Method for improving starting capacity of RBCC air inlet channel

Abstract

The invention provides a method for improving the starting capacity of an RBCC air inlet channel. The method for improving the starting capacity of the RBCC air inlet channel is applied to a rocket-based combined engine. The rocket-based combined engine comprises the air inlet channel, an isolation section, a combustion chamber and a built-in rocket; the initial chamber pressure of the built-in rocket is configured to be a first pressure value, and the outlet back pressure of the combustion chamber is configured to be a first back pressure value; and the working chamber pressure of the built-in rocket is sequentially reduced to a second pressure value and a third pressure value from the initial chamber pressure so as to reduce the starting mach number of the air inlet channel, and after the air inlet channel is started, the chamber pressure of the built-in rocket is restored to the first pressure value from the working chamber pressure so as to improve the starting mach number of the air inlet channel. When the air inlet channel is started, the chamber pressure of the built-in rocket is reduced by reducing the fuel quantity of the built-in rocket, so that the spanwise expansion radius of jet flow of the built-in rocket is reduced, the pressure intensity of the RBCC combustion chamber is reduced, then the starting mach number of the air inlet channel is reduced, and the self-starting capacity of the air inlet channel is improved.

Description

technical field [0001] The invention relates to the field of air-breathing combined propulsion systems, in particular to a rocket-based combined cycle engine. Background technique [0002] The Rocket-Based Combined Cycle (RBCC) engine organically integrates a rocket engine with a high thrust-to-weight ratio and an air-breathing ramjet engine with a high specific impulse in the same flow channel, and is compatible with ejection, subcombustion, and scramjet And pure rocket mode, to achieve high-performance work in wide speed range and large airspace. The intake port is the core component of the RBCC engine. Whether it can be started smoothly according to the design Mach number will determine whether the engine can enter the sub-combustion ramming mode as soon as possible, so as to give full play to the performance advantages of high specific impulse. The biggest difference between the RBCC engine and the conventional ramjet engine in terms of structural and functional feature...

AI Technical Summary

Problems solved by technology

In addition, another important feature of the RBCC engine is that the intake port needs to be started in the ejection mode. At this time, the combustion chamber is in a working state, and there is a high back pressure at the outlet of the intake port, which makes it more difficult to self-start.

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