JPH03130564A - Rocket motor - Google Patents

Abstract

PURPOSE:To prevent generation of erosive burning by arranging an injection nozzle, which injects combustion gas generated in a combustion chamber toward the rear, in the intermediate part periphery of a rocket motor main unit in a position where a generated amount of combustion gas is almost equal in both front and rear side combustion parts. CONSTITUTION:A rocket main unit 1 is formed of both front and rear cylinder units 2, 3 and an annular nozzle mounting member 4 for connecting these cylinder units. While the lower from the intermediate part of the rocket main unit 1, that is, the rear from a rear end part of the front part cylinder unit 2 is floating-fitted into an outer cylinder 10. Further a secondary combustion chamber 13 is formed between the rocket main unit 1 and the outer cylinder 10. Here in the periphery of the intermediate part, which is in the point end part of the secondary combustion chamber 13, in the rocket main unit 1, a plurality of injection nozzles 14 for injecting combustible gas are arranged in the peripheral direction with an equal pitch. Each injection nozzle 14 is arranged in a position where combustible gas, generated in a plurality of combustion chambers 7, 8 set so as to almost equalize a generated combustible gas amount, is simultaneously jetted.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rocket having a combustion chamber in which a propellant is loaded within the rocket body.

(Prior art) As shown in FIG. 4, a conventional rocket has an internal combustion type cylindrical solid fuel (#91 propellant) inside the rocket body 51.
52 is loaded, and a combustion chamber 53 is formed inside the cylinder. An injection nozzle 54 is provided at the rear of the rocket body 1, and this injection nozzle 54 injects high-temperature, high-pressure combustion gas backward that is not generated in the combustion chamber 53. An igniter 55 for igniting the solid fuel 52 is provided at the tip of the combustion chamber 53 (for example, Japanese Patent Laid-Open No. 59-128
No. 955 discloses something similar).

When the solid fuel 52 is ignited by the igniter 55, the solid fuel 52 burns from its inner peripheral surface to generate high temperature and high pressure combustion gas, which is injected from the injection nozzle 54.

(Problem M to be Solved by the Invention) By the way, the combustion gas generated at the tip of the combustion chamber 53 flows from the tip side to the rear end and is injected from the injection nozzle 54. Further, since the solid fuel 52 is burned over the entire inner circumferential surface 52a, the flow velocity of the combustion gas increases toward the rear. For this reason, erosive combustion occurs on the rear side of the solid fuel 52, making it impossible to obtain a constant thrust for a long time. Further, due to the erosive combustion, pressure changes occur in the combustion chamber, causing vibrations, which causes problems such as applying a vibration load to mounted electronic equipment and the like.

(Objective) The present invention has been made in view of the above-mentioned problems, and its object is to provide a rocket that can prevent the occurrence of erosive combustion.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a rocket motor body in which internal combustion type propellant is loaded to form a combustion chamber, and a rocket motor body in which the combustion chamber is formed. In a rocket motor provided with an injection nozzle that injects combustion gas generated in a chamber toward the rear, the injection nozzle is located on the outer periphery of an intermediate portion of the rocket motor body, and is connected to the front side combustion part and the rear side combustion part. It is characterized in that it is provided at a position where the amount of combustion gas generated is approximately equal.

(Function) Since the present invention has the above configuration, the combustion gases generated at the front side and the rear side of the combustion chamber flow to the middle part of the combustion chamber where the injection nozzle is provided, and collide with each other. So,
The flow velocity of combustion gas becomes smaller.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIGS. 1 and 1112 are cross-sectional views showing an air introduction type rocket as an example of the structure of a rocket according to the present invention, and in the figures, 1 is a rocket body having a hollow interior. This rocket body 1 includes a front cylinder 2 and a rear cylinder 3.
and an annular nozzle attachment member 4 that connects the cylindrical bodies 2.3 to each other.

A cylindrical solid fuel (propellant) 5, 6 is loaded into each cylinder 2, 3, and a primary combustion chamber (front side combustion part) 7. (Rear side combustion part) 8 is formed. Further, an igniter 9 is attached to the tip of the front cylinder 2. Moreover, the rear cylinder 3 includes, in order from the top (in FIG. 4): a first tapered part 3a, a parallel part 3b, a second tapered part 3c, and a spike nozzle part 3.
It has d. Incidentally, each of the tapered portions 3a, 3c is set so that its diameter gradually decreases toward the rear.

The lower part of the rocket main body l, that is, the rear part of the front cylinder 2 from the rear end, is loosely fitted into the outer cylinder 1 (l. The distal end and the rear end are connected to the stay 11.
．． It is connected and fixed to the rocket body l at 12. A secondary combustion chamber 13 is formed between the rocket body 1 and the outer cylinder 1 (1).

A plurality of injection nozzles 14 for injecting combustible gas are provided at equal pitches in the circumferential direction on the outer periphery of the intermediate portion of the rocket body l, which is inside the tip of the secondary combustion chamber 13. The position where the injection nozzle 14 is provided is the position where the combustible gas generated in the combustion chamber 7 and the combustion chamber 8 is simultaneously jetted out, and
The combustion chambers 7.8 are set so that the inner surfaces of both propellants 5, 6 have the same surface area, so that the amount of combustible gas generated in each combustion chamber 7.8 is approximately equal.

On the other hand, the secondary combustion chamber 13 is located at the J! of the first tapered portion 3a of the rear cylinder body 3. A supersonic mixing and combustion section 21 formed around the radius R, and a subsonic mixing and combustion section 22 formed around the parallel section 3b.
and the opening 23 formed around the second tapered portion 3c.

The injection nozzle 14 is configured to inject rearward the high-temperature, high-pressure combustible gas generated in the primary combustion chambers 7 and 8, and this combustible gas expands at the opening 23 of the secondary combustion chamber 13 and is injected. This makes it possible to obtain a predetermined propulsive force even before air is introduced into the secondary combustion chamber 13.

In the supersonic mixing and combustion section 21 of the secondary combustion chamber 13, by providing the first tapered section 3a whose diameter decreases toward the rear, the air maintains a supersonic state and the backflow of air from the air inlet 24 is prevented. air can be taken in well,
The injection nozzle 14 also mixes and burns the injected combustion gas.

The subsonic mixing and combustion section 22 is designed to reduce the speed of air to subsonic speed and increase the efficiency of combustion with combustion gas.

In the opening 23, the air and combustion gas combusted in the subsonic mixing combustion section 22 are expanded and injected through the spike nozzle 3d.

By the way, since the spike nozzle 3d protrudes from the rear end of the outer cylinder 3, even when the expansion rate of the combustion gas is large in the atmosphere and the atmospheric pressure is higher than the combustion gas pressure,
The combustion gas is pressed against the spike nozzle 3D wall by being compressed from the surroundings, and separation phenomenon does not occur as with cone nozzles. Therefore, the specified propulsion force is secured not only outside the atmosphere but also under atmospheric pressure, which will be described later. can do.

Outside the atmosphere, air is not introduced into the secondary combustion chamber 13, but just as immediately after launch, combustion gas is directly injected from the plurality of injection nozzles 14 to obtain a predetermined thrust. can.

Furthermore, since this rocket has a secondary combustion chamber 13 formed on the outer periphery of the rocket body 1, there is no need to provide a secondary combustion chamber within the rocket body, and the overall length can be shortened.

N is a payload section on which electronic components and the like are mounted at the tip of the front cylinder 2.

Now, when solid fuel 5.6 is ignited with igniter 9,
The entire inner circumferential surface of the solid fuel 5.6 is combusted to generate high-temperature, high-pressure combustible gas. The combustible gas generated in the combustion chamber 7 flows in the direction of arrow P and is also injected through the injection nozzle 14.

On the other hand, combustible gas generated in the combustion chamber 8 flows in the direction of arrow Q and is simultaneously injected from the injection nozzle 14.

By the way, since the propellants 5 and 6 are designed to have the same inner surface area, the amount of combustible gas generated in the combustion chamber 7 and the amount of combustible gas generated in the combustion chamber 8 are approximately equal. The flow velocity of the combustible gas becomes small between the combustion chamber 7 and the combustion chamber 8 in the vicinity where the two combustible gases collide, as shown by the solid line in FIG. 3.

Further, although the flow velocity reaches its maximum in the middle of each combustion chamber 7, 8, the maximum flow velocity is considerably smaller than the conventional flow velocity (2), and the occurrence of erosive combustion of the solid fuel 5.6 is prevented. Therefore, a constant thrust can be maintained for a long time, and since pressure changes do not occur in the combustion chambers 7 and 8 due to erosive combustion, vibrations caused by pressure changes will not cause vibration loads to be applied to the mounted electronic equipment, etc. do not have.

In the above embodiments, an air introduction type rocket has been described, but it goes without saying that other rockets without an outer cylinder may be used.

(Effects) As explained above, according to the present invention, erosion and combustion of the propellant can be prevented, and a constant thrust can be maintained for a long time. Further, since no pressure change occurs in the combustion chamber due to erosive combustion, no vibration load is applied to the mounted electronic equipment.

[Brief explanation of the drawing]

Figure 1 is a partial sectional view showing the structure of the rocket related to this invention, Figure 2 is a sectional view showing the structure of the rocket, and Figure 3 is the relationship between the position of the combustion chamber and the flow velocity of combustion gas. Explanatory diagram, FIG. 4 is an explanatory diagram of a conventional rocket. 1...Rocket body 5.8...Solid fuel (propellant) 7...-Next combustion chamber (front side combustion part) 8...-Next combustion chamber (rear side combustion part) 14...・Injection nozzle

Claims (1)

[Scope of Claims] An internal combustion type propellant is loaded into a rocket motor body to form a combustion chamber, and combustion gas generated in the combustion chamber is injected rearward into the rocket motor body. In the rocket motor provided with a nozzle, the injection nozzle is provided at a position on the outer periphery of an intermediate portion of the rocket motor body at a position where the amount of combustion gas generated by the front side combustion section and the rear side combustion section is approximately equal. A rocket motor featuring