Rocket-based combined cycle engine

Abstract

The invention relates to a rocket-based combined cycle engine. The rocket-based combined cycle engine comprises a shell body, an air inlet, a central cone, a rocket combustion chamber, a supersonic-combustion combustion chamber and a supersonic-combustion spray pipe. The air inlet and the supersonic-combustion combustion chamber are arranged in the shell body sequentially, the central cone is arranged in the air inlet, the tail end of the central cone is connected with the rocket combustion chamber, and the tail end of the rocket combustion chamber is connected with the plug-type spray pipe. The rocket combustion chamber comprises a cylindrical shell and a rocket combustion chamber inner core arranged in the cylindrical shell, wherein one end of the cylindrical shell is connected with thecentral cone and is in smooth transition connection with the central cone; one end of the rocket combustion chamber inner core is connected with the central cone; and the rocket combustion chamber inner core coincides with the central axis of the cylindrical shell. Incoming flow air enters the supersonic-combustion combustion chamber from an inlet of the air inlet through the air inlet, and the tail end of the supersonic-combustion combustion chamber is connected with the supersonic-combustion spray pipe. According to the rocket-based combined cycle engine, a traditional rocket engine bell-shaped spray pipe is changed into the plug-type spray pipe, and it is guaranteed that the engine has higher performance in a wide range by utilizing the automatic matching characteristic of the plug-typespray pipe and ambient pressure.

Description

technical field [0001] The invention relates to a combined cycle engine in the field of aerospace, in particular to a rocket-based combined cycle (Rocket-Based Combined Cycle, RBCC for short) engine including an air-breathing ramjet. Background technique [0002] To achieve hypersonic flight (usually the flight Mach number is greater than 5, and the Mach number refers to the ratio of the flight speed to the speed of sound) the power unit can use a rocket engine or a scramjet. Rocket motor technology is mature and can work in and out of the atmosphere. Because the rocket engine must carry all oxidants and fuels, the specific impulse is very low (the specific impulse refers to the total impulse produced by the unit mass propellant, which is the most important indicator of the performance of the reaction engine. As known in the art, the liquid oxygen kerosene engine The specific impulse is less than 3000N.m / s). Scramjet uses oxygen in the air as the oxidant, has the advantage...

AI Technical Summary

Problems solved by technology

[0003] The main disadvantage of the scramjet engine is that the engine cannot work at low speeds, and external power is required to boost the aircraft to the relay Mach number (that is, the Mach number at which the ramjet engine starts to work)

The problem of the mismatch between the center rocket gas and the outer air is that if the pressure of the rocket is too high, it will expand outwards and squeeze the air, causing the inlet to not start; It will form a shock wave at the exit of the rocket engine, causing the performance of the engine to decline.

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