JP2734849B2 - Ramjet nozzle structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention compresses air flowing in at a flight speed by decelerating the air at an air intake and a diffuser, injects fuel into the air to continuously burn it, and injects hot gas from a nozzle. And more specifically, a so-called IRR (integral rocket), which is accelerated by a booster until the effective operating speed of the ramjet is reached.
The present invention relates to a nozzle structure used in a ramjet type ramjet engine.

[0002]

2. Description of the Related Art Heretofore, there has been a ramjet of the type described above, for example, having a structure as shown in FIG.

That is, a ramjet 100 shown in FIG.
Has a main combustion chamber 102 loaded with a booster propellant 101, an air intake 103 on the outer periphery of the front side of the main combustion chamber 102, a port cover 104 for closing the air intake 103, A port cover release mechanism 105 is provided for releasing the closed state of the port cover 104 at the end of the combustion of the booster propellant 101.

A front end of the main combustion chamber 102 has a sustainer fuel tank 1 filled with a sustainer fuel 106.
07 is provided, and the sustainer fuel 106 is injected from the sustainer fuel injection valve 109 to the air intake 103 via a sustainer fuel flow control mechanism 108, and the port cover of the air intake 103 is provided. An ignition device 110 for a sustainer is provided near 104.

Further, at the rear end of the main combustion chamber 102, a booster nozzle throat 111 for injecting a high-temperature gas generated by the combustion of the booster propellant 101 to the outside rear of the main combustion chamber 102, and a booster nozzle throat 111 A high-temperature gas generated by igniting a mixed gas of the air introduced from the air inlet 103 and the sustainer fuel 106 ejected from the injection valve 109 by the sustainer igniter 110 is located on the outer peripheral side. A ram nozzle throat 112 for injecting rearward is provided concentrically via a clamp band 113, and the booster nozzle throat 111 is provided with a booster ignition device 1
14 is attached.

The clamp band 113 has a groove 113a having a V-shaped cross section, and a booster nozzle throat 111 located inside the ram nozzle throat 112.
Is provided at the rear end of the main combustion chamber 102.
2a.

A ramjet 10 having such a structure
At 0, the booster propellant 101 burns in the main combustion chamber 102 by igniting the booster igniter 114, and this combustion gas is ejected backward from the booster nozzle throat 111 to obtain thrust and start,
Accelerated.

At the end of combustion of the booster propellant 101, the effective operating speed of the ramjet is reached, and a separating mechanism (not shown) provided on the clamp band 113 is operated to release the locked state of the booster nozzle throat 111. , The booster nozzle throat 111 is
Separated from the rear end and released to the outside. At the same time, the port cover 104 of the air inlet 103 is opened by the port cover release mechanism 105, the flow rate is adjusted by the sustainer fuel flow rate control mechanism 108, and the sustainer fuel 106 ejected from the sustainer fuel injection valve 109 and introduced from the air inlet 103. The mixed gas with the air is ignited by a sustainer igniter 110, and this combustion gas is ejected rearward from a ram nozzle throat 112 to obtain a thrust.

That is, in the ramjet 100, the throat diameter of the booster nozzle throat 111 is reduced in order to obtain a high thrust required for the start and acceleration stages. I use them properly.

Incidentally, regarding this type of ramjet,
For example, 655 of “Augmentation Plate Aerospace Engineering Handbook” edited by the Japan Society for Aeronautics and Astronautics issued on April 25, 1983.
Page to page 656 have some explanation.

[0011]

However, in the conventional ramjet 100 having the above-described structure, the booster nozzle throat 111 is mechanically separated from the ram nozzle throat 111 in synchronization with the end of the combustion of the booster propellant 101. The exposed booster nozzle throat 111 is discharged outside the main combustion chamber 102. Therefore, when the booster nozzle throat 111 falls to the ground or the flying object on which the ramjet 100 is mounted is fired from the base unit in the air, the booster nozzle throat 111
In order to avoid the danger that the ramjet 100 will collide with the parent machine or the succeeding aircraft, the location and timing of the launch are restricted, and the design of the combustion time of the booster propellant 101 is restricted. Had been an issue.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems in a conventional IRR type ramjet nozzle, and maintains the desired thrust by maintaining the shape of a booster propellant during combustion. It is an object of the present invention to provide a ramjet nozzle structure provided with a consumable booster nozzle throat which can be exhausted without being discharged to the outside at the end of combustion of the booster propellant.

[0013]

A ramjet nozzle structure according to the present invention is provided at a rear portion of a main combustion chamber and has a high temperature generated by combustion of sustainer fuel and air introduced from outside in the main combustion chamber. A ram nozzle throat for injecting gas rearward, and a booster propellant, which is provided on the inner peripheral side of the ram nozzle throat so as to cover the ram nozzle throat and is charged in the main combustion chamber, by combustion prior to the sustainer fuel. The booster nozzle throat injects the generated high-temperature gas backward.The booster nozzle throat is formed of a consumable material that is consumed by the combustion gas of the booster propellant. The consumption rate of the ram jet is lower than that of the outer circumference. The nozzle configurations are the means for solving the conventional problems described above.

In the ramjet nozzle structure according to the present invention, the booster nozzle throat has sufficient strength to withstand an internal pressure of about 50 to 200 atm generated when the booster propellant is burned, while the booster propellant burns. The gas needs to be burned out for several seconds to several tens of seconds in time with the end of the combustion of the booster propellant, and there are various consumable materials used as the material of the booster nozzle throat that performs such a function. It is considered possible to use a polymer material having a composition, or a mixture of a material for adjusting the consumption rate based on the polymer material.

However, when the booster nozzle throat is formed of a homogeneous consumable material and is burned out at the end of the combustion of the booster propellant, the very early combustion pressure immediately after the ignition of the booster propellant causes the very initial combustion pressure to cause the very early stage. At the stage, most of the nozzles are worn out, and the pressure of the main combustion chamber drops sharply, the thrust drops, and the acceleration performance of the booster is significantly reduced.

Therefore, in the present invention, the booster nozzle throat is formed as a multilayer structure composed of consumable materials having different wear rates or an inclined structure in which the wear rate is gradually changed, and the wear rate is changed in the radial direction, so that the inner circumferential wear is reduced. The speed is lower than the outer circumference, so that the inner peripheral surface of the booster nozzle throat, which has a low consumption rate, withstands the high combustion pressure immediately after the booster propellant ignition, and keeps the initial nozzle throat diameter almost unchanged until the latter stage of combustion At the end of combustion of the booster propellant, where the high thrust at the time of booster operation is maintained and the fast-wearing portion of the outer periphery of the booster nozzle throat is exposed, it is rapidly consumed and disappears at the end of combustion, and disappears at the end of combustion. The throat is exposed and ready for ramjet operation.

In order to produce such a booster nozzle throat, for example, a multilayer structure of two or more polymer materials having different consumption rates can be used.

It is also possible to use an oxidizing agent such as ammonium perchlorate or ammonium nitrate in a binder made of a polymer material, or a mixture obtained by mixing ferric oxide or lithium fluoride as a combustion catalyst as required. it can.

Since this composition is a component system that functions as a solid propellant for a rocket, it exhibits combustion characteristics similar to those of a booster propellant, and it is easy to adjust the consumption rate according to the progress of combustion of the booster propellant. Therefore, it is very convenient as the booster nozzle throat material according to the present invention.

That is, for example, in the case of a component system composed of an epoxy-based binder and ammonium perchlorate, the consumption rate increases as the amount of ammonium perchlorate increases, and the epoxy resin contains 50 to 85 ammonium perchlorate.
By mixing in the range of%, an arbitrary consumption rate can be set. The consumption rate can be increased or decreased by mixing a combustion catalyst such as ferric oxide or lithium fluoride with the mixture, and the adjustable range can be expanded. Note that the lithium fluoride acts as a negative catalyst.

[0021] Accordingly, the inner surface of the booster nozzle throat may have a multi-layered or multi-layered structure in which the amount of ammonium perchlorate in the epoxy resin is reduced, or the epoxy resin containing an appropriate amount of ammonium perchlorate may be burned. The booster nozzle throat according to the present invention can be manufactured by dispersing the ferric oxide, which is a catalyst, such that the content is increased toward the outer surface side.

[0022]

In the ram jet nozzle structure according to the present invention, the booster nozzle throat provided on the inner peripheral side of the ram nozzle throat is formed of a consumable material which is consumed by the combustion gas of the booster propellant, and its consumption is increased. Because the speed is changed in the radial direction and the consumption speed on the inner circumference side is made lower than that on the outer circumference side, the booster nozzle throat has a high combustion pressure immediately after ignition of the booster propellant due to the inner surface side of the booster nozzle throat with a slower consumption speed. At the end of the combustion of the booster propellant, the portion of the outer periphery of the booster nozzle throat where the consumption rate is fast is rapidly consumed and disappears at the end of combustion.

Therefore, the booster nozzle throat is
While the booster propellant is burning, the thrust is maintained to achieve the desired acceleration performance, and when the booster propellant combustion is finished, it completely disappears, exposing the ram nozzle throat without being released outside. This makes the throat diameter suitable for the ramjet.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a ramjet for explaining an embodiment of a ramjet nozzle structure according to the present invention. The ramjet 1 shown in FIG. 1 is loaded with a booster propellant 2. The main combustion chamber 3 includes an air intake 4 on the outer periphery of the front side of the main combustion chamber 3, a port cover 5 for closing the air intake 4, and the end of combustion of the booster propellant 2. And a port cover release mechanism 6 for releasing the closed state by the port cover 5 in a timely manner.

At the front end side of the main combustion chamber 3 is provided a sustainer fuel tank 8 filled with a sustainer fuel 7. The sustainer fuel 7 is supplied from a sustainer fuel injection valve 10 via a sustainer fuel flow control mechanism 9. The fuel is injected into the air intake 4, and a sustainer igniter 11 is provided near the port cover 5 of the air intake 4.

Further, at the rear end of the main combustion chamber 3, the air introduced from the air intake 4 after the end of the combustion of the booster propellant 2 and the sustainer fuel 7 injected from the injection valve 10 are disposed.
A ram nozzle throat 12 for injecting a high-temperature gas generated by igniting the mixed gas with the sustainer ignition device 11 to the outside rear of the main combustion chamber 3,
On the inner peripheral side of the ram nozzle throat 12, a booster nozzle throat 13 for injecting a high-temperature gas generated by the combustion of the booster propellant 2 to the outside rear of the main combustion chamber 3 is provided. A booster ignition device 14 is attached.

The booster nozzle throat 13 has a two-layer structure composed of an epoxy resin and ammonium perchlorate having different mixing ratios, and has an inner peripheral portion composed of 40% epoxy resin and 60% ammonium perchlorate by weight. 1
3a, 30% epoxy resin and 70% ammonium perchlorate
% Of the outer peripheral portion 13b.

The ramjet 1 configured as described above is
First, the booster propellant 2 is burned in the main combustion chamber 3 by igniting the booster igniter 14, and the combustion gas is ejected backward from the booster nozzle throat 13 to obtain a thrust and start, and the ram jet is started. It is accelerated until it reaches the Mach number necessary for the operation of.

At this time, the booster nozzle throat 13
The booster propellant 2 is consumed by being exposed to the combustion gas, but the inner peripheral portion 13a having a low ammonium perchlorate content and a low consumption speed withstands the combustion gas, and is consumed by the combustion of the booster propellant 2. During this time, the original nozzle shape is almost maintained, the nozzle function is sufficiently performed, and the thrust required for acceleration is maintained.

When the Mach number required for the operation of the ramjet is reached and the combustion stage of the booster propellant 2 is approaching, the booster nozzle throat 13 is moved to the inner peripheral portion 1 thereof.
3a is consumed, and the outer peripheral portion 13b, which has a high consumption rate due to a high ammonium perchlorate content, is rapidly consumed, and is rapidly consumed. The nozzle throat 12 is exposed.

When the port cover 5 of the air inlet 4 is opened by the port cover release mechanism 6 in synchronization with the timing, the sustainer fuel 7 whose flow rate is adjusted by the sustainer fuel flow control mechanism 9 is injected into the sustainer fuel. The mixture gas of the gas ejected from the valve 10 and the air introduced from the air inlet 4 is ignited by the igniter 11 for the sustainer, and the combustion gas is ejected rearward from the ram nozzle throat 12 so as to generate a ram jet. Sustaina thrust is obtained.

FIG. 2 is a sectional view of a ramjet for explaining another embodiment of the ramjet nozzle structure according to the present invention. The ramjet 20 shown in FIG.
A booster nozzle throat 21 is provided on the inner peripheral side of the ram nozzle throat 12 in which ferric oxide powder is inclinedly dispersed in an epoxy resin containing 57% of ammonium perchlorate so as to increase toward the outer peripheral side.

Although this embodiment has basically the same operation as the above embodiment, the booster nozzle throat 21 is a functionally graded material whose consumption speed gradually increases as it approaches the outer peripheral side. Therefore, at the same time as maintaining the nozzle shape for a longer period of time, the booster propellant 2 is consumed and disappears more quickly at the end of combustion, resulting in a more remarkable effect.

[0035]

As described above, the ram jet nozzle structure according to the present invention is a ram nozzle nozzle for injecting a high-temperature gas generated by the combustion of the sustainer fuel and the air introduced from the outside in the main combustion chamber. A throat and a high-temperature gas generated by combustion of the booster propellant loaded in the main combustion chamber prior to the sustainer fuel are provided to cover the ram nozzle throat on an inner peripheral side of the ram nozzle throat, and are injected rearward. A booster nozzle throat, wherein the booster nozzle throat is formed of a consumable material that is consumed by a combustion gas of the booster propellant, and the consumption speed is radially changed,
The inner wear side has a lower consumption speed than the outer circumference, so the inner surface of the booster nozzle throat, which has a slower consumption speed, withstands the high combustion pressure immediately after the booster propellant ignition and maintains the original nozzle throat diameter. To prevent a drop in thrust while the booster propellant is burning,
At the end of the booster propellant combustion, the fast-wearing portion on the outer peripheral side of the booster nozzle throat is rapidly consumed and disappears at the end of combustion, so the booster nozzle throat is released outside. Ram nozzle throat can be quickly exposed without
An excellent effect is brought about in that a smooth transition to ramjet operation using sustainer fuel can be achieved.

[Brief description of the drawings]

FIG. 1 is an explanatory longitudinal sectional view of a ramjet showing an embodiment of a ramjet nozzle structure according to the present invention.

FIG. 2 is an explanatory longitudinal sectional view of a ramjet showing another embodiment of a ramjet nozzle structure according to the present invention.

FIG. 3 is an explanatory longitudinal sectional view of a conventional ramjet.

[Explanation of symbols]

 1,20 ram jet 2 booster propellant 3 main combustion chamber 7 sustainer fuel 12 ram nozzle throat 13,21 booster nozzle throat

Claims (6)

(57) [Claims] 1. A ram nozzle throat provided at a rear portion of a main combustion chamber for injecting rearward hot gas generated by combustion of a sustainer fuel and air introduced from outside in the main combustion chamber, and a ram nozzle throat. A booster nozzle throat which is provided to cover the ram nozzle throat on the inner peripheral side of the booster propellant charged in the main combustion chamber, and injects a hot gas generated by combustion prior to the sustainer fuel backward. The booster nozzle throat is formed of a consumable material that is consumed by the combustion gas of the booster propellant, and the consumption speed is changed in the radial direction, so that the consumption speed on the inner peripheral side is made slower than that on the outer peripheral side. Ramjet nozzle structure. 2. The booster nozzle throat is formed by laminating a plurality of consumable materials having different consumption speeds in a radial direction, and an inner peripheral layer includes a booster propellant whose combustion is completed.
Consumable before sintering is composed of consumable material of the consumable speed that can complete it outermost peripheral layer combustion complete substantially simultaneously depleted in the booster propellant is composed of a consumable material of the consumable speed that can complete The ram jet nozzle structure according to claim 1, wherein: 3. The ramjet nozzle structure according to claim 1, wherein said consumable material is a solid propellant comprising a polymer material and an oxidizing agent. 4. The ramjet nozzle structure according to claim 1, wherein the consumable material is a solid propellant comprising a polymer material, an oxidizing agent, and a combustion catalyst. 5. The booster nozzle throat has a multilayer structure of a solid propellant comprising a polymer material and an oxidant, and a solid propellant comprising a polymer material, an oxidant and a combustion catalyst. 2. The nozzle structure of the ramjet according to 1. 6. A ramjet nozzle structure according to claim 1, wherein said booster nozzle throat is obtained by dispersing a combustion catalyst in a solid propellant comprising a polymer material and an oxidant.