Multi-swirl combustion device suitable for multi-dimensional optical measurement

Abstract

The present application relates to a kind of combustion chamber systems, specifically relates to a kind of multi-swirl combustion device suitable for multi-dimensional optical measurement, including mutually communicating air inlet cavity and combustion chamber assembly and optical assembly towards combustion chamber assembly;The air inlet cavity is provided with fuel switching hole and gas path switching hole on wall surface;The combustion chamber assembly includes in order communicating rectifier channel, fuel flow channel, combustion cavity and exhaust cavity.Compared with prior art, the present application solves the problem that it is difficult to carry out the optical imaging of ignition flame process under wide altitude condition in prior art, the combustion device of the present application successfully simulates the main flow field characteristics of real aeroengine combustion chamber, can carry out multi-swirl ignition flame mechanism research, and then can provide technical support for the design optimization of aeroengine.

Description

TECHNICAL FIELD

[0001] The present application relates to a combustion chamber system, in particular to a multi-swirl combustion device suitable for multi-dimensional optical measurement. BACKGROUND

[0002] The aero-engine can be considered as the heart of the aircraft, and its importance to the aircraft is self-evident.

[0003] The aero-engine has the problem of high-altitude ignition difficulty, which is mainly caused by the reasons such as thin air, low air pressure, low temperature, and poor fuel atomization quality at high altitude. If the engine is extinguished at high altitude, it is generally necessary to reduce the flight altitude, re-ignite and ascend again, which will greatly endanger the flight safety. Therefore, there is a great demand for widening the high-altitude ignition envelope for any type of aero-engine to improve the safety of high-altitude flight.

[0004] In order to carry out the high-altitude ignition technology research, it is necessary to build a low-temperature and low-pressure (-50℃, 0.4bar) combustion chamber system to simulate the aerodynamic and thermal environment of engine high-altitude re-ignition. However, most of the previous researches on the ignition process are limited to the single-head combustion chamber, and the research on the complete annular combustion chamber ignition and flame coupling process is insufficient.

[0005] In the multi-swirl combustion device disclosed in the previous research, most of the design features mainly include an air inlet mixing cavity, a combustion chamber, an optical window, and related auxiliary devices including an air inlet system, an oil supply system, and an exhaust system. Such multi-head combustion device is usually only suitable for working under normal temperature and pressure flow conditions. In addition, the structure of the combustion device and its supporting components is relatively complex, it is difficult to realize precise optical imaging measurement, and it is more difficult to carry out multi-physical quantity and multi-dimensional synchronous optical measurement research.

[0006] Therefore, it is necessary to design a combustion device that can be used to simulate and study the annular combustion chamber ignition and flame coupling process. SUMMARY

[0007] The purpose of the present application is to provide a multi-swirl combustion device suitable for multi-dimensional optical measurement, which solves the problem of difficult optical imaging of the ignition and flame coupling process under wide altitude conditions in the prior art. The combustion device of the present application successfully simulates the main flow field characteristics of the real aero-engine combustion chamber, can carry out multi-swirl ignition and flame coupling mechanism research, and can provide technical support for the design optimization of aero-engine.

[0008] The purpose of the present application is achieved by the following technical solutions:

[0009] A multi-swirl combustion device suitable for multi-dimensional optical measurement, comprising an air inlet cavity and a combustion chamber assembly in communication with each other, and an optical assembly arranged towards the combustion chamber assembly;

[0010] The air inlet cavity is provided with a fuel adapter hole and an air path adapter hole on the wall surface;

[0011] The combustion chamber assembly comprises a flow straightening channel, a combustion cavity and an exhaust cavity in sequence;

[0012] The flow straightening channel can be provided with multiple groups, which are arranged in parallel in the air inlet cavity and are composed of a fuel flow channel and an air flow channel; one end of the fuel flow channel is connected to the fuel adapter hole through an adapter joint, and the other end is connected to the combustion cavity through a pressure atomizing nozzle; one end of the air flow channel is in communication with the air inlet cavity, and the other end is in communication with the combustion cavity; a flow straightener, a swirler and a bluff body are arranged in the air flow channel in sequence along the airflow direction;

[0013] The combustion cavity is provided with a swirl spray bottom plate, an inner side wall glass and a glass clamping groove; the swirl spray bottom plate is arranged at an upstream position in the combustion cavity, the flow straightening channel passes through the swirl spray bottom plate and is arranged at an upstream position in the combustion cavity; the glass clamping groove is arranged on the opposite side of the swirl spray bottom plate, the inner side wall glass is attached to the side edge of the swirl spray bottom plate and clamped in the glass clamping groove, and the glass clamping groove is provided with a plurality of groove positions; one wall surface of the side wall of the combustion cavity is provided as an ignition side panel, and at least two wall surfaces are provided as outer side wall glasses; the ignition side panel is provided with an igniter mounting hole, and the igniter is assembled in the igniter mounting hole;

[0014] The exhaust cavity is provided with an exhaust gas discharge hole on the wall surface, and the wall surface of the exhaust cavity downstream of the combustion cavity is provided as a downstream bottom wall glass;

[0015] The inner side wall glass, the outer side wall glass and the downstream bottom wall glass are all optical glasses;

[0016] The optical assembly is arranged towards the inside of the combustion cavity through the optical glass.

[0017] Preferably, the combustion chamber assembly further comprises a support frame, which is connected to the swirl spray bottom plate and arranged towards the inside of the air inlet cavity, and the support frame is attached to the inner side wall of the air inlet cavity to support the air inlet cavity.

[0018] Preferably, a plurality of igniter mounting holes are provided on the ignition side panel, which are arranged at any multiple positions at a distance of 1, 2, 3 and 4 times the diameter of the bluff body from the pressure atomizing nozzle, and the ignition position and ignition energy can be optimized by comparing the ignition success probability and ignition flame speed at each position.

[0019] Preferably, the surface of the air inlet cavity is also provided with a measuring hole, and a temperature sensor can be arranged in the measuring hole to monitor the temperature of the air in the air inlet cavity.

[0020] Preferably, the multi-swirl combustion device further comprises a displacement table, the displacement table comprising a Z-axis displacement arm, an X-axis displacement arm and an adapter plate; the X-axis displacement arm is provided with an X-direction sliding rail extending along the X-axis direction, the Z-axis displacement arm is provided with a Z-direction sliding rail extending along the Z-axis direction, the Z-axis displacement arm is slidingly connected in the X-direction sliding rail of the X-axis displacement arm, and the adapter plate is slidingly connected in the Z-direction sliding rail of the Z-axis displacement arm; the adapter plate supports the combustion chamber assembly.

[0021] Further preferably, in the displacement table, the X-axis displacement arm and the Z-axis displacement arm are both precisely driven by servo motors, which can quickly complete the spatial position matching between the combustion chamber assembly and the optical assembly, and can also realize the measurement of multiple physical quantities at different cross sections in the flow field, thereby helping to reconstruct the three-dimensional combustion field in the combustion chamber.

[0022] Preferably, the rectifier is a ring-shaped metal foam copper filled in the air flow channel.

[0023] Preferably, the rectifier is a ring-shaped metal foam copper filled in the air flow channel.

[0024] Preferably, the upstream of the fuel flow channel is limited by a limiting plate arranged in the air inlet cavity.

[0025] Preferably, the inner wall of the exhaust cavity is provided in a sandwich structure, a cooling liquid flow channel is arranged in the sandwich, a cooling liquid communication port is arranged on the surface of the exhaust cavity, and the cooling liquid communication port communicates with the cooling liquid flow channel.

[0026] Preferably, the air inlet cavity and the combustion chamber and the combustion chamber and the exhaust cavity are sequentially connected by flanges, and sealing gaskets are arranged at the connection positions to realize sealing.

[0027] Preferably, the optical assembly comprises but is not limited to a high-frequency optical camera and a laser, and the high-frequency optical camera can further preferably be a high-speed CMOS camera with an image intensifier. The optical assembly can be optically measured by three directions through the multiple side walls provided with optical glass in the combustion chamber assembly, and the supporting assembly structure is simple, can synchronously perform multi-physical quantity and multi-dimensional optical imaging, and is more conducive to understanding the three-dimensional unsteady transient process in the ignition and flame coupling process.

[0028] Preferably, the multi-swirl combustion device can be equipped with a controller to further realize automatic triggering, such as by connecting the controller to the igniter, high-frequency optical camera and laser as a controller, respectively, to control the triggering timing between the igniter, high-frequency camera and laser through the upper computer to complete remote control and automatic ignition and recording.

[0029] The working principle of the present application is as follows:

[0030] The combustion device disclosed by the present application first passes fuel and air into the rectification channel of the intake cavity through the fuel transfer hole and the air transfer hole on the wall surface of the intake cavity, respectively, through the external mass flow controller; then, the air and fuel enter the combustion cavity through the air flow channel and the fuel flow channel, respectively, and the oil-gas mixture near the igniter is discharged by the igniter assembled on the ignition side panel in the combustion cavity to complete ignition, and the exhaust gas generated by combustion enters the exhaust cavity and is discharged from the exhaust hole.

[0031] During the ignition and flame coupling process, the optical assembly that has been calibrated and set can perform multi-physical quantity and multi-dimensional optical measurement of the ignition and flame coupling process from the front, side and bottom of the combustion chamber assembly.

[0032] Compared with the prior art, the present application has the following beneficial effects:

[0033] The present application proposes a multi-swirl ignition and flame coupling basic combustion device with the main flow field characteristics of a real aero-engine combustion chamber, which can be used not only under high-altitude conditions but also under ground conditions, and can realize multi-physical quantity and multi-dimensional synchronous optical imaging, solving the problem of difficult optical imaging of the ignition and flame coupling process under high-altitude conditions, providing technical support for the design and optimization of aero-engines, and being one of the key advanced combustion technologies for aero-engines.

[0034] (1) The multi-swirl combustion device can perform ignition tests under high-altitude conditions through the effective support of the support frame in the intake cavity and the double-cavity design of the combustion cavity, and can meet the test limits of low pressure 0.2bar and low temperature 223K on the basis of ensuring structural strength; the multi-swirl combustion device can be applied to ignition tests and optimization under wide-altitude (from ground to 10km altitude) conditions;

[0035] (2) The ignition side panel is provided with a plurality of different igniter mounting positions, including 1, 2, 3 and 4 times the body diameter downstream of the middle nozzle, and 1, 2, 3 and 4 times the body diameter downstream of the middle of the adjacent two nozzles. By comparing the ignition success probability and the ignition flame speed at each position, the ignition position and ignition energy can be optimized. In addition, the purpose of setting the igniter mounting hole at 1 and 4 times the body diameter downstream of the side nozzle is to prolong the distance of the flame propagation along the circumference, which can more accurately capture the circumferential propagation characteristics of the ignition flame;

[0036] (3) The multi-swirl combustion device can use front, side and bottom angles for optical imaging. Through three-dimensional synchronous optical imaging of multiple physical quantities, the three-dimensional unsteady phenomena in the ignition flame propagation process can be well captured.

[0037] (4) The ignition test under different wall spacing conditions can be realized by adjusting the clamping position of the inner side wall glass in the glass clamping groove in the combustion chamber. The ignition test under different head spacing conditions can be realized by adjusting the spacing distance between the multiple rectifier channels, and finally the spray combustion ignition flame experimental research under different cavity restriction conditions can be realized.

[0038] (5) The multi-swirl combustion device can realize the spatial movement of X and Z axes by means of high-precision servo motor displacement table, which can quickly and efficiently complete the spatial position matching between the combustion chamber assembly and the optical assembly, and can also realize the measurement of multiple physical quantities at different cross sections in the flow field, thereby helping to reconstruct the three-dimensional combustion field in the combustion chamber.

[0039] (6) The fuel flow channel of the multi-swirl combustion device can pass through liquid fuel and gaseous fuel, such as liquid fuel, methane and hydrogen, so that the combustion device can test and simulate existing conventional aircraft engine fuels such as aviation kerosene and biofuels, and can also test and simulate other oil and flammable gases that may be used as fuel under actual conditions, providing effective assistance for the development of aircraft engines and the search for new fuels. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 The structure diagram of the multi-swirl combustion device of the present application is shown in the figure;

[0041] Figure 2 The structure diagram of the intake cavity is shown in the figure;

[0042] Figure 3 The structure diagram of the combustion chamber assembly is shown in the figure;

[0043] Figure 4 The cross-sectional structure diagram of the combustion chamber assembly is shown in the figure;

[0044] Figure 5 The structure diagram of the displacement table is shown in the figure;

[0045] Figure 6 Structure diagram of an ignition side panel;

[0046] Figure 7 Structure diagram of another ignition side panel;

[0047] In the figure: 1 - air inlet cavity; 2 - displacement table; 3 - combustion chamber assembly; 4 - fuel switching hole; 5 - measuring hole; 6 - air path switching hole; 7 - support frame; 8 - rectifier channel; 9 - pressure atomizing nozzle; 10 - swirl spray bottom plate; 11 - combustion cavity; 12 - inner side wall glass; 13 - cooling liquid communication port; 14 - tail gas discharge hole; 15 - downstream bottom wall glass; 16 - exhaust cavity; 17 - Z-axis displacement arm; 18 - X-axis displacement arm; 19 - switching plate; 20 - ignition side panel; 21 - high-frequency optical camera; 22 - first igniter mounting hole; 23 - second igniter mounting hole; 24 - third igniter mounting hole; 25 - fourth igniter mounting hole; 26 - fifth igniter mounting hole; 27 - sixth igniter mounting hole; 28 - seventh igniter mounting hole; 29 - eighth igniter mounting hole; 30 - ninth igniter mounting hole; 31 - tenth igniter mounting hole; 32 - rectifier; 33 - oil inlet hole; 34 - limiting plate; 35 - switching joint; 36 - fuel flow channel; 37 - air flow channel; 38 - swirler; 39 - air inlet hole; 40 - bluff body; 41 - glass clamp; 42 - outer side wall glass; 43 - glass clamping groove; 44 - cooling liquid flow channel; 45 - downstream bottom wall sealing gasket; 46 - downstream bottom wall cover plate; 47 - downstream polytetrafluoroethylene sealing gasket of combustion cavity; 48 - air inlet cavity cover plate rubber sealing gasket; 49 - air inlet cavity cover plate; 50 - downstream rubber sealing gasket of air inlet cavity. DETAILED DESCRIPTION

[0048] The present application will be described in detail below with reference to the accompanying drawings and specific examples.

[0049] Example 1

[0050] A multi-swirl combustion device suitable for multi-dimensional optical measurement, as shown in Figures 1-7 includes an air inlet cavity 1 and a combustion chamber assembly 3 in communication with each other, and an optical assembly arranged towards the combustion chamber assembly 3;

[0051] The air inlet cavity 1 is provided with a fuel switching hole 4 and an air path switching hole 6 on the wall surface;

[0052] The combustion chamber assembly 3 includes a rectifier channel 8, a combustion cavity 11 and an exhaust cavity 16 in sequence;

[0053] The rectifier channel 8 is provided in multiple sets, arranged parallel to each other inside the intake chamber 1, and consists of a fuel channel 36 and an air channel 37. One end of the fuel channel 36 is connected to the fuel transfer hole 4 through the adapter 35, and the other end is connected to the combustion chamber 11 through the pressure atomizing nozzle 9. One end of the air channel 37 is connected to the intake chamber 1, and the other end is connected to the combustion chamber 11. A rectifier 32, a swirler 38, and a blunt body 40 are arranged sequentially along the airflow direction inside the air channel 37.

[0054] The combustion chamber 11 is provided with a swirling spray base plate 10, an inner sidewall glass 12, and a glass slot 43. The swirling spray base plate 10 is located upstream of the combustion chamber 11, and the rectifier channel 8 passes through the swirling spray base plate 10 and is arranged at intervals upstream of the combustion chamber 11. The glass slot 43 is located on the opposite side of the swirling spray base plate 10 (i.e., downstream of the combustion chamber 11). The inner sidewall glass 12 is attached to the side of the swirling spray base plate 10 and is engaged in the glass slot 43. The glass slot 43 has several slots. In the sidewall of the combustion chamber 11, one wall surface is provided as an ignition side panel 20, and at least two walls are provided as outer sidewall glass 42. The ignition side panel 20 has an igniter mounting hole, and the igniter is installed in the igniter mounting hole.

[0055] The exhaust chamber 16 has an exhaust gas discharge hole 14 on its wall, and the side of the exhaust chamber 16 located downstream of the combustion chamber 11 is provided as a downstream bottom wall glass 15.

[0056] The inner wall glass 12, the outer wall glass 42, and the downstream bottom wall glass 15 are all optical glass;

[0057] The optical components are positioned facing the interior of the combustion chamber 11.

[0058] More specifically, in this embodiment:

[0059] like Figure 1 As shown, the main body of the multi-swirling combustion device includes an air intake chamber 1, a displacement stage 2, a combustion chamber assembly 3, and an optical component; wherein the air intake chamber 1 and the combustion chamber assembly 3 are interconnected and the air intake chamber 1 is located upstream of the combustion chamber assembly 3, the displacement stage 2 is located below the combustion chamber assembly 3, and the optical component is arranged facing the combustion chamber assembly 3.

[0060] The intake chamber 1 is a hollow shell. One end is fixed to the cover plate of the intake chamber 1 by a flange and sealed at the connection position by the rubber sealing gasket 48 of the intake chamber cover plate. The other end is externally connected to the flange of the combustion chamber assembly 3 (specifically the upper end of the combustion chamber 11) by a flange and sealed at the connection position by the rubber sealing gasket 50 downstream of the intake chamber. The interior of the intake chamber 1 is connected to the combustion chamber assembly 3 through the flow channel 8.

[0061] The wall of the intake cavity 1 is respectively provided with a fuel switching hole 4 (the oil inlet hole 33 as viewed from the inside of the intake cavity 1), a measuring hole 5 and an air path switching hole 6 (the air inlet hole 39 as viewed from the inside of the intake cavity 1), as shown in Figure 2 which the fuel switching hole 4 is connected with an external fuel supply pipeline, the air path switching hole 6 is connected with an external air supply pipeline, and the measuring hole 5 is internally distributed with a temperature sensor for monitoring the air temperature in the intake cavity 1.

[0062] The combustion chamber assembly 3 can be further divided into a support frame 7, a rectifying channel 8, a combustion cavity 11 and an exhaust cavity 16, in which the rectifying channel 8, the combustion cavity 11 and the exhaust cavity 16 are sequentially communicated, as shown in Figure 3 .

[0063] The support frame 7 is fixed to the outside of the combustion cavity 11 and located inside the intake cavity 1; the support frame 7 is in close contact with the inner side wall of the intake cavity 1, and a structure in which multiple support columns intersect multiple cross beams, as shown in Figure 3 , can be preferably used, so that the intake cavity 1 can be effectively supported when low pressure test is performed, and structural damage and collapse can be avoided. By adopting the support frame 7, when the downstream vacuum pump works, the inside of the intake cavity 1 presents a "negative pressure" state, and the wall of the intake cavity 1 will be deformed, at this time the support frame 7 will be closely combined with the deformed inner wall of the intake cavity 1, and the intake cavity 1 can be ensured to be within a controllable deformation range, and its low pressure limit can be close to 0.2 bar, which meets the design requirements.

[0064] The rectifying channel 8 in the embodiment is provided with three, forming a three-swirl combustion device, as shown in Figure 4The rectifier channels 8 are arranged parallel to each other and spaced apart inside the air intake chamber 1. Their downstream ends extend into the combustion chamber 11 and are mounted on the swirl spray base plate 10 (which can be connected by screws and sealed with rubber O-rings). In other embodiments, the number and spacing of the rectifier channels 8 can be increased or decreased as needed to simulate the required quantity and demand. The rectifier channel 8 has a concentric cylindrical structure. The inner side is the fuel flow channel 36 through which fuel passes, and the outer side is the air flow channel 37 through which air passes. One end of the fuel flow channel 36 is connected to the fuel transfer hole 4 through the adapter 35. The external fuel supply line supplies fuel to the fuel flow channel 36 through the fuel transfer hole 4. A mass flow meter is designed on the fuel supply line to control the flow rate. The other end of the fuel flow channel 36 is a pressure atomizing nozzle 9 that extends into the combustion chamber 11. One end of the air flow channel 37 is directly connected to the air intake chamber 1, and the other end is directly connected to the combustion chamber 11. Inside the air flow channel 37, along the direction of airflow, there are rectifiers 32, swirlers 38, and blunt bodies 40 arranged in sequence. The rectifier 32 is formed by annular metal foam copper. The swirler 38 is designed at 45° (when viewed from upstream of the combustion chamber 11, the airflow rotates clockwise after passing through the swirler 38). The blunt body 40 is a circular metal blunt body 40. In addition, the fuel flow channel 36 is limited upstream by a limiting plate 34 provided in the intake chamber 1. Preferably, the limiting plate 34 of the flow channel can be detachable, such as snap-fit ​​or plug-in, so that the limiting plate 34 can be selected with a suitable specification to match the spacing of the flow channel 8.

[0065] In addition to the aforementioned swirling spray base plate 10, the combustion chamber 11 also includes an inner wall glass 12, a glass slot 43, and a glass clamp 41. The swirling spray base plate 10, as described above... Figure 4 In the middle part of the combustion chamber 11, located on the upstream wall, there is a boss. The ends of the flow channel 8 are evenly spaced inside the boss. The inner wall glass 12 is attached to the side of the boss. One end is engaged in the groove of the glass slot 43 (the glass slot 43 is located on the opposite side of the swirl spray base plate 10), and the other end is engaged and positioned with one end of the glass clamp 41 (the end of the glass clamp 41 is sealed to the swirl spray base plate 10 by a rubber gasket). The other end of the glass clamp 41 abuts against the side wall of the combustion chamber 11, so that the inner wall glass 12 is limited. The swirl spray base plate 10 is also detachably installed in the combustion chamber 11, and different opening intervals can be replaced to adapt to the flow channels 8 with different intervals; the glass slot 43 is provided with several slots, so that the inner wall glass 12 can be adjusted to lock in position; therefore, the combustion chamber 11 can simulate ignition tests under different head spacing and different wall spacing, and thus optimize the spray flame ignition and flame connection process under different chamber constraints.

[0066] The top surface of combustion chamber 11 (with) Figure 4 Direction and combination Figure 1As shown by way of example, the side face, i.e. the upper face of the combustion chamber 11, is provided with an outer side wall glass 42 as a side wall, so that the optical assembly can observe and record the situation in the combustion chamber 11 through the outer side wall glass 42 and the inner side wall glass 12. In addition, the front face of the combustion chamber 11 (facing outward, as shown by way of example) is also provided with an outer side wall glass 42. As described above, the inner side wall glass 12 and the outer side wall glass 42 are both made of optical glass, so as to provide more accurate optical diagnosis effect. Based on the double-wall structure of the combustion chamber 11, the combustion reaction is limited to the inner glass wall, which can reduce the influence of the trace leakage of the outer glass wall under the condition of extreme "negative pressure" on the experiment, further improve the accuracy of the experiment, basically solve the influence of the air tightness of the device on the ignition process under the condition of low-pressure environment, and at the same time, improve the reliability of the ignition test under the condition of low-temperature, low-pressure and high-altitude airflow. Figure 4 direction and in combination Figure 1 As shown by way of example, the front face is the outward side) is also provided with an outer side wall glass 42. As described above, the inner side wall glass 12 and the outer side wall glass 42 are both made of optical glass, so as to provide more accurate optical diagnosis effect. Based on the double-wall structure of the combustion chamber 11, the combustion reaction is limited to the inner glass wall, which can reduce the influence of the trace leakage of the outer glass wall under the condition of extreme "negative pressure" on the experiment, further improve the accuracy of the experiment, basically solve the influence of the air tightness of the device on the ignition process under the condition of low-pressure environment, and at the same time, improve the reliability of the ignition test under the condition of low-temperature, low-pressure and high-altitude airflow.

[0067] The side face of the combustion chamber 11 is provided with an ignition side panel 20, which is assembled to Figure 1 and Figure 4 the rear side of the combustion chamber 11; as shown by way of example in Figure 6 and 7 The ignition side panel 20 is provided with a plurality of ignition device mounting holes at different positions, for assembling ignition devices, so as to realize the optimization of the ignition position and the ignition energy by comparing the ignition success probability and the ignition flame propagation speed at each position. Specifically, as shown by way of example in Figure 6 , the third ignition device mounting hole 24 and the fourth ignition device mounting hole 25 are respectively arranged at 2 times and 4 times the diameter of the blunt body 40 at the middle nozzle, the fifth ignition device mounting hole 26 and the sixth ignition device mounting hole 27 are respectively arranged at 1 times and 4 times the diameter of the blunt body 50 at the side nozzle, and the first ignition device mounting hole 22 and the second ignition device mounting hole 23 are respectively arranged at 3 times and 1 times the diameter of the blunt body 50 between the adjacent nozzles, and the total number of the ignition device mounting holes is 8; or, as shown by way of example in Figure 7 , the seventh ignition device mounting hole 28 and the eighth ignition device mounting hole 29 are respectively arranged at 1 times and 3 times the diameter of the blunt body 50 at the middle nozzle, and the ninth ignition device mounting hole 30 and the tenth ignition device mounting hole 31 are respectively arranged at 2 times and 4 times the diameter of the blunt body 50 between the adjacent nozzles, and the total number of the ignition device mounting holes is 6. The fifth ignition device mounting hole 26 and the sixth ignition device mounting hole 27 arranged at 1 times and 4 times the diameter of the blunt body 50 at the side nozzle can prolong the distance of the flame propagation along the circumference, so as to help more accurately capture the circumferential propagation characteristics of the ignition flame.

[0068] The combustion cavity 11 is fixedly connected with the exhaust cavity 16 at the downstream end through a flange, and structural sealing is realized through a PTFE sealing gasket 47 at the downstream of the combustion cavity. The exhaust cavity 16 is provided with an exhaust gas outlet hole 14 on the surface thereof, which can be used for discharging the exhaust gas generated by combustion. The exhaust cavity 16 can also be externally connected to a vacuum pump to measure the low pressure condition and discharge the exhaust gas. The exhaust cavity 16 is provided with a downstream bottom wall glass 15 at the downstream position, which is fixedly assembled through a downstream bottom wall cover plate 46. The downstream bottom wall glass 15 adopts a double gasket sealing form, and the downstream bottom wall sealing gasket 45 and the graphite gasket pre-installed in the downstream bottom wall cover plate 46 jointly form a seal, so as to further ensure the air tightness of the device under low pressure condition, and make the stress of the local edge of the glass uniform. In addition, the outer side wall glass 42 of the combustion cavity 11 can also adopt a similar double sealing form to improve the sealing performance. The downstream bottom wall glass 15 is also optical glass, which cooperates with the glass on the front surface and the top surface of the combustion cavity 11 to set the optical assembly at the position of the optical glass and face the inside of the combustion cavity 11, so as to realize optical imaging of ignition and combustion in the combustion cavity 11 at three angles. The wall surface of the exhaust cavity 16 adopts a sandwich structure design form, and the inside is designed as a cooling liquid flow channel 44. The surface of the exhaust cavity 16 is provided with a cooling liquid communication port 13. The external cooling circulating pipeline can access the cooling liquid flow channel 44 through the cooling liquid communication port 13 to realize the circulating flow of the cooling liquid.

[0069] When the air fills the air inlet cavity 1 through the air inlet hole 39, it is first rectified by the rectifier 32, then flows through the air flow channel 37, enters the combustion cavity 11 after the cyclone 38, and reacts with the fuel sprayed by the pressure atomizing nozzle 9. The combustion exhaust gas first enters the exhaust cavity 16, and finally exits the combustion chamber assembly 3 through the exhaust gas outlet hole 14.

[0070] As shown in Figure 5 , it is a displacement table 2 in the multi-swirl combustion device, which is composed of an X-axis displacement arm 18, a Z-axis displacement arm 17 and an adapter plate 19. The X-axis displacement arm 18 is provided with an X-direction sliding rail extending along the X-axis direction, and the Z-axis displacement arm 17 is slidingly assembled in the X-direction sliding rail, so that the Z-axis displacement arm 17 can slide in the X-direction. The Z-axis displacement arm 17 is provided with a Z-direction sliding rail extending along the Z-axis direction, and the adapter plate 19 is slidingly assembled in the Z-direction sliding rail, so that the adapter plate 19 can slide in the Z-direction. The adapter plate 19 supports the combustion chamber assembly 3, specifically supports the flange connection of the combustion cavity 11 and the two side cavities. Figure 1The high-precision servo motor is used to realize the precise and rapid space movement of the combustion chamber assembly 3 in the X direction and the Z direction, so as to quickly complete the space position matching among the combustion chamber assembly 3, the high-frequency optical camera 21 and the laser, realize the optical measurement of the ignition and flame propagation process, and also realize the multi-physical quantity measurement at different cross sections in the flow field, thereby helping to reconstruct the three-dimensional combustion field in the combustion chamber 11.

[0071] The optical assembly used in the multi-swirl combustion device includes but is not limited to the high-frequency optical camera 21 and the laser, and the high-frequency optical camera 21 is preferably a high-speed CMOS camera with an image intensifier. The optical assembly can be used for optical measurement from the front surface (through the outer side wall glass 42), the top surface (through the outer side wall glass 42 and the inner side wall glass 12) and the downstream bottom surface (through the downstream bottom wall glass 15) of the combustion chamber 11. Due to the simple structure of the matched assembly, the multi-physical quantity and multi-dimensional optical imaging can be simultaneously performed, which is more conducive to understanding the three-dimensional unsteady transient process in the ignition and flame propagation process.

[0072] Further, the multi-swirl combustion device can be used in cooperation with a control system. The control system is electrically connected with the switch of the spark igniter arranged in the igniter mounting hole, the control module built in the high-frequency optical camera 21 and the switch of the laser. In this embodiment, the upper computer is used to control the trigger timing among the igniter, the high-frequency optical camera 21 and the laser, so as to complete the remote control and automatic measurement.

[0073] The working principle of the embodiment is as follows:

[0074] Firstly, the fuel and air enter the rectifier channel 8 in the air inlet cavity 1 through the fuel transfer hole 4 and the air path transfer hole 6 on the wall surface of the air inlet cavity 1. Then, the air and fuel enter the combustion chamber 11 through the air flow channel 37 and the fuel flow channel 36, respectively, and the oil-gas mixture near the igniter is discharged by the igniter arranged on the ignition side panel 20 in the combustion chamber 11, so as to complete the ignition. The exhaust gas generated by the combustion enters the exhaust cavity 16 and is discharged from the device through the exhaust hole 14.

[0075] During the ignition and flame propagation process, the optical assembly which has been calibrated and set can be used for multi-physical quantity and multi-dimensional optical measurement of the ignition and flame propagation process from the front surface, the side surface and the bottom surface.

[0076] The foregoing description of the embodiments has been presented for the purpose of illustration and description. It is not intended to be exhaustive or to limit the application to the precise form disclosed. Modifications and variations are possible in light of the above teachings or can be acquired from practice of the application. As well, the description is presented in the context of the preferred embodiments as a number of alternatives. It is not intended to limit the application to the precise form described.

Claims

1. A multi-swirl combustion device suitable for multidimensional optical measurements, characterized by, The application relates to a combustion chamber assembly and an optical assembly. The air inlet cavity (1) is provided with fuel switching holes (4) and air path switching holes (6) on the wall surface. The combustion chamber assembly (3) comprises rectifier channels (8), combustion cavities (11) and exhaust cavities (16) which are sequentially communicated. The rectifier channels (8) are arranged in the air inlet cavity (1) in parallel and are composed of fuel flow channels (36) and air flow channels (37); one end of the fuel flow channel (36) is connected with the fuel switching hole (4) through a switching joint (35), and the other end is communicated with the combustion cavity (11) through a pressure atomizing nozzle (9); one end of the air flow channel (37) is communicated with the air inlet cavity (1), and the other end is communicated with the combustion cavity (11); a rectifier (32), a cyclone device (38) and a bluff body (40) are sequentially arranged in the air flow channel (37). The combustion cavity (11) is provided with a cyclone spraying bottom plate (10), an inner side wall glass (12) and a glass clamping groove (43); the cyclone spraying bottom plate (10) is arranged at an upstream position in the combustion cavity (11); the rectifier channel (8) penetrates through the cyclone spraying bottom plate (10) and is arranged at the upstream of the combustion cavity (11) at intervals; the glass clamping groove (43) is arranged at the opposite side of the cyclone spraying bottom plate (10); the inner side wall glass (12) is attached to the side edge of the cyclone spraying bottom plate (10) and is clamped in the glass clamping groove (43); the glass clamping groove (43) is provided with a plurality of groove positions; a side wall of the combustion cavity (11) is provided with an ignition side panel (20) and at least two outer side wall glasses (42); an igniter mounting hole is formed in the ignition side panel (20), and an igniter is arranged in the igniter mounting hole. The exhaust cavity (16) is provided with an exhaust hole (14) on the wall surface; a downstream bottom wall glass (15) is arranged on the wall surface of the exhaust cavity (16) at the downstream of the combustion cavity (11). The inner side wall glass (12), the outer side wall glass (42) and the downstream bottom wall glass (15) are all optical glasses. The optical assembly is arranged in the combustion cavity (11) through the optical glass.

2. A multi-swirl combustion apparatus suitable for multi-dimensional optical measurements according to claim 1, wherein The combustion chamber assembly (3) further comprises a support frame (7) which is connected to the cyclone spraying bottom plate (10) and is arranged towards the inside of the air inlet cavity (1); the support frame (7) is attached to the inner side wall of the air inlet cavity (1) to support the air inlet cavity (1).

3. The multi-swirl combustion apparatus for multi-dimensional optical measurement according to claim 1, wherein A plurality of igniter mounting holes are formed in the ignition side panel (20) and are arranged at any positions which are 1 times, 2 times, 3 times and 4 times the diameter of the bluff body (40) away from the pressure atomizing nozzle (9).

4. The multi-swirl combustion apparatus for multi-dimensional optical measurement according to claim 1, wherein The air inlet cavity (1) is further provided with a measuring hole (5) in which a temperature sensor is arranged to monitor the temperature of the air in the air inlet cavity (1).

5. The multi-swirl combustion apparatus for multi-dimensional optical measurements of claim 1, wherein The multi-swirl combustion device further comprises a displacement platform (2), the displacement platform (2) comprises a Z-axis displacement arm (17), an X-axis displacement arm (18) and an adapter plate (19); the X-axis displacement arm (18) is provided with an X-direction sliding rail extending along the X-axis direction, the Z-axis displacement arm (17) is provided with a Z-direction sliding rail extending along the Z-axis direction, the Z-axis displacement arm (17) is slidingly connected in the X-direction sliding rail of the X-axis displacement arm (18), and the adapter plate (19) is slidingly connected in the Z-direction sliding rail of the Z-axis displacement arm (17); the adapter plate (19) supports the combustion chamber assembly (3).

6. The multi-swirl combustion apparatus for multi-dimensional optical measurements of claim 1, wherein The rectification channel (8) is a concentric cylindrical structure, the fuel flow channel (36) is located at the inner side, and the air flow channel (37) is wrapped at the outer side.

7. A multi-swirl combustion apparatus suitable for multi-dimensional optical measurements according to claim 6, wherein The rectifier (32) is a ring-shaped metal foam copper filled in the air flow channel (37).

8. A multi-swirl combustion apparatus suitable for multi-dimensional optical measurements according to claim 6, wherein The upstream of the fuel flow channel (36) is limited by the limiting plate (34) arranged in the air inlet cavity (1).

9. The multi-swirl combustion apparatus for multi-dimensional optical measurements of claim 1, wherein, The inner wall of the exhaust cavity (16) is provided in a sandwich structure, the cooling liquid flow channel (44) is arranged in the sandwich, the surface of the exhaust cavity (16) is provided with a cooling liquid communication port (13), and the cooling liquid communication port (13) communicates with the cooling liquid flow channel (44).

10. The multi-swirl combustion apparatus for multi-dimensional optical measurements of claim 1, wherein, The air inlet cavity (1) and the combustion cavity (11) and the combustion cavity (11) and the exhaust cavity (16) are sequentially connected through flanges, and sealing gaskets are arranged at the connection positions to realize sealing.

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