INTEGRATED DIRECT-FLOW AIR-JET ENGINE Russian patent published in 2023 - IPC F02K7/18 

FIELD: aviation; engines.

SUBSTANCE: proposed device relates to jet engines, in particular to integral (combined) ramjet engines (ramjet), and is designed to equip disposable and reusable aircraft. The task to be solved by the proposed device is to increase the reliability and efficiency of the propulsion system, to ensure the possibility of multiple use of aircraft with a ramjet. The integrated ramjet engine includes a main ramjet engine and a starting liquid propellant engine (LPE) located in its combustion chamber. The section of the LPE nozzle exit is in the plane of the critical section of the propulsion ramjet. The nozzle exit area of the launch rocket engine is less than the critical section area of the propulsion ramjet engine by the size of the air intake throat area. In the acceleration mode of the aircraft, the launch rocket engine operates. The air passing through the ramjet chamber passes through the annular gap formed by the LPE nozzle exit and the critical section of the ramjet. In the expanding part of the ramjet nozzle, a nozzle with a break in the supersonic contour is formed. After the end of the acceleration of the aircraft to the cruising speed of the ramjet, the LPE is moved to the front of the ramjet chamber, it is turned off and fixed. The LPE fuel supply system can be used to spray it into the ramjet combustion chamber in addition to the ramjet's own fuel supply system.

EFFECT: reusable engine, higher specific impulse of the accelerating engine compared to solid propellant rocket motors, decrease in the aerodynamic resistance of the air intake device in the accelerating section of the flight, and an increase in reliability due to the absence of destructible nodes.

2 cl, 2 dwg