CN217004537U - Disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation - Google Patents
Disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation Download PDFInfo
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- CN217004537U CN217004537U CN202220152362.2U CN202220152362U CN217004537U CN 217004537 U CN217004537 U CN 217004537U CN 202220152362 U CN202220152362 U CN 202220152362U CN 217004537 U CN217004537 U CN 217004537U
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- 238000002485 combustion reaction Methods 0.000 title claims abstract description 71
- 238000005474 detonation Methods 0.000 title claims abstract description 51
- 239000000446 fuel Substances 0.000 claims abstract description 26
- 230000003287 optical effect Effects 0.000 claims abstract description 22
- 239000007921 spray Substances 0.000 claims abstract description 12
- 238000002347 injection Methods 0.000 claims abstract description 5
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- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
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- 239000003380 propellant Substances 0.000 description 1
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- 238000012360 testing method Methods 0.000 description 1
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Abstract
The utility model discloses a disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation, and particularly relates to the technical field of ramjet engines. The fuel injection device comprises two cover plates, wherein a disc-shaped cavity is formed between the two cover plates, an air collecting cavity, a supersonic speed accelerating section, an expanding section and a combustion chamber are sequentially arranged in the cavity from the center to the edge, the thickness of the air collecting cavity is greater than that of the supersonic speed accelerating section, the expanding section is in a horn shape, one side with a small opening is connected with the supersonic speed accelerating section, a plurality of fuel spray holes are distributed in the supersonic speed expanding section in the circumferential direction, and optical observation windows are arranged on the supersonic speed accelerating section and the combustion chamber; an air inlet communicated with the air collection cavity is formed in the center of any cover plate, a plurality of lifting lugs are arranged on each cover plate, and the two lifting lugs corresponding to each other are connected through bolts. The technical scheme of the utility model solves the problem that the conventional rotary detonation combustor is not beneficial to the formation and observation of the supersonic flow field, and can be used for observing a specific wave system structure under the rotary detonation back pressure.
Description
Technical Field
The utility model relates to the technical field of ramjet engines, in particular to a disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation.
Background
In the rotary knocking ramjet engine, the knocking wave is rotationally propagated in the combustion chamber at high speed, the frequency reaches thousands of hertz, the peak pressure can reach several megapascals, and the pressure in the combustion chamber has obvious difference along the circumferential direction, so that high-frequency periodic pulsating pressure is formed. The complicated and severe combustion back pressure environment can influence the flow process in the supersonic speed acceleration section, and can cause the blockage of an air inlet channel and the non-starting in severe cases; meanwhile, the combustion back pressure is coupled with the flowing and mixing process of the propellant, and the stable propagation of the rotary detonation wave is greatly influenced. Therefore, the research on interaction between the rotary detonation back pressure and the supersonic velocity incoming flow is carried out, the fuel injection mixing process under the action of the rotary detonation back pressure is clarified, the evolution characteristic of the wave system structure in the supersonic velocity acceleration section along with propagation of the detonation wave is obtained, and the method has important significance for efficient and stable work of the rotary detonation ramjet.
In the experiment, the fuel injection mixing process and the motion evolution law of a shock wave system need to be measured by means of optical equipment such as a high-speed camera and schlieren, and the optical path arrangement of the optical equipment generally requires that the optical path is perpendicular to an observed object, so that the influence of light refraction is reduced. Since the combustion chamber of the conventional rotary detonation ramjet is of a circular ring structure, optical observation of the interaction of the detonation wave and the supersonic incoming flow is difficult to develop. In the prior art, a disc-shaped rotary detonation combustor (as shown in fig. 1) convenient for optical observation exists, fuel and oxidant in the combustor directly participate in rotary detonation combustion reaction after being injected at the head of the combustor, and due to the fact that a supersonic speed acceleration section does not exist, supersonic speed airflow cannot be formed at the upstream of detonation waves, and observation and research of interaction of the detonation waves and supersonic speed inflow cannot be achieved. In addition, most of the fuel and oxidant in the conventional disc-shaped rotary detonation combustion chamber are injected from the outer edge of the combustion chamber, combustion products are sprayed out from the central outlet of the combustion chamber, and the flow channel is in a convergent shape, so that the formation of a supersonic flow field is not facilitated.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide the disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation, and solves the problem that the conventional rotary detonation combustion chamber is not beneficial to formation and observation of a supersonic flow field.
In order to achieve the purpose, the technical scheme of the utility model is as follows: a disc-shaped rotary detonation combustion chamber capable of achieving supersonic flow field observation comprises two cover plates arranged at intervals, wherein a disc-shaped cavity is formed between the two cover plates, an air collecting cavity, a supersonic acceleration section, an expansion section and a combustion chamber are sequentially arranged from the center to the edge of the cavity, the thickness of the air collecting cavity is larger than that of the supersonic acceleration section, the expansion section is horn-shaped, one side with a small opening is connected with the supersonic acceleration section, a plurality of fuel spray holes are circumferentially distributed in the supersonic expansion section, optical observation windows are arranged on the supersonic acceleration section and the combustion chamber, and the optical observation windows are used for schlieren or high-speed camera shooting light path arrangement; an air inlet communicated with the air collection cavity is formed in the center of any cover plate, a plurality of lifting lugs are arranged on each cover plate, and the two lifting lugs which correspond to each other are connected through bolts.
Furthermore, the cross sections of the supersonic speed accelerating section and the combustion chamber are equal straight sections.
Through the arrangement, the optical observation windows are conveniently arranged on the supersonic speed acceleration section and the combustion chamber, and meanwhile, the air flow direction flows from the center of the disc-shaped combustion chamber to the outer diameter direction, so that the flow channel of the disc-shaped combustion chamber is integrally represented as an expansion flow channel, the flow area is continuously increased along the flow direction, the acceleration of the air flow in the supersonic speed acceleration section is conveniently realized, and the heat release addition of fuel in the combustion chamber and the timely discharge of combustion products are facilitated.
Furthermore, a plurality of fuel spray holes are uniformly distributed in the circumferential direction of the expansion section of each cover plate.
Through the arrangement, the problem that the detonation wave is reversely transmitted to the supersonic velocity acceleration section at the upstream of the fuel spray hole is avoided, so that the normal observation of a wave system structure formed by the interaction of the detonation back pressure and the supersonic velocity incoming flow in the supersonic velocity acceleration section is ensured. Meanwhile, the fuel spray holes are uniformly distributed along the circumferential direction, so that the fuel mixing effect is enhanced, and the stable propagation of the rotary detonation wave is ensured.
Furthermore, two first threaded positioning holes distributed at intervals are formed in each lifting lug of the cover plate, and a second threaded positioning hole coaxial with any one first threaded positioning hole is formed in the other lifting lug of the cover plate.
Through the arrangement, the relative angle of the two cover plates can be adjusted, and different arrangement modes (namely, the fuel spray holes on two sides are arranged at intervals or aligned) of the fuel spray holes on the two cover plates are ensured, so that the combustion chamber has the capability of researching the influence effect of the arrangement modes of the different fuel spray holes.
Further, a detonation tube is arranged tangentially at the 1/4 flow direction position of the combustion chamber.
Through the arrangement, the fuel and the oxidant have a certain mixing distance, so that the mixing effect of the fuel and the oxidant is ensured, meanwhile, the arrangement of the detonating tube along the tangential direction can ensure that the hot jet flow generated by the detonating tube enters the combustion chamber in the tangential direction, and the quick establishment of a rotary detonation flow field structure is facilitated.
Compared with the prior art, the beneficial effect of this scheme:
this scheme is compared in the rotatory detonation combustion chamber of conventional annular, and the combustion chamber of disc is favorable to carrying out the light path and arranges, has very big convenience to developing optical observation. Meanwhile, the supersonic speed acceleration section is arranged in the disc-shaped flow channel, so that the air flow can be accelerated to a supersonic speed state, and then the rotary detonation combustion is organized at the downstream of the supersonic speed acceleration section, so that the disc-shaped combustion chamber has the capability of observing the interaction flow field of detonation waves and supersonic speed incoming flows.
Drawings
FIG. 1 is a cross-sectional view of a disk-shaped rotating detonation combustor of the prior art that is readily optically observable;
FIG. 2 is an axial side view of a disk-shaped rotary detonation combustor capable of realizing supersonic flow field observation in embodiment 1;
FIG. 3 is a sectional view of a disc-shaped rotary detonation combustor capable of realizing supersonic flow field observation in embodiment 1;
FIG. 4 is a detailed structural view of a rotary knocking combustion chamber in embodiment 1;
FIG. 5 is a high-frequency pressure map of a rotary knocking combustion chamber in embodiment 1;
FIG. 6 is a pressure cloud of the flow field structure in the rotary detonation combustor in example 1;
FIG. 7 is a density gradient cloud plot of the flow field structure in the rotary detonation combustor in example 1;
fig. 8 is a schematic view of the ultrasonic flow field observation optical path arrangement in example 1.
Detailed Description
The present invention will be described in further detail below by way of specific embodiments:
reference numerals in the drawings of the specification include: the device comprises a cover plate 1, an air gas collecting cavity 2, a supersonic speed accelerating section 3, an expanding section 4, a combustion chamber 5, a fuel spray hole 6, an air inlet 7, a lifting lug 8, a detonating tube 9, an optical observation window 10, a light source 11, a lens 12, a first concave reflector 13, a first plane reflector 14, a second plane reflector 15, a second concave reflector 16, a knife edge 17 and a high-speed camera 18.
Example 1
As shown in figures 2 and 3: a disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation comprises two cover plates 1 which are arranged at intervals and have coincident axes. A disc-shaped cavity is formed between the two cover plates 1, and an air collecting cavity 2, a supersonic speed accelerating section 3, an expanding section 4 and a combustion chamber 5 are sequentially arranged in the cavity from the center to the edge. The thickness of the air collecting cavity 2 is larger than that of the supersonic speed accelerating section 3, the flared section 4 is horn-shaped, one side with a small opening is connected with the supersonic speed accelerating section 3, the cross sections of the supersonic speed accelerating section 3 and the combustion chamber 5 are equal straight sections, the supersonic speed accelerating section 3 and the combustion chamber 5 are both provided with optical observation windows 10, and the optical observation windows 10 are used for schlieren or high-speed camera light path arrangement. A plurality of fuel spray holes 6 are uniformly distributed on the expanding section 4 in the circumferential direction. The center of the cover plate 1 positioned on the left side is provided with an air inlet 7 communicated with the air collecting cavity 2, each cover plate 1 is provided with three lifting lugs 8 which are equidistantly distributed along the circumferential direction, and the two lifting lugs 8 which correspond to each other are connected through bolts. The lifting lug 8 of the left side cover plate 1 is provided with two first threaded positioning holes which are distributed at intervals, and the lifting lug 8 of the right side cover plate 1 is provided with a second threaded positioning hole which is coaxially arranged with any first threaded positioning hole. A squib 9 is arranged tangentially at the 1/4 flow-direction position of the combustion chamber 5.
During operation, high-pressure air flows around after entering into air gas collecting cavity 2 at the center of disc-shaped combustion chamber 5, and gets into expansion section 4 after accomplishing accelerating in supersonic speed acceleration section 3, and the round fuel orifice that distributes in expansion section 4 can make the fuel get into expansion section 4 after and mix with the air incoming flow and form combustible gas mixture, and combustible gas mixture is detonating after getting into combustion chamber 5, can form stable detonation wave in combustion chamber 5, and the high temperature gas that the detonation combustion produced then is discharged around combustion chamber 5.
In order to verify the feasibility of the rotary detonation of the disc-shaped combustion chamber structure proposed in the scheme, the combustion chamber with the structure is subjected to numerical simulation, and the structure and the size of the combustion chamber adopted in the numerical simulation are shown in fig. 4. The fuel and oxidant used were hydrogen and air, respectively. Air entering the air collecting cavity 2 is accelerated in the supersonic acceleration section 3 and then mixed with hydrogen injected in the expansion section 4, then enters the combustion chamber 5 to jointly form rotary detonation combustion, and high-temperature gas generated by combustion is discharged out of the combustion chamber 5 along the periphery. The boundary conditions at the inlet of the air plenum 2 and the injection of hydrogen fuel are shown in table 1 below, with a 100kPa outlet back pressure of the combustion chamber 5.
Table 1:
according to the scheme, the disc-shaped combustion chamber 5 is detonated by adopting a tangential detonation mode, and the pressure curve of the combustion chamber 5 with uniform oscillation as shown in fig. 5 is finally obtained after a certain period of time of adjustment, so that the stably propagated detonation wave is formed in the disc-shaped combustion chamber 5. The combustion chamber 5 pressure monitoring data shows that the propagation frequency of the knock wave is 1562.5Hz, and the propagation velocity of the knock wave can be calculated to be about 2258m/s in combination with the inner diameter of the disc combustion chamber 5. From the flow field structures of the disk combustion chamber 5 shown in fig. 6 and 7, it can be seen that the air is accelerated in the supersonic acceleration section 3, the maximum mach number can reach ma2.6, and the interaction between the detonation wave and the supersonic incoming flow forms an obvious wave system structure, which indicates that the configured combustion chamber 5 has the necessary condition for carrying out optical measurement.
In general, the disc-shaped rotary detonation combustor 5 provided by the scheme can realize the stable organization of rotary detonation waves, the rotary detonation back pressure and incoming flow interact to form an obvious wave system structure, and the calculation result verifies the rationality of the technical scheme, so that a foundation is laid for the next step of carrying out supersonic flow field optical measurement.
Example 2
This example differs from example 1 only in that: in the embodiment, a reflective schlieren measurement system is adopted, a schematic diagram of a light path arrangement is shown in fig. 8, a light source 11 is imaged at a slit by a lens 12 to form a slit light source 11, the slit light source 11 is located at a focus of a first concave reflector 13, the slit light source 11 is reflected by the first concave reflector 13 to become parallel light, then the direction of the parallel light is changed by a first plane reflector 14, the parallel light passes through a non-uniform flow field to be refracted to different degrees, then the light is reflected to a second concave reflector 16 by a second plane reflector 15, a knife edge 17 is located at a focus of the second concave reflector 16, the light reflected by the second concave reflector is cut by a half after passing through the knife edge 17, and the rest enters a high-speed camera 18 to finally realize observation of a flow field.
It can be seen that, because the combustion chamber 5 has a simple configuration, the optical path arrangement is quite conventional when observing the combustion chamber in the test, and no additional design is needed, which indicates that the disk-shaped combustion chamber 5 provided by the utility model has sufficient convenience in optical observation.
The foregoing are merely examples of the present invention and common general knowledge of known specific structures and/or features of the schemes has not been described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.
Claims (5)
1. The utility model provides a can realize rotatory detonation combustion chamber of disc of supersonic velocity flow field observation which characterized in that: the fuel injection combustion chamber comprises two cover plates which are arranged at intervals, a disc-shaped cavity is formed between the two cover plates, an air collecting cavity, a supersonic speed accelerating section, an expanding section and a combustion chamber are sequentially arranged in the cavity from the center to the edge, the thickness of the air collecting cavity is larger than that of the supersonic speed accelerating section, the expanding section is trumpet-shaped, one side with a small opening is connected with the supersonic speed accelerating section, a plurality of fuel spray holes are distributed in the expanding section along the circumferential direction, optical observation windows are arranged on the supersonic speed accelerating section and the combustion chamber, and the optical observation windows are used for schlieren or high-speed shooting optical path arrangement; an air inlet communicated with the air collection cavity is formed in the center of any cover plate, a plurality of lifting lugs are arranged on each cover plate, and the two lifting lugs which correspond to each other are connected through bolts.
2. The disc-shaped rotary detonation combustor capable of realizing supersonic flow field observation according to claim 1, is characterized in that: the cross sections of the supersonic speed accelerating section and the combustion chamber are equal straight sections.
3. The disc-shaped rotary detonation combustor capable of achieving supersonic flow field observation according to claim 1, is characterized in that: and a plurality of fuel spray holes are uniformly distributed on the expansion section of each cover plate along the circumferential direction.
4. The disc-shaped rotary detonation combustor capable of achieving supersonic flow field observation according to claim 3, is characterized in that: two first threaded positioning holes distributed at intervals are formed in the lifting lug of any cover plate, and a second threaded positioning hole which is coaxial with any first threaded positioning hole is formed in the lifting lug of the other cover plate.
5. The disc-shaped rotary detonation combustor capable of realizing supersonic flow field observation according to any one of claims 1-4, characterized in that: a detonation tube is arranged tangentially at the 1/4 flow-direction position of the combustion chamber.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202220152362.2U CN217004537U (en) | 2022-01-20 | 2022-01-20 | Disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation |
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| CN202220152362.2U CN217004537U (en) | 2022-01-20 | 2022-01-20 | Disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114427689A (en) * | 2022-01-20 | 2022-05-03 | 中国空气动力研究与发展中心空天技术研究所 | Disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation |
| CN118067951A (en) * | 2024-04-10 | 2024-05-24 | 吉林大学 | Ultrasonic energetic material detonating device and ultrasonic energetic material detonating method |
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2022
- 2022-01-20 CN CN202220152362.2U patent/CN217004537U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114427689A (en) * | 2022-01-20 | 2022-05-03 | 中国空气动力研究与发展中心空天技术研究所 | Disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation |
| CN114427689B (en) * | 2022-01-20 | 2024-07-12 | 中国空气动力研究与发展中心空天技术研究所 | Disc-shaped rotary detonation combustion chamber capable of realizing supersonic flow field observation |
| CN118067951A (en) * | 2024-04-10 | 2024-05-24 | 吉林大学 | Ultrasonic energetic material detonating device and ultrasonic energetic material detonating method |
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