阅读说明：本技术 高压燃烧器实验系统及可视化高压燃烧器 (High-pressure combustor experimental system and visual high-pressure combustor ) 是由 沙本尚 那旭东 夏智勋 颜小婷 马立坤 冯运超 李洋 于 2021-02-04 设计创作，主要内容包括：一种高压燃烧器实验系统及可视化高压燃烧器,包括测控系统,可视化高压燃烧器,高速成像系统,激光点火系统以及高压气源与管路。可视化高压燃烧器采用自下而上的环形进气的方式,可以对视场内烟雾进行吹除,有效降低了推进剂燃烧烟雾的影响。同时可视化高压燃烧器上部设置与燃烧腔一体化贯通的稳压腔,通过竖直方向扩大燃烧腔容积可实现燃烧过程中的稳压,可以对烟雾有疏散作用,减小烟雾影响。实验时,手动调节可视化高压燃烧器顶部的排气阀可使进排气平衡从而及时排除烟雾。本发明的可视化高压燃烧器的底座采用铝合金旋式底座,可快速更换药条,大大提高了实验效率。(The utility model provides a high pressure combustor experimental system and visual high pressure combustor, is including observing and controling the system, visual high pressure combustor, high-speed imaging system, laser ignition system and high-pressure gas source and pipeline. The visual high-pressure combustor adopts the mode that annular was admitted air from bottom to top, can blow off smog in the visual field, has effectively reduced the influence of propellant burning smog. Meanwhile, the upper part of the visual high-pressure combustor is provided with the pressure stabilizing cavity which is integrally communicated with the combustion cavity, the volume of the combustion cavity is enlarged in the vertical direction, so that the pressure stabilization in the combustion process can be realized, the smoke can be evacuated, and the smoke influence is reduced. During the experiment, the exhaust valve at the top of the visual high-pressure combustor is manually adjusted, so that the air inlet and the air outlet are balanced, and smoke is timely eliminated. The visual high-pressure combustor has the advantages that the aluminum alloy rotary base is adopted as the base, so that the explosive strips can be quickly replaced, and the experimental efficiency is greatly improved.)

1. The high-pressure combustor experiment system is characterized by comprising a visual high-pressure combustor, a high-speed imaging system, a laser ignition system, a high-pressure gas source supply system and a measurement and control system;

the visual high-pressure combustor comprises a combustion chamber, a pressure stabilizing cavity, an air inlet device, a laser lens, a base and a visual window, wherein a solid propellant strip to be tested is arranged on the base, the base is detachably arranged at the lower end of the combustion chamber, and the solid propellant strip to be tested on the base extends into the combustion chamber; the combustion chamber is communicated with an air inlet device, a pressure stabilizing cavity communicated with the combustion chamber is arranged above the combustion chamber, the top of the pressure stabilizing cavity is connected with a top flange, a laser lens is arranged in the middle of the top flange, the laser lens and the top flange are arranged in a sealing manner, an installation plate is arranged above the top flange, a plurality of installation holes are formed in the installation plate, each installation hole is used for installing external equipment, and the external equipment comprises a pressure gauge, a pressure sensor and an exhaust valve;

the laser ignition system can emit laser to pass through the laser lens and then is incident on the solid propellant strip to be tested in the combustion chamber to ignite the solid propellant strip;

the high-pressure gas source supply system charges high-pressure nitrogen into the visual high-pressure combustor, the high-pressure gas source supply system is connected with the gas inlet device, and the high-pressure nitrogen from the high-pressure gas source supply system enters the combustion chamber through the gas inlet device;

the high-speed imaging system is arranged on one side of the visual window and is used for shooting the combustion process of the solid propellant drug strip to be tested in real time;

the measurement and control system is connected with the laser ignition system, the high-speed imaging system and the pressure sensor, the laser ignition system and the high-speed imaging system are controlled to work in real time, the laser ignition system is controlled to ignite, the high-speed imaging system is synchronously triggered to shoot the combustion process of the solid propellant stick to be tested in real time, meanwhile, picture data shot by the high-speed imaging system are received, the picture data are analyzed and processed, and the combustion speed is measured through an image method.

2. The high-pressure combustor experiment system as claimed in claim 1, wherein the air inlet device comprises an air inlet ring surrounding the outside of the combustion chamber, an air supply interface for connecting the high-pressure air supply system is arranged on the air inlet ring, a plurality of air inlet interfaces communicated with the combustion chamber are uniformly distributed on the air inlet ring, and high-pressure nitrogen from the high-pressure air supply system enters the air inlet ring through the air supply interface and enters the combustion chamber from a plurality of directions of the combustion chamber through the air inlet interfaces on the air inlet ring.

3. The high-pressure combustor experiment system as claimed in claim 1 or 2, wherein visual windows are arranged on the peripheral side walls of the housing of the combustion chamber, the combustion chamber in the combustion chamber is a cylindrical cavity, and a cylindrical pressure stabilizing cavity is communicated with the upper portion of the combustion chamber.

4. The experimental system for the high-pressure combustor of claim 3, wherein the bottom of the outer casing of the combustion chamber is provided with a clamping seat for sealing and connecting the base, a plurality of concave/convex structures are annularly distributed on the inner side of the clamping seat, a plurality of concave/convex structures matched with the concave/convex structures of the clamping seat are arranged on the outer side of the base, more than one layer of sealing rings are arranged between the base and the clamping seat, and the sealing and pressure-bearing of the base are realized through the concave/convex structures and the sealing rings matched with each other between the base and the clamping seat.

5. The high pressure combustor experiment system of claim 1, 2 or 4, wherein a handle is provided outside the base.

6. The high-pressure combustor experiment system of claim 5, wherein the base is provided with an ignition wire column, a fixing plate for fixing the ultrasonic probe is arranged on the base, the ultrasonic probe is mounted on the fixing plate through a nut, a coupling material layer for fixing the solid propellant stick to be tested and realizing sealing and pressure bearing is arranged on the upper end surface of the base extending into the combustion chamber, the coupling material layer is fixed on the upper end surface of the base through a pretightening force component, the visual high-pressure combustor can ignite the solid propellant stick to be tested in the combustion chamber through the ignition wire column on the base, and the combustion speed is measured through an ultrasonic method through the ultrasonic probe.

7. Visual high-pressure combustor, its characterized in that: the device comprises a combustion chamber, a pressure stabilizing cavity, an air inlet device, a laser lens, a base and a visual window, wherein a solid propellant medicine strip to be tested is arranged on the base, the base is detachably arranged at the lower end of the combustion chamber, and the solid propellant medicine strip to be tested on the base extends into the combustion chamber; the combustion chamber is provided with a visual window on the peripheral side wall, the combustion chamber is communicated with an air inlet device, a pressure stabilizing cavity communicated with the combustion chamber is arranged above the combustion chamber, the top of the pressure stabilizing cavity is connected with a top flange, a laser lens is arranged in the middle of the top flange, the laser lens and the top flange are arranged in a sealing manner, an installation plate is arranged above the top flange, a plurality of installation holes are formed in the installation plate, each installation hole is used for installing external equipment, and the external equipment comprises a pressure gauge, a pressure sensor and an exhaust valve; the base is provided with the ignition wire post, is provided with the fixed plate that is used for fixed ultrasonic transducer on the base, and ultrasonic transducer passes through the nut and installs on the fixed plate, and the base stretches into to be provided with on the up end of combustion chamber and is used for fixed solid propellant stick of waiting to test to realize the coupling material layer of sealed pressure-bearing simultaneously, and the coupling material layer passes through the pretightning force part to be fixed at the up end of base, and the ignition wire post on the visual high pressure combustor accessible base ignites the solid propellant stick of waiting to test in the combustion chamber, realizes the supersonic wave method through ultrasonic transducer and surveys the speed of burning.

8. The visual high-pressure combustor according to claim 7, wherein the air inlet device comprises an air inlet ring surrounding the outer side of the combustion chamber, an air supply interface for connecting a high-pressure air source supply system is arranged on the air inlet ring, a plurality of air inlet interfaces communicated into the combustion chamber are uniformly distributed on the air inlet ring, high-pressure nitrogen from the high-pressure air source supply system enters the air inlet ring through the air supply interface, and enters the combustion chamber from multiple directions of the combustion chamber through the air inlet interfaces on the air inlet ring.

9. The visual high-pressure combustor according to claim 7 or 8, characterized in that visual windows are arranged on the peripheral side walls of the housing of the combustion chamber, the combustion chamber in the combustion chamber is a cylindrical cavity, and a cylindrical pressure stabilizing cavity is communicated above the combustion chamber.

10. The visual high-pressure combustor according to claim 9, wherein a base seat for sealing and connecting with a base is disposed at a bottom of the outer shell of the combustion chamber, a plurality of concave/convex structures are annularly distributed inside the base seat, a plurality of concave/convex structures matched with the concave/convex structures of the base seat are disposed outside the base seat, more than one layer of sealing ring is disposed between the base seat and the base seat, and the base seat is sealed and pressure-bearing by the concave/convex structures and the sealing ring matched with each other between the base seat and the base seat.

Technical Field

The invention relates to the technical field of solid propellant combustion diagnosis, in particular to a high-pressure combustor experiment system for researching solid propellant combustion parameters and a visual high-pressure combustor.

Background

The solid rocket engine has the advantages of simple structure, easy storage, convenient use and maintenance, quick response and the like. The addition of a metal combustion agent to the solid propellant can improve the specific impulse of the propellant and inhibit the instability of combustion. The aluminum powder is widely applied to solid propellants due to the advantages of high density, low oxygen consumption, high combustion energy and the like, so that the aluminum-based solid propellant is widely applied to various weapons and equipment such as missiles, rockets and the like. However, the early development of the solid propellant is mainly engineering traction, so that the research on the combustion mechanism of the solid propellant is relatively delayed, and further development of the solid engine is restricted.

At present, the research on the combustion characteristics of solid propellants at home and abroad takes an aluminum-based solid propellant as an example, the method is mainly based on a high-pressure combustor, on one hand, the method is based on a closed high-pressure combustor, a quenching device or a product collecting tank is used for collecting combustion products of the propellant, and condensed phase product analysis is carried out, and on the other hand, the method is mainly used for dynamically researching the combustion process of aluminum particles by using a quartz glass window.

At present, the research methods for the combustion characteristics of the aluminum-based propellant mainly comprise a product analysis method based on a closed high-pressure combustor, a direct-photographing method based on a high-speed camera and a windowing high-pressure combustor, and a holographic method combining digital holography and the windowing high-pressure combustor.

The experimental pressure of a product analysis method can generally reach more than 5MPa, but the combustion process is invisible, the obtained product belongs to a final product of combustion, parameters such as particle size and the like are large, understanding knowledge of the ignition combustion process is lacked, even a condensed phase product obtained by a quenching method is influenced by a quenching distance and quenching liquid, and dynamic processes such as melting, aggregation, agglomeration, micro-explosion and the like of metal particles in a propellant cannot be revealed. The windowing high-pressure combustor basically adopts a flange structure to bear pressure in a sealing mode, the windowing high-pressure combustor is used for repeatedly and uselessly screwing nuts for a large amount of time, and the experimental efficiency is low.

The direct-shooting method realizes the visualization of the combustion process, but the direct-shooting method is basically below 5MPa (lower than the actual engine working pressure) at present, and the pressure needs to be further improved; the influence of smoke under high pressure is large, so that the particle imaging quality is low, and the particle identification error is increased; the windowing high-pressure combustor is sealed and pressure-bearing by adopting a nut flange structure, and the experimental efficiency is low.

The holographic method solves the problem that the depth of field of a high-speed camera is small, but the disadvantage that the high-speed camera is easily affected by smoke is enlarged, so that the existing propellant combustion test can only achieve 1MPa, and the experimental pressure and the actual working pressure of an engine have a certain difference; secondly, the windowing high-pressure combustor is mostly sealed in a pressure bearing mode through a flange structure, and therefore the experiment efficiency is low.

Disclosure of Invention

The invention provides a high-pressure combustor experimental system and a visual high-pressure combustor which can observe the working pressure of an engine under the condition of being close to the working pressure of the engine, based on a solid propellant microscopic combustion experiment and aims to solve the problems of high pressure, smoke and the like. The invention further improves the experimental pressure, effectively solves the problem of high-pressure smoke and greatly improves the experimental efficiency.

In order to achieve the technical purpose, the technical scheme of the invention is as follows:

the high-pressure combustor experiment system comprises a visual high-pressure combustor, a high-speed imaging system, a laser ignition system, a high-pressure air source supply system and a measurement and control system;

the visual high-pressure combustor comprises a combustion chamber, a pressure stabilizing cavity, an air inlet device, a laser lens, a base and a visual window, wherein a solid propellant strip to be tested is arranged on the base, the base is detachably arranged at the lower end of the combustion chamber, and the solid propellant strip to be tested on the base extends into the combustion chamber; the combustion chamber is characterized in that a visual window is arranged on the peripheral side wall of the combustion chamber, the combustion chamber is communicated with an air inlet device, a pressure stabilizing cavity communicated with the combustion chamber is arranged above the combustion chamber, the top of the pressure stabilizing cavity is connected with a top flange, a laser lens is arranged in the middle of the top flange, the laser lens and the top flange are arranged in a sealing mode, a mounting plate is arranged above the top flange, a plurality of mounting holes are formed in the mounting plate, each mounting hole is used for mounting external equipment, and the external equipment comprises a pressure gauge, a pressure sensor and an. The pressure gauge and the pressure sensor detect and know the pressure condition in the combustion chamber in real time, and the exhaust valve can be used for discharging smoke.

The laser ignition system can emit laser to pass through the laser lens and then irradiate the solid propellant powder strip to be tested in the combustion chamber to ignite the solid propellant powder strip.

The high-pressure gas source supply system charges high-pressure nitrogen into the visual high-pressure combustor, the high-pressure gas source supply system is connected with the gas inlet device, and the high-pressure nitrogen from the high-pressure gas source supply system enters the combustion chamber through the gas inlet device.

The high-speed imaging system is arranged on one side of the visual window and is used for shooting the combustion process of the solid propellant drug strip to be tested in real time.

The measurement and control system is connected with the laser ignition system, the high-speed imaging system and the pressure sensor, the laser ignition system and the high-speed imaging system are controlled to work in real time, the laser ignition system is controlled to ignite, the high-speed imaging system is synchronously triggered to shoot the combustion process of the solid propellant stick to be tested in real time, meanwhile, picture data shot by the high-speed imaging system are received, the picture data are analyzed and processed, and the combustion speed is measured through an image method.

The base is an aluminum alloy rotary base. During the experiment, firstly, the aluminum alloy rotary base is adopted to fix the solid propellant strip to be tested to the center of the visible window, secondly, the high-speed imaging system is adjusted until the focal plane of the high-speed imaging system is in the center of the solid propellant strip to be tested, the high-pressure nitrogen is filled into the combustion chamber of the visual high-pressure combustor by the high-pressure air source supply system, the laser ignition system, the pressure sensor and the high-speed camera of the high-speed imaging system are synchronously triggered by the measurement and control system, the experiment is started, and finally, after the experiment is completed, the high-pressure air and combustion products are discharged by manually adjusting the exhaust valve, the aluminum alloy rotary base is taken. Parameters such as agglomerate grain size distribution, movement speed and the like can be obtained by combining an image processing technology.

As a preferred scheme, the air inlet device includes the ring of admitting air that encircles outside the combustion chamber, be provided with the air feed interface that is used for connecting high-pressure air supply system on the ring of admitting air, evenly distributed is a plurality of air feed interfaces that communicate in the combustion chamber that communicate on the ring of admitting air, and the high-pressure nitrogen gas that comes from high-pressure air supply system enters into the ring of admitting air through the air feed interface, enters into the combustion chamber from a plurality of directions of combustion chamber through the interface of admitting air on the ring of admitting air.

As the preferred scheme, all be provided with the visual window on the lateral wall all around of the shell of combustion chamber, the combustion chamber in the combustion chamber is cylindrical cavity, and cylindrical pressure stabilizing cavity is communicate to the combustion chamber top.

As the preferred scheme, the bottom of the shell of the combustion chamber is provided with a clamping seat used for being hermetically connected with a base, a plurality of concave/convex structures are annularly distributed on the inner side of the clamping seat, the outer side of the base is provided with a plurality of concave/convex structures matched with the concave/convex structures of the clamping seat, more than one layer of sealing ring is arranged between the base and the clamping seat, and the sealing bearing of the base is realized through the concave/convex structures and the sealing ring which are mutually matched between the base and the clamping seat.

Preferably, a handle is arranged on the outer side of the base.

As the preferred scheme, the base is provided with the ignition wire column, is provided with the fixed plate that is used for fixed ultrasonic probe on the base, and ultrasonic probe passes through the nut and installs on the fixed plate, is provided with on the up end that the base stretches into the combustion chamber to be used for fixed solid propellant stick to be tested and realizes the coupling material layer of sealed pressure-bearing simultaneously, and the coupling material layer passes through the pretightning force part to be fixed at the up end of base, and the ignition wire column on visual high pressure combustor accessible base ignites the solid propellant stick to be tested in the combustion chamber, realizes the ultrasonic method through ultrasonic probe and surveys the burning rate.

The invention provides a visual high-pressure combustor which comprises a combustion chamber, a pressure stabilizing cavity, an air inlet device, a laser lens, a base and a visual window, wherein a solid propellant strip to be tested is arranged on the base, the base is detachably arranged at the lower end of the combustion chamber, and the solid propellant strip to be tested on the base extends into the combustion chamber; the combustion chamber is provided with a visual window on the peripheral side wall, the combustion chamber is communicated with an air inlet device, a pressure stabilizing cavity communicated with the combustion chamber is arranged above the combustion chamber, the top of the pressure stabilizing cavity is connected with a top flange, a laser lens is arranged in the middle of the top flange, the laser lens and the top flange are arranged in a sealing manner, an installation plate is arranged above the top flange, a plurality of installation holes are formed in the installation plate, each installation hole is used for installing external equipment, and the external equipment comprises a pressure gauge, a pressure sensor and an exhaust valve; the base is provided with the ignition wire post, is provided with the fixed plate that is used for fixed ultrasonic transducer on the base, and ultrasonic transducer passes through the nut and installs on the fixed plate, and the base stretches into to be provided with on the up end of combustion chamber and is used for fixed solid propellant stick of waiting to test to realize the coupling material layer of sealed pressure-bearing simultaneously, and the coupling material layer passes through the pretightning force part to be fixed at the up end of base, and the ignition wire post on the visual high pressure combustor accessible base ignites the solid propellant stick of waiting to test in the combustion chamber, realizes the supersonic wave method through ultrasonic transducer and surveys the speed of burning.

To visual high-pressure combustor, as its preferred scheme, air inlet unit is including encircleing the ring that admits air in the combustion chamber outside, it is provided with the air feed interface that is used for connecting high-pressure air supply feed system to admit air on the ring, admit air a plurality of air feed interfaces that communicate in the combustion chamber of evenly distributed on the ring, the high-pressure nitrogen gas that comes from high-pressure air supply feed system enters into the ring of admitting air through the air feed interface, enters into in the combustion chamber from a plurality of directions of combustion chamber through the interface of admitting air on the ring of admitting air.

As the optimal scheme of the visual high-pressure combustor, visual windows are arranged on the peripheral side walls of the shell of the combustion chamber, the combustion chamber in the combustion chamber is a cylindrical cavity, and a cylindrical pressure stabilizing cavity is communicated with the upper portion of the combustion chamber.

For the visual high-pressure combustor, as the preferred scheme, the shell bottom of combustion chamber is provided with the cassette that is used for sealing connection base, and the inboard annular distribution of cassette has a plurality of concave/boss structures, the base outside is provided with a plurality of concave/boss structures with cassette indent/boss structure matched with, is provided with the sealing washer more than the one deck between base and the cassette, realizes the sealed pressure-bearing of base through the concave/boss structure and the sealing washer of mutually supporting between base and cassette.

Compared with the prior art, the invention has the beneficial effects that at least:

the method is used for the microscopic combustion mechanism research of the aluminum-based solid propellant under the working pressure close to the actual solid engine, and is mainly used for researching the microscopic combustion behaviors of melting, aggregation, agglomeration and the like of aluminum particles in the solid propellant. The propellant combustion process was visualized using a high speed camera imaging system and four quartz glass windows. The air inlet, the air exhaust and the blowing-off of the visual high-pressure combustor can be remotely controlled by utilizing the electromagnetic valve and the pneumatic valve, so that the safety of the experiment is improved. Further, the synchronization of the ignition, the pressure acquisition and the high-speed camera can be realized based on an NI (National Instruments, hereinafter referred to as NI) acquisition card and Labview software.

The invention can realize the visual microscopic combustion test of the propellant under 10 MPa. The visual high-pressure combustor adopts a bottom-up annular air inlet mode, can blow away smoke in a visual field, and effectively reduces the influence of propellant on smoke combustion. Meanwhile, the upper part of the visual high-pressure combustor is provided with the pressure stabilizing cavity which is integrally communicated with the combustion cavity, the volume of the combustion cavity is enlarged in the vertical direction, so that the pressure stabilization in the combustion process can be realized, the smoke can be evacuated, and the smoke influence is reduced. During the experiment, the exhaust valve at the top is manually adjusted, so that the air inlet and the air outlet are balanced, and the smoke is timely discharged. The visual high-pressure combustor has the advantages that the aluminum alloy rotary base is adopted as the base, so that the explosive strips can be quickly replaced, and the experimental efficiency is greatly improved.

The invention can be used for the microscopic combustion experimental study of the aluminum-based solid propellant, and can also be used for similar study of other boron, magnesium or alloy-containing solid propellants. The invention can be provided with a collecting tank at the base position, and can be used for analyzing the combustion products of the solid propellant, and further can be used for performing a combustion product analysis experiment of more than 10MPa when the glass sheet of the visual window is replaced by an aluminum block. The wheel type movable support can be designed on the visual high-pressure combustor, and can be matched with a holographic light path system to perform holographic experiments.

The invention can realize dynamic burning rate test: on one hand, an image method can be adopted, based on pictures shot by a high-speed camera and an image processing program, the camera is calibrated to measure the combustion surface retreating distance, and then the propellant combustion speed parameter can be obtained according to the frame frequency; on the other hand, the combustion speed parameter of the propellant can be obtained by adopting an ultrasonic method and utilizing the time difference of ultrasonic echo reflection.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic diagram of the structure of an embodiment;

FIG. 2 is a schematic structural diagram of a high-pressure visual combustor provided by an embodiment;

FIG. 3 is a front view of a visual high pressure combustor provided by an embodiment;

FIG. 4 is a cross-sectional view A-A of FIG. 3;

FIG. 5 is a schematic diagram of a base according to an embodiment;

FIG. 6 is a cross-sectional view of FIG. 5;

FIG. 7 is a schematic view of the sealing and pressure-bearing of the base;

FIG. 8 is a schematic intake view of the intake ring;

FIG. 9 is a schematic view of the direction of flow of the high pressure air supply in the high pressure combustor.

Reference numbers in the figures:

1. a visual high pressure combustor; 2. a high-speed imaging system; 3. a laser ignition system; 4. a high pressure gas supply system; 5. a measurement and control system; 5001. a computer; 5002. an NI acquisition control card; 101. a combustion chamber; 102. a voltage stabilizing cavity; 103. a laser lens; 104. a visual window; 105. an air inlet ring; 106. an air supply interface; 107. an air inlet interface; 108. a combustion chamber housing; 109. a combustion chamber; 110. a side flange; 111. side glass; 112. a top flange; 113. mounting a plate; 114. mounting holes; 115. a base; 116. a voltage stabilization cavity housing; 117. a card holder; 118. a concave/convex structure; 119. a seal ring; 120 of a solvent; an ignition wire column; 121. a fixing plate; 122. an ultrasonic probe; 123. a layer of coupling material; 124. a pre-tightening force component; 125. a base handle.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; the connection can be mechanical connection, electrical connection, physical connection or wireless communication connection; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, the technical solutions in the embodiments of the present invention may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

The invention is based on a visual high-pressure combustor experiment system, is mainly used for solving the observation problem of the mesoscopic combustion process of the aluminum-based solid propellant under high pressure, further has deep knowledge on the combustion mechanism of the propellant and the agglomeration rule of aluminum particles, and provides a certain experimental data support for the establishment and the perfection of a mesoscopic combustion model of the propellant.

Referring to fig. 1, the present embodiment provides a high-pressure combustor experiment system, which includes a visual high-pressure combustor 1, a high-speed imaging system 2, a laser ignition system 3, a high-pressure gas source supply system 4, and a measurement and control system 5.

Referring to fig. 2, 3 and 4, the visual high-pressure combustor in one embodiment comprises a combustion chamber 101, a pressure stabilizing cavity 102, an air inlet device, a laser lens 103, a visual window 104 and a solid propellant stick, wherein the solid propellant stick is arranged on a base 115, the base 115 is detachably mounted at the lower end of the combustion chamber 101, and the solid propellant stick to be tested on the base 115 extends into the combustion chamber 101; the combustion chamber 101 is provided with a visual window 104 on the peripheral side wall, the combustion chamber 101 is communicated with an air inlet device, a pressure stabilizing cavity 102 communicated with the combustion chamber is arranged above the combustion chamber 101, the top of the pressure stabilizing cavity 102 is connected with a top flange 112, a laser lens 103 is arranged in the middle of the top flange 112, the laser lens 103 and the top flange 112 are arranged in a sealing mode, an installation plate 113 is arranged above the top flange 112, a plurality of installation holes 114 are formed in the installation plate 113, each installation hole 114 is used for installing external equipment, the installation holes 114 are used for installing a pressure gauge and a precise pressure sensor for detecting the pressure condition in the combustion chamber in real time, and the installation holes 114 are also used for installing an exhaust. The external device that can be mounted in the mounting hole 114 is not limited thereto, and other external devices may be selectively mounted as needed.

The laser ignition system can emit laser to pass through the laser lens and then irradiate the solid propellant powder strip to be tested in the combustion chamber to ignite the solid propellant powder strip. The laser ignition system mainly comprises a solid laser generator, a laser output optical cable with a laser output collimation head and a laser controller. The solid laser generator is used for generating laser with continuously adjustable power (0-100W) and 1080nm wavelength, and can generate red tracing laser and prevent laser accidental injury. The laser output optical cable (3 m) with the laser output collimation head can flexibly adjust the laser direction. The laser controller is used for switching on and off the laser and adjusting the laser power. The laser lens in the visual high-pressure combustor is made of quartz glass, and the attenuation coefficient of the laser lens to the wavelength is small (10% -20%). Experiments prove that the laser can ignite the solid propellant powder strips to be tested in the combustion chamber through the laser lens, the laser ignition system is connected to the NI acquisition control card, and the measurement and control system can realize synchronous triggering of the laser ignition system.

The high-pressure gas source supply system charges high-pressure nitrogen into the visual high-pressure combustor, the high-pressure gas source supply system is connected with the gas inlet device, and the high-pressure nitrogen from the high-pressure gas source supply system enters the combustion chamber through the gas inlet device. The total pressure of the air source of the high-pressure air source supply system is 16MPa, and the requirement of the experiment on the pressure can be met. The air inlet and exhaust control of the high-pressure air source supply system are controlled by the electromagnetic valve, the experimental air source is divided into two paths, one path of control air (larger than 4 MPa) is introduced into the electromagnetic valve, the on-off of the control air is controlled by the circuit, the other path of control air is introduced into the pneumatic valve, and the on-off of the pneumatic valve is controlled by the electromagnetic valve. Based on the method, the visual high-pressure combustor can be remotely controlled, and the experimental safety is improved; be provided with manual relief valve in the experiment pipeline, but emergency pressure release avoids the risk.

The high-speed imaging system is arranged on one side of the visual window and is used for shooting the combustion process of the solid propellant drug strip to be tested in real time. The high-speed imaging system comprises a high-speed camera, a lens, a data line, a signal trigger line and the like, the frame frequency of the high-speed camera can reach 20000 frames per second, the minimum exposure time can reach one million seconds, the experimental requirement can be met, and the signal trigger line is connected into the measurement and control system, so that the synchronous triggering of the high-speed camera can be realized.

The measurement and control system 5 is connected with the laser ignition system, the high-speed imaging system and the pressure sensor, controls the laser ignition system and the high-speed imaging system to work in real time, controls the laser ignition system to ignite, synchronously triggers the high-speed imaging system to shoot the combustion process of the solid propellant stick to be tested in real time, receives picture data shot by the high-speed imaging system, analyzes and processes the picture data, and measures the combustion speed through an image method. The measurement and control system 5 is composed of a computer 5001, an NI acquisition control card 5002, a pressure sensor data line and a signal line, wherein the pressure sensor is connected to the top of the visual high-pressure combustor and can measure the pressure change inside a combustion chamber of the visual high-pressure combustor in real time. And the ignition, the synchronous triggering of the camera and the pressure sensor and the data transmission and storage are realized through a measurement and control system.

The base is an aluminum alloy rotary base. The solid propellant strips to be tested are cut into specified specifications (5 x 10 mm) by utilizing a cut-off knife, fixed on an aluminum alloy rotary base, the aluminum alloy rotary base is screwed into the visual high-pressure combustor, and the direction of the strips is adjusted to ensure that the side faces are opposite to the visual window. The parameters (frame frequency, exposure time, magnification and the like) of the camera are adjusted to enable the focal plane of the high-speed camera to be located at the central plane of the solid propellant drug strip to be tested. Opening a high-pressure gas source supply system, filling high-pressure nitrogen into the visual high-pressure combustor to a specified pressure (more than 5 MPa) and stabilizing, roughly judging the size and stability of the pressure value through a pressure gauge, and based on an NI acquisition control card, synchronously controlling the ignition of the solid laser, the triggering of the high-speed camera and the acquisition of a pressure signal by using a computer; after the experiment is finished, the lower pressure and the image data are firstly stored, then the combustion products are blown out by blowing off transiently, then the high-pressure gas is discharged by manually adjusting the exhaust valve, and the aluminum alloy rotary base is taken down to replace the explosive strip for repeated experiments. Parameters such as agglomerate grain size distribution, movement speed and the like can be obtained by combining an image processing technology.

Referring to fig. 2, 3 and 4, the present example provides a visual high-pressure burner that can perform combustion tests of aluminum-based solid propellants at 10 MPa.

Visual high-pressure combustor, including combustion chamber 101, pressure stabilizing cavity 102, air inlet unit, laser lens 103, base 115, visual window 104, treat that the test solid propellant medicine strip is arranged in on base 115, and base 115 is the aluminium alloy and revolves formula base, demountable installation at the lower extreme of combustion chamber 101, treat on the base 115 that the test solid propellant medicine strip stretches into the combustion chamber of combustion chamber 101. The base 115 of the visual high-pressure combustor is made of aluminum alloy materials, and the combustion chamber shell 108, the pressure stabilizing cavity shell 116 and the like can be made of stainless steel materials. The combustion chamber housing 108 and the plenum housing 116 are integrally formed, and the combustion chamber 109 and the plenum 102 are through.

The combustion chamber housing is cuboid, and the combustion chamber housing 108 has a cylindrical combustion chamber 109 inside. The upper part of the combustion chamber 109 is communicated with a cylindrical pressure stabilizing chamber 102. In one embodiment the length, width and height dimensions of the combustion chamber housing are 126 x 115mm, and the height of the combustion chamber within it is 115mm and the diameter is 80 mm. The inner diameter of the pressure stabilizing cavity 102 is 80mm, the height of the pressure stabilizing cavity is 102mm, the shell of the pressure stabilizing cavity is cylindrical, and the wall thickness of the pressure stabilizing cavity is 8 mm.

The viewing windows 104 are arranged on the peripheral side walls of the cuboid combustion chamber shell 108, each viewing window 104 is composed of a side flange 110 and side glass 114, the outer diameter of each side flange 110 is 99mm, the side flanges are fixed by 10M 8 stainless steel nuts, and each side glass 114 is cylindrical, 40mm in thickness and 70mm in diameter.

The combustion chamber 101 is communicated with an intake device. The air inlet device comprises an air inlet ring 105 surrounding the outer side of the combustion chamber 101, an air supply interface 106 used for being connected with a high-pressure air source supply system is arranged on the air inlet ring 105, a plurality of air inlet interfaces 107 communicated into the combustion chamber are uniformly distributed on the air inlet ring 105, high-pressure nitrogen from the high-pressure air source supply system enters the air inlet ring 105 through the air supply interface 106, and enters the combustion chamber 101 from a plurality of directions of the periphery of the combustion chamber through the air inlet interfaces 107 on the air inlet ring 105. In one embodiment, the air inlet ring is an air inlet ring 105 with a central diameter of 268mm, and the air inlet ring 105 is provided with an air supply interface 106 with an inner diameter of 10 mm. Four air inlet ports 107 with the inner diameter of 4mm are orthogonally distributed on the air inlet ring 105, and high-pressure nitrogen gas is charged into the combustion chamber from four directions of the combustion chamber. FIG. 8 is a schematic intake view of the intake ring; FIG. 9 is a schematic view of the direction of flow of the high pressure air supply in the high pressure combustor. The air inlet ring 105 is connected with a high-pressure air source supply system through an air supply interface 106, four air inlet interfaces 107 are introduced into the combustion chamber from four directions, the purpose of annular air inlet is achieved, and airflow in the combustion chamber is discharged from bottom to top.

The top of the pressure stabilizing cavity 102 is connected with a top flange 112, a laser lens 103 is arranged in the middle of the top flange 112, the laser lens 103 and the top flange 112 are arranged in a sealing mode, a mounting plate 113 is arranged above the top flange 112, a plurality of mounting holes 114 used for mounting external equipment are formed in the mounting plate 113, and each mounting hole 114 is respectively used for mounting a pressure gauge for detecting the pressure condition in a combustion chamber in real time and a precise pressure sensor and an exhaust valve for exhausting. The external device that can be mounted in the mounting hole 114 is not limited thereto, and other external devices may be selectively mounted as needed.

As shown in fig. 5, 6 and 7, the present embodiment provides an aluminum alloy spin base. The problem that nut flange structure wastes time and energy is solved on the one hand, and on the other hand aluminum alloy base has reduced the quality, makes the experiment light easily operation relatively, has improved experimental efficiency. An ignition wire column 120 and an ultrasonic combustion rate measuring module are arranged in the base.

The base 115 is provided with an ignition wire column 120, the base 115 is provided with a fixing plate 121 for fixing an ultrasonic probe 122, the ultrasonic probe 122 is installed on the fixing plate 121 through a nut, the base 115 extends into the combustion chamber 109, the upper end face of the base 115 is provided with a coupling material layer 123 for fixing a solid propellant strip to be tested and realizing sealing and pressure bearing, and the coupling material layer 123 is fixed on the upper end face of the base 115 through a pre-tightening force component 124. The visual high-pressure combustor can ignite the solid propellant powder strips to be tested in the combustion chamber through the ignition wire columns on the base, and the combustion speed is measured by an ultrasonic method through the ultrasonic probe. The coupling material layer is made of a coupling material and is a material with less ultrasonic attenuation. A base handle 125 is also provided on the outside of the base 115 to facilitate removal and installation of the base. Thus, the visual high-pressure combustor has two ignition modes, one is laser ignition, namely, laser emitted by a laser ignition system passes through a laser lens and is incident on a solid propellant stick to be tested in a combustion chamber to ignite the solid propellant stick, and the other is that a metal wire ignition wire column is arranged on a base, so that the solid propellant stick to be tested in the combustion chamber can be ignited.

The invention can realize dynamic burning rate test: on one hand, an image method is adopted, based on pictures shot by a high-speed camera and an image processing program, the camera is calibrated to measure the combustion surface retreating distance, and then the propellant combustion speed parameter can be obtained according to the frame frequency; and on the other hand, the combustion speed parameter of the propellant can be obtained by adopting an ultrasonic method and utilizing the time difference of ultrasonic echo reflection detected by an ultrasonic probe on the base.

The bottom of the combustion chamber shell 108 is provided with a clamping seat 117 for sealing connection with a base 115, a plurality of concave/convex structures 118 are annularly distributed on the inner side of the clamping seat 117, the outer side of the base 115 is provided with a plurality of concave/convex structures 118 matched with the concave/convex structures of the clamping seat 117, more than one layer of sealing ring 119 is arranged between the base 115 and the clamping seat 117, and the sealing pressure bearing of the base 117 is realized through the concave/convex structures 118 and the sealing ring which are matched with each other between the base 115 and the clamping seat 117. FIG. 7 is a schematic view of the sealing and pressure-bearing of an aluminum alloy rotary base; the aluminum alloy revolves formula base and pushes up according to the arrow direction and is higher than cassette concave/boss structure upper surface a little to the lower surface of base concave/boss structure, then revolves formula base according to the rotatory aluminum alloy of arrow direction shown in the figure, because concave/boss structure both sides height on the base is highly inconsistent (one side 19.33mm, opposite side 20.14 mm), can lead to sealed face to compress tightly the rubber circle in the seal groove gradually, thereby reach sealed effect, when revolving to the deepest, concave/boss structure on the cassette and the concave/boss structure coincidence part on the base have constituted the pressure-bearing structure of visual high pressure combustor base.

The invention provides a novel air inlet mode, which adopts a bottom-up annular air inlet mode to effectively reduce the influence of smoke on experimental observation, and adopts a mode of advancing and discharging simultaneously to further reduce the influence of smoke. The pressure stabilizing cavity is arranged, so that pressure fluctuation can be reduced for pressure requirement experiments, volume is increased, and smoke influence can be reduced.

The invention can adopt laser ignition and image method to measure burning speed, and adopt metal wire ignition and ultrasonic method to measure burning speed. The visual window is arranged on the side surface of the combustion chamber, and the visualization of the combustion field can be realized by combining the visual window with the high-speed camera. The pressure stabilizing cavity integrated with the combustion cavity enlarges the volume of the combustion chamber and reduces the influence of smoke on imaging. The top flange is matched with the rubber ring and the nut to realize top sealing and bearing.

Compared with a product analysis method, the method can realize visualization of the combustion process, and can observe the microscopic combustion process of micron-sized aluminum particles based on a high-speed camera.

Compared with the traditional windowing high-pressure combustor, the invention has higher pressure and can realize a propellant microscopic combustion experiment under 10 MPa.

The aluminum alloy rotary base designed by the invention gets rid of the constraint of a nut flange structure on the experimental process, and on the other hand, compared with a stainless steel base, the aluminum alloy rotary base has the advantages of reduced quality, easiness in experimental operation and capability of greatly improving the experimental efficiency.

The design of the pressure stabilizing cavity can stabilize the experimental pressure and increase the volume of the combustion chamber to relieve the influence of smoke.

The design of the air intake and exhaust mode adopts a mode of annular air intake from bottom to top, can effectively inhibit the influence of smoke on the imaging of a high-speed camera, and simultaneously adopts the mode of coexistence of air intake and exhaust in the experimental process to further reduce the influence of smoke.

The experimental system is built, pressure test is successfully passed, and capture of aluminum particle microscopic combustion process in the combustion process of aluminum-based NEPE (high-energy composite solid propellant) under 7MPa can be realized according to the experimental steps in the technical scheme.

In summary, although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention.