JP3717002B2 - Solid rocket engine - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a solid rocket engine (also referred to as a solid rocket motor) that obtains a flight thrust by injecting combustion gas generated by combustion of a solid propellant loaded in a combustion chamber from a nozzle.
[0002]
[Prior art]
Conventionally, as such a solid rocket engine, for example, one shown in FIG. 4 is provided, and this solid rocket engine 51 includes a combustion chamber 53 loaded with a solid propellant 52.
[0003]
A solid propellant igniter 54 is provided at the center of the front end of the combustion chamber 53, while a nozzle 55 is provided at the rear end of the combustion chamber 53. The solid propellant 52 is a mixture of resin, metal and oxidant. It has become.
[0004]
The solid rocket engine 51 burns the solid propellant 52 in the combustion chamber 53 by ignition by the solid propellant igniter 54 and obtains thrust by injecting the combustion gas generated thereby from the nozzle 55. .
[0005]
The solid rocket engine having such a structure is described, for example, in “Rocket Engineering” by Ichiro Kimura, January 27, 1993, pages 462 to 463 issued by Yokendo Co., Ltd.
[0006]
[Problems to be solved by the invention]
However, the conventional solid rocket engine 51 described above burns and flies the solid propellant 52 from the lower atmosphere to the upper atmosphere or the outer space where the air is thin, that is, the solid propellant 52 resin and Since the metal burns with its own oxidant and flies, there is a problem that the propulsion performance cannot be said to be good in the lower atmosphere because the surrounding air cannot be used as an oxidant. It has been a conventional problem to be solved.
[0007]
OBJECT OF THE INVENTION
The present invention has been made paying attention to the above-described conventional problems, and is capable of efficient propulsion according to the flying environment from the low atmosphere to the high atmosphere or the outer space where air is rare. It aims to provide a rocket engine.
[0008]
[Means for Solving the Problems]
The invention according to claim 1 of the present invention is a solid rocket engine comprising a combustion chamber loaded with a solid propellant and a nozzle for injecting a combustion gas generated by combustion of the solid propellant in the combustion chamber. A gas generator for starting the supply of excess fuel combustion gas to the combustion chamber from the end of the combustion of the medicine and an oxidant supply device for starting the supply of oxidant to the combustion chamber as the air density decreases externally; The combustion chamber is provided with an air intake opening that is opened at the end of combustion of the solid propellant and closed as the air density decreases outside, and the ramjet that detachably supports the nozzle at the end of combustion of the solid propellant It is characterized by having a configuration provided with a nozzle, and means for solving the above-described conventional problems in the configuration of such a solid rocket engine To have.
[0009]
Further, in the solid rocket engine according to claim 2 of the present invention, the gas generating device injects the solid fuel, the solid fuel igniter, and the excess fuel combustion gas generated by the combustion of the solid fuel into the combustion chamber. For example, a composite propellant or azide polymer containing some oxidizer is used as the solid fuel.
[0010]
Furthermore, in the solid rocket engine according to claim 3 of the present invention, the oxidizer supply device includes a liquid oxidizer filled in a tank, a piston that is operated by a combustion pressure of a gas generator, and a liquid oxidizer that is pressed against the piston. In the solid rocket engine according to claim 4 of the present invention, the oxidizer supply device is provided with a valve for controlling the operation of the piston. In this case, for example, NTO (dinitrogen tetroxide), dinitrogen monoxide, nitric acid, or hydrogen peroxide is used as the liquid oxidizing agent.
[0011]
Furthermore, in the solid rocket engine according to claim 5 of the present invention, the air intake is configured to be opened and closed by an intake opening / closing mechanism including an actuator and a port cover that is rotated by the operation of the actuator. The solid rocket engine according to claim 6 includes an external air density detecting means.
[0012]
[Effects of the Invention]
In the solid rocket engine according to claims 1 and 2 of the present invention, first, solid propellant is ignited and burned, and combustion gas is injected from the nozzle to perform initial acceleration.
[0013]
Next, at the stage where the solid propellant is at the end of combustion, the nozzle is separated from the ramjet nozzle and the air intake is opened. At the same time, the gas generator is activated to remove excess fuel from the combustion chamber. The supply is started, the external air introduced from the air intake port and compressed by the ram pressure and the combustion gas with excess fuel are mixed and combusted in the combustion chamber, and the resulting combustion gas is injected from the ramjet nozzle. The ramjet is activated.
[0014]
Then, at the stage where the outside air density is reduced, the air intake is closed and the oxidant supply device is operated to start the supply of the oxidant to the combustion chamber. The excess fuel combustion gas supplied from the gas generator And the oxidant are mixed and burned in the combustion chamber, and the combustion gas is injected from the ramjet nozzle to enter the gas hybrid rocket operating state.
[0015]
Therefore, in this solid rocket engine, initial acceleration is performed by combustion of solid propellant, flying from the lower atmosphere to the upper atmosphere where the air is dilute by ramjet operation, and in the space by the gas hybrid rocket operation Therefore, efficient propulsion according to the flight environment is realized from the lower atmosphere to outer space. In addition, since the gas generator supplies excessive fuel combustion gas in both the ramjet operating state and the gas hybrid rocket operating state, it is not necessary to provide a gas generator for each state. The weight will be reduced by that amount.
[0016]
Since the solid rocket engine according to claim 3 of the present invention has the above-described configuration, the liquid oxidant can be easily supplied to the combustion chamber without separately providing a device for pressurizing the inside of the tank. In the solid rocket engine according to the fourth aspect of the present invention, thrust control during the operation of the gas hybrid rocket in space can be easily performed.
[0017]
In the solid rocket engine according to the fifth aspect of the present invention, the air intake is opened and closed easily and reliably. In the solid rocket engine according to the sixth aspect of the present invention, when the external air density decreases. That is, when the effective operating altitude and speed of the ramjet reach the limits, the ramjet operating state is quickly shifted to the gas hybrid rocket operating state, thereby realizing more efficient propulsion.
[0018]
【Example】
1 to 3 show an embodiment of a solid rocket engine according to the present invention.
[0019]
As shown in FIG. 1, the solid rocket engine 1 has a combustion chamber 3 loaded with a booster propellant 2. A front end side of the combustion chamber 3 is connected to a port 3 a provided in the combustion chamber 3. The air intakes 4 communicating with the inside are arranged at a plurality of locations in the circumferential direction. One set of the air intake opening / closing mechanism 5 provided with the actuator 5a and the port cover 5b is disposed at a place where the air intake 4 is provided. The air intake opening / closing mechanism 5 operates the actuator 5a. By rotating the port cover 5b, the port 3a is closed and opened.
[0020]
On the other hand, a booster nozzle 7 and a ramjet nozzle 8 having a booster propellant ignition device 6 detachably mounted at the center are provided concentrically at the rear end of the combustion chamber 3. A booster nozzle 7 is detachably supported via a separation joint 9 that is interlocked with the operation of the intake opening / closing mechanism 5.
[0021]
In this case, as shown in FIG. 2, the air intake opening / closing mechanism 5 operates at the stage where the booster propellant 2 reaches the end of combustion, and separates the booster nozzle 7 from the ramjet nozzle 8 and the air intake 4. The air intake 4 is controlled so as to be reactivated and closed as the air density decreases outside.
[0022]
In addition, the solid rocket engine 1 includes a gas generator 10 in front of the combustion chamber 3. The gas generator 10 includes a solid fuel 12 loaded in a case 11 and a solid fuel igniter 13. And a nozzle 14 for injecting an excess fuel combustion gas generated by the combustion of the solid fuel 12 into the combustion chamber 3.
[0023]
The gas generator 10 starts supplying excess combustion gas to the combustion chamber 3 at the stage when the booster propellant 2 reaches the end of combustion, and is introduced from the combustion gas and the air intake 4 to the ram pressure. The solid rocket engine 1 is made to perform a ramjet operation by mixing and burning external air compressed by the above.
[0024]
The solid rocket engine 1 further includes an oxidant supply device 20. The oxidant supply device 20 includes a liquid oxidant 22 filled in a tank 21 located in front of the case 11 of the gas generator 10 and a tube provided in the tank 21 and communicating with the case 11 of the gas generator 10. And a piston 24 that is operated by the combustion pressure in the case 11 introduced through the passage 23, and an injector 26 that is provided integrally with the front end partition wall 3 b of the combustion chamber 3 and communicates with the tank 21 through the pressure feed tube 25. In addition, a valve 27 for controlling the operation of the piston 24 is provided in a portion of the pressure feeding tube 25 near the injector 26.
[0025]
As shown in FIG. 3, the oxidant supply device 20 opens the valve 27 when the outside air density decreases, and thereby burns in the case 11 introduced into the tank 21 through the tube 23. The piston 24 is actuated by pressure, and the liquid oxidant 22 pressed by the piston 24 is injected from the injector 26 into the combustion chamber 3 to cause the solid rocket engine 1 to perform the gas hybrid rocket operation. Yes.
[0026]
Furthermore, this solid rocket engine 1 is provided with a pitot tube 30 as an external air density detection means in a portion near the head, detects the external air density from the air speed, and from the ramjet operating state. The gas hybrid rocket is in a state of being promptly shifted to the operating state.
[0027]
In the solid rocket engine 1 having such a structure, first, the booster propellant 2 is ignited by the booster propellant ignition device 6, and the combustion gas generated by the combustion of the booster propellant 2 in the combustion chamber 3 is ignited. It starts and accelerates by injecting from the booster nozzle 7 from which 6 is removed.
[0028]
Subsequently, at the end of combustion of the booster propellant 2, as shown in FIG. 2, the booster nozzle 7 is separated at the separation joint 9 by the operation of the air intake opening / closing mechanism 5, and the port cover 5b is rotated at the same time. Then, the port 3a is opened, and in the gas generator 10, the solid fuel 12 is ignited by the solid fuel igniter 13, and the excess fuel combustion gas generated by the combustion of the solid fuel 12 is discharged from the nozzle 14. It is injected into the combustion chamber 3.
[0029]
Next, the injected excess fuel combustion gas and the air introduced from the air intake 4 and compressed by the ram pressure are mixed and combusted in the combustion chamber 3, and the combustion gas generated thereby is injected from the ramjet nozzle 8. The ramjet is activated.
[0030]
When the Pitot tube 30 detects a decrease in the outside air density when the air reaches a lean high-rise region, the air intake opening / closing mechanism 5 is reactivated to open the air intake 4 as shown in FIG. At the same time, the valve 27 is opened in the oxidant supply device 20, whereby the piston 24 moves in the right direction in the figure due to the combustion pressure in the case 11 introduced into the tank 21 through the tube 23, The liquid oxidant 22 pressed by the piston 24 is injected from the injector 26 into the combustion chamber 3.
[0031]
Subsequently, in the combustion chamber 3, the liquid oxidant 22 and the excess fuel combustion gas supplied from the gas generator 10 are mixed and burned, and the resulting combustion gas is injected from the ramjet nozzle 8 to form a gas hybrid. The rocket is activated.
[0032]
At this time, if the opening degree of the valve 27 in the oxidant supply device 20 is adjusted, thrust control can be easily performed.
[0033]
Therefore, in this solid rocket engine 1, initial acceleration is performed by the combustion of the booster propellant 2 and the rocket is operated by ramjet operation from the lower atmosphere to the upper atmosphere where the air is dilute. Therefore, efficient propulsion according to the flight environment can be realized from the lower atmosphere to the outer space.
[0034]
In addition, since the gas generator 10 constantly supplies excess fuel combustion gas in each of the ramjet operating state and the gas hybrid rocket operating state, there is no need to provide the gas generating device 10 in each state individually. The weight will be reduced accordingly.
[0035]
Further, in the solid rocket engine 1 in this embodiment, the effective operating altitude and speed of the ramjet has reached the limit because the pitot tube 30 as the external air density detecting means is provided in the portion near the head. Sometimes, the ramjet operation state is quickly shifted to the gas hybrid rocket operation state, and further efficient propulsion is realized.
[0036]
The detailed configuration of the solid rocket engine according to the present invention is not limited to the above-described embodiment.
[0037]
【The invention's effect】
As described above, since the solid rocket engine according to claims 1 and 2 of the present invention has the above-described configuration, the initial acceleration is performed by the combustion of the solid propellant, and the upper atmosphere where the air is lean from the lower atmosphere. Because it can fly to the inside by ramjet operation and can navigate by a gas hybrid rocket operation in outer space, efficient propulsion according to the flying environment is possible from low atmosphere to outer space In addition, since the gas generator is used in both the ramjet operation state and the gas hybrid rocket operation state, it is not necessary to provide a gas generator for each state. As a result, it is possible to achieve an extremely excellent effect that weight can be reduced.
[0038]
Further, since the solid rocket engine according to claim 3 of the present invention has the above-described configuration, it is possible to easily supply the liquid oxidant to the combustion chamber without separately providing a device for pressurizing the inside of the tank. In the solid rocket engine according to claim 4 of the present invention, it is possible to achieve a remarkably excellent effect that it is possible to easily perform thrust control when operating the gas hybrid rocket in outer space.
[0039]
Furthermore, since the solid rocket engine according to claim 5 of the present invention has the above-described configuration, the air intake can be easily and reliably opened and closed. In the solid rocket engine according to claim 6 of the present invention, When the effective operating altitude and speed in the ramjet operating state reach the limit, it is possible to make a quick transition to the gas hybrid rocket operating state, which has the remarkable effect that more efficient propulsion can be realized. Brought about.
[Brief description of the drawings]
FIG. 1 is a cross-sectional explanatory view before operation showing an embodiment of a solid rocket engine according to the present invention.
2 is a cross-sectional explanatory view showing a ramjet operating state of the solid rocket engine in FIG. 1. FIG.
FIG. 3 is a cross-sectional explanatory view showing a gas hybrid operation state of the solid rocket engine in FIG. 1;
FIG. 4 is a cross-sectional explanatory view of a conventional solid rocket engine.
[Explanation of symbols]
1 Solid rocket engine 2 Booster propellant (solid propellant)
3 Combustion chamber 4 Air intake 5 Air intake opening / closing mechanism 5a Actuator (Air intake opening / closing mechanism)
5b Port cover (Air intake opening / closing mechanism)
7 Booster nozzle (nozzle)
8 Ramjet nozzle 10 Gas generator 12 Solid fuel (gas generator)
13 Solid fuel igniter (gas generator)
14 Nozzle (gas generator)
20 Oxidant supply device 21 Tank (Oxidant supply device)
22 Liquid oxidizer (oxidizer supply device)
24 piston (oxidizer supply device)
26 Injector (oxidizer supply device)
27 Valve (oxidizer supply device)
30 Pitot tube (external air density detection means)

Claims (6)

In a solid rocket engine having a combustion chamber loaded with a solid propellant and a nozzle for injecting combustion gas generated by the combustion of the solid propellant in the combustion chamber, fuel from the end of combustion of the solid propellant to the combustion chamber A gas generator for starting supply of excess combustion gas and an oxidant supply device for starting supply of oxidant to the combustion chamber as the outside air density decreases are provided, and the combustion chamber contains the solid propellant. A solid rocket characterized in that an air intake opening that is opened at the end of combustion and closed as the air density decreases outside is provided, and a ramjet nozzle is provided that detachably supports the nozzle at the end of combustion of the solid propellant. engine. 2. The solid rocket according to claim 1, wherein the gas generator includes a solid fuel, a solid fuel igniter, and a nozzle that injects an excessive fuel combustion gas generated by the combustion of the solid fuel into a combustion chamber. engine. The oxidant supply device includes a liquid oxidant filled in a tank, a piston that is operated by a combustion pressure of a gas generator, and an injector that injects the liquid oxidant pressed by the piston into a combustion chamber. Item 3. The solid rocket engine according to Item 1 or 2. The solid rocket engine according to claim 3, wherein the oxidant supply device includes a valve for controlling the operation of the piston. The solid rocket engine according to any one of claims 1 to 4, wherein the air intake is opened and closed by an intake opening / closing mechanism including an actuator and a port cover that is rotated by the operation of the actuator. The solid rocket engine according to any one of claims 1 to 5, further comprising an external air density detecting means.

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