes a gas generator, which produces high pressure gas, that drives a turbine/compressor assembly which compresses atmospheric air into a combustion chamber. This mixture is then combusted before leaving the device through a nozzle and creating thrust.

There are many different types of air turborockets. The various types generally differ in how the gas generator section of the engine functions.

Air turborockets are often referred to as turboramjets, turboramjet rockets, turborocket expanders, and many others. As there is no consensus on which names apply to which specific concepts, various sources may use the same name for two different concepts.

The benefit of this setup is increased specific impulse over that of a rocket. For the same mass of fuel as a rocket motor, the overall output of the air turborocket is much higher. In addition, it provides thrust throughout a much wider speed range than a ramjet, yet is much cheaper and easier to control than a gas turbine engine. The air-turborocket fills a niche (in terms of cost, reliability, ruggedness, and duration of thrust) between the solid-fuel rocket motor and gas turbine engine for missile applications.

A turborocket is a type of aircraft engine combining elements of a jet engine and a rocket. It typically comprises a multi-stage fan driven by a turbine, which is driven by the hot gases exhausting from a series of small rocket-like motors mounted around the turbine inlet. The turbine exhaust gases mix with the fan discharge air, and combust with the air from the compressor before exhausting through a convergent-divergent propelling nozzle.

Once a jet engine goes high enough in an atmosphere, there is insufficient oxygen to burn the jet fuel. The idea behind a turborocket is to supplement the atmospheric oxygen with an onboard supply. This allows operation at a much higher altitude than a normal engine would allow.

The turborocket design offers a mixture of benefits with drawbacks. It is not a true rocket, so it cannot operate in space. Cooling the engine is not a problem because the burner and its hot exhaust gases are located behind the turbine blades.

The air turboramjet engine is a combined cycle engine that merges aspects of turbojet and ramjet engines. The turboramjet is a hybrid engine that essentially consists of a turbojet mounted inside a ramjet. The turbojet core is mounted inside a duct that contains a combustion chamber downstream of the turbojet nozzle. The turboramjet can be run in turbojet mode at takeoff and during low-speed flight but then switch to ramjet mode to accelerate to high Mach numbers.

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