CN112664350A

CN112664350A - Multi-stage charging solid fuel ramjet engine

Info

Publication number: CN112664350A
Application number: CN202011482656.3A
Authority: CN
Inventors: 高鲲鹏; 李海波; 常煜辉
Original assignee: Beijing Power Machinery Institute
Current assignee: Beijing Power Machinery Institute
Priority date: 2020-12-15
Filing date: 2020-12-15
Publication date: 2021-04-16

Abstract

The invention provides a multi-stage charge solid fuel ramjet engine, which provides a multi-stage charge solid fuel ramjet engine, and simultaneously, through multi-stage charge performance matching, different parameters such as geometric dimension, burning speed and the like are selected for each stage of charge, so that the problem of poor matching of the engine performance with the flying height and the flying speed is solved, the self-adaptive work of the solid fuel ramjet engine in a large airspace and a wide speed is realized, the engine performance is greatly improved, the use condition of the engine is widened, and a feasible technical approach is provided for the future ultra-long range ram extended-range cannonball.

Description

Multi-stage charging solid fuel ramjet engine

Technical Field

The invention belongs to the technical field of solid fuel ramjet engines, and particularly relates to a multi-stage charge solid fuel ramjet engine.

Background

A solid fuel ramjet (SFRJ for short) is a ramjet in which the incoming air directly reacts with the solid charge poured against the wall to form primary fuel gas, and the primary fuel gas is afterburned in an afterburning chamber. The SFRJ has the advantages of high specific impulse, high reliability, low cost, certain performance self-adjusting capability and the like, and has good application prospect in the range extension of the cannonball.

As shown in figure 1, after the cannonball is taken out of the chamber, the ramjet engine works in relay mode until the cannonball rises to the high altitude, and the work of the engine is finished. The working height range of the shot solid fuel ramjet engine is 0 km-10 km, and the working speed range is Ma2.2-Ma3.5. As the cannonball climbs, the height and the speed of the engine are increased and reduced, and the air flow captured by the engine is reduced; meanwhile, the combustion surface of the solid propellant in the charge combustion chamber is increased, the gas flow is increased, the margin of an air inlet channel of the engine is reduced sharply, and the risk that the air inlet channel does not start exists in the engine. In order to ensure that the engine works reliably at high altitude, the throat diameter of an engine nozzle needs to be enlarged, which can cause that the air inlet passage margin is higher and the engine performance is poorer when the engine works at low altitude, so that the high-low altitude margin and the performance of the engine are difficult to match.

When the gun-injection solid fuel ramjet engine works in a large airspace and a wide speed range, the self-adaptive change of gas flow, engine margin and engine thrust along with height and speed is required, and the high-performance and high-margin work of the engine is realized. The engine adopting single type charging has single change rule of parameters such as gas flow, engine margin, engine thrust and the like, the matching of the engine performance, the flying height and the flying speed is poor, and the contradiction exists between high performance and high margin.

Disclosure of Invention

In order to solve the problems, the invention provides a multi-stage charge solid fuel ramjet engine, which utilizes the difference of burning speed, pressure index, heat value and density of different charge types in the gun-injection solid fuel ramjet engine, and meets the requirements of self-adaptive change of gas flow, engine margin and engine thrust along with height and speed when the gun-injection solid fuel ramjet engine works in a large airspace and a wide speed range by a preferable combination strategy.

The utility model provides a multistage powder charge solid fuel ramjet, includes intake duct 1, powder charge combustion chamber 2, afterburning room 3 and

spray tube

4, 2 adherence pouring of powder charge combustion chamber have more than the more than two-stage powder charge of cascading each other on powder charge combustion chamber axial direction, wherein, the burning rate, geometric dimensions, pressure index, calorific value, density and the type of a medicine of powder charge at all levels are not identical.

Further, the burning rate, the pressure index, the heat value, the density and the drug type of each stage of charge are determined according to the set overall index of the cannonball.

Furthermore, two-stage charges which are mutually cascaded are poured in the charging combustion chamber in an adherence manner.

Has the advantages that:

the invention provides a multi-stage charge solid fuel ramjet engine, which provides a multi-stage charge solid fuel ramjet engine, and simultaneously selects different parameters such as geometric dimension, burning speed and the like for each stage of charge through multi-stage charge performance matching, solves the problem of poor matching of the engine performance with the flying height and the flying speed, realizes self-adaptive work in a large airspace and a wide speed area of the solid fuel ramjet engine, greatly improves the engine performance, widens the engine use condition, and provides a feasible technical approach for a future ultra-long range ram stroke-increasing cannonball.

Drawings

Fig. 1 is a schematic structural diagram of a conventional gun-fired solid fuel pressure engine;

FIG. 2 is a schematic structural diagram of a multi-charge solid fuel ramjet engine provided by the invention;

FIG. 3 is a schematic representation of thrust versus engine operating time for a two-charge and single-charge solid fuel ramjet engine provided by the present invention;

FIG. 4 is a graphical representation of the residual air coefficient of a two-charge and single-charge solid fuel ramjet engine provided by the present invention as a function of engine operating time;

FIG. 5 is a graphical representation of the residual air coefficient of a two-charge and single-charge solid fuel ramjet engine provided by the present invention as a function of engine operating time;

FIG. 6 is a schematic representation of engine margin as a function of engine operating time for a two-charge and single-charge solid fuel ramjet engine provided in accordance with the present invention;

1-air inlet pipe, 2-charge combustion chamber, 3-afterburning chamber, 4-nozzle, 5-charge, 6-first-stage charge, 7-second-stage charge, 8-center cone, 9-charge column and 10-outer cover shell.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the following description is provided for a clear and complete description of the technical solutions of the embodiments of the present application with reference to the drawings in the embodiments of the present application.

Referring to fig. 2, the figure is a schematic diagram of the structure of a multi-charge solid fuel ramjet engine provided by the invention. The utility model provides a multistage powder charge solid fuel ramjet, includes intake duct 1, powder charge combustion chamber 2, afterburning room 3 and

spray tube

4, 2 adherence pouring of powder charge combustion chamber have in its axial direction cascaded two-stage powder charge 5 each other, wherein, the burning rate, geometric dimensions, pressure index, hot value, density and the type of a medicine of first order powder charge 6 and second level powder charge 7 are not identical, can carry out powder charge performance and structural design optimization according to the general index requirement of shell, select suitable powder charge.

It can be seen that the thrust, the residual air coefficient (air flow/theoretical air/charge gas flow), and the engine margin of the two-charge and single-charge solid fuel ramjet engines vary with engine operating time as shown in fig. 3-5. As can be seen from fig. 3 to 5, the two-stage charge solid fuel ramjet engine has the following advantages under the matching of different charging performances: the engine has longer working time and can provide longer thrust; the thrust variation range is smaller and is stabilized within a certain interval; the regulating effect of the charge gas flow is strong, and the residual gas coefficient is stabilized at 1-3; and fourthly, the margin fluctuation of the engine is smaller, and the high-reliability and high-performance work can be realized.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it should be understood that various changes and modifications can be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. The utility model provides a multistage powder charge solid fuel ramjet, includes intake duct (1), powder charge combustion chamber (2), afterburning room (3) and spray tube (4), its characterized in that, powder charge combustion chamber (2) adherence pouring has the more than two-stage powder charge that cascades each other on powder charge combustion chamber axial direction, wherein, the burning rate, geometric dimension, pressure index, calorific value, density and the type of a medicine of each grade powder charge are not identical.

2. A multi-charge solid fuel ramjet as claimed in claim 1, wherein the combustion rate, pressure index, calorific value, density and shape of each charge are determined in accordance with set general indicators of the projectile.

3. The multi-charge solid fuel ramjet according to claim 1, wherein said charge combustion chamber is wall-mounted with two-stage charges in cascade.

4. A multi-charge solid fuel ramjet according to claim 3, wherein the two-charge burn rate, geometry, pressure index, calorific value, density and shape are not all the same.

5. The multi-charge solid fuel ramjet of claim 1, wherein the operation time is longer, the thrust variation range is smaller, and the margin fluctuation is smaller.