Medium and large scale scramjet engine and relay ignition method thereof

Abstract

The invention belongs to the field of medium-large-scale scramjet engines, and particularly relates to a medium-large-scale scramjet engine and a relay ignition method thereof. The medium-large-scale scramjet engine comprises a combustion chamber, an ignition device I and an ignition device II; at least one concave cavity is formed in the combustion chamber, the two ignition devices are arranged on the same concave cavity, the ignition device I is arranged on the inner wall of the middle stream of the concave cavity, and the ignition device II is arranged on the inner wall of the downstream of the concave cavity; when the pre-injection pressure of the fuel injection hole in the upstream of the ignition device in the combustion chamber is balanced, the ignition device I starts to excite work, and after the set time, the ignition device II starts to excite work. On the basis of the technical scheme of an existing scramjet engine, relay type ignition is conducted by introducing the two ignition devices, the arrangement positions of the two ignition devices are matched, and the problem that initial fire cores and initial flames formed by a single ignition device in a medium-large-scale engine cannot be spread to the main stream of a combustion chamber is solved; and reliable ignition is realized.

Description

Technical Field

[0001] The present invention belongs to the field of medium and large scale scramjet engines, and in particular relates to a medium and large scale scramjet engine and a relay ignition method thereof. Background Art

[0002] At present, medium and large-scale scramjet engines can only rely on standard igniters to achieve forced ignition. However, due to reasons such as engine structure thermal protection, it is not possible to increase the number of igniters to increase the ignition energy (the ignition schemes currently used in medium and large-scale engines generally use two igniters, and the increase in the number of igniters mentioned here refers to >2). This results in insufficient ignition energy for the current standard igniters used in medium and large-scale scramjet engines, and it is easy for the initial flame after ignition to fail to effectively develop into a global flame.

[0003] There are very few reports on medium and large scale scramjet engines in the prior art, especially a lack of research on how to achieve reliable ignition in medium and large scale scramjet engines.

[0004] The closest prior art is the patent "A method and device for promoting the start-up and ignition of a scramjet engine" (application number: 202010829851.2), which discloses a method for ignition and starting of a scramjet engine. This patent is to vertically inject an air jet on one side of the inner wall of the flame stabilizer to generate a shock wave train structure, thereby affecting the thermodynamic parameters of the flow field, increasing the static pressure and static temperature in the flow field and reducing the speed, promoting efficient mixing of fuel and air, and thus achieving reliable ignition and starting of the scramjet engine. However, their research uses 30% of the air flow at the inlet of the combustion chamber to generate downstream air jets, which has a large loss of combustion performance in the combustion chamber; and this method has only been preliminarily verified in a model engine and is not suitable for medium and large-scale scramjet engines.

[0005] Therefore, there is a lack of existing technical support for designing a method to achieve reliable ignition in medium to large scale scramjets. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a medium-to-large scale scramjet engine which can realize reliable ignition and a relay ignition method thereof.

[0007] The present invention provides a medium-to-large scale scramjet engine, comprising a combustion chamber and two ignition devices, wherein the two ignition devices are ignition device I and ignition device II; At least one concave cavity is arranged in the combustion chamber, and the two ignition devices are arranged on the same concave cavity, the ignition device I is arranged on the inner wall of the midstream of the concave cavity, and the ignition device II is arranged on the inner wall of the downstream of the concave cavity; When the pre-injection pressure of the fuel injection hole upstream of the ignition device in the combustion chamber is balanced, the ignition device I starts to ignite and work, and after a set time, the ignition device II starts to ignite.

[0008] Furthermore, the concave cavities are provided with more than two; The two ignition devices are arranged on the most downstream cavity.

[0009] Furthermore, the concave cavity is provided with two, and the two concave cavities are respectively a primary concave cavity and a secondary concave cavity; The two ignition devices are arranged on the secondary cavity.

[0010] Furthermore, the ratio of the distance of the ignition device I from the front edge of the secondary cavity to the height of the flow channel at the front edge of the primary cavity is 2:1; The ratio of the distance from the position of the ignition device II to the flow direction of the trailing edge of the secondary cavity to the height of the flow channel at the leading edge of the primary cavity is 1:1.

[0011] Furthermore, the upstream section of the first-stage concave cavity is provided with an upstream injection hole of the first-stage concave cavity fuel injection section, and the upstream section of the second-stage concave cavity is provided with an upstream injection hole of the second-stage concave cavity fuel injection section.

[0012] Furthermore, the upstream injection hole of the first-stage concave cavity fuel injection section is a hot oil injection hole; The upstream injection hole of the secondary cavity fuel injection section is a cold oil injection hole.

[0013] Furthermore, the set time is positively correlated with the Mach number of the aircraft.

[0014] Furthermore, when the Mach number of the aircraft is Mach 4, the set time is 20ms; When the Mach number of the aircraft is Mach 5, the set time is 40ms; When the Mach number of the aircraft is Mach 6, the set time is 50ms; When the Mach number of the aircraft is Mach 7, the set time is 60ms.

[0015] Furthermore, the ignition device is one of a solid powder igniter, a concentrated spark plug discharge igniter or a sliding arc discharge plasma igniter.

[0016] The present invention also provides a medium-to-large scale scramjet engine relay ignition method, using the medium-to-large scale scramjet engine as claimed in the claim, comprising the following steps: S1, the fuel injection hole upstream of the ignition device in the combustion chamber begins to inject fuel; S2, when the pre-injection pressure of the fuel injection hole is balanced, which is recorded as time t0, the ignition device I starts to ignite; S3, according to the flight Mach number of the aircraft, after a set time after t0, the ignition device II starts to ignite and work, realizing the relay combustion of the initial flame and forming a global flame.

[0017] The beneficial effect of the present invention is that, on the basis of the existing technical solution of scramjet engines, the present invention can solve the problem that the initial fire core and the initial flame formed by a single ignition device in a medium-to-large-scale engine cannot propagate to the mainstream of the combustion chamber by introducing two ignition devices for relay ignition, and coordinating the arrangement positions of the two ignition devices. Specifically, when the initial flame formed by the ignition device I in the concave cavity propagates to the throat position of the concave cavity, it can be effectively connected and relayed by the energy generated by the ignition device II downstream of the concave cavity, and then it can develop into a global flame faster, realizing reliable ignition of medium-to-large-scale scramjet engines, and effectively improving the ignition robustness of cross-scale scramjet engines. In addition, compared with the existing method of using incoming air to enhance the flame, the present invention has the advantages of being applicable to the serialization of engine scales and having no loss of engine performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Attached Figure 1 This is one of the structural schematic diagrams of the medium-to-large scale scramjet engine in the present invention; Attached Figure 2 A schematic diagram of the dimensions of a medium-to-large scale scramjet engine in the present invention; Attached Figure 3 This is the second structural schematic diagram of the medium-to-large scale scramjet engine in the present invention; Attached Figure 4 A curve diagram showing the change of the combustion chamber wall pressure over time obtained by igniting a large-scale scramjet engine by the relay ignition method of the present invention; Attached Figure 5 The graph is a graph showing the change of the combustion chamber wall pressure over time obtained by ignition using the prior art ignition method.

[0019] In the figure: 100-combustion chamber; 200-ignition device I; 300-ignition device II; 1-isolation section; 2-concave section; 2-1-first-stage concave fuel injection section; 2-2-first-stage concave; 2-3-second-stage concave fuel injection section; 2-4-second-stage concave; 3-expansion section; 4-first-stage concave fuel injection section upstream injection hole; 5-second-stage concave fuel injection section upstream injection hole; l0- length of scramjet combustion chamber; l1- length of isolation section; l2- length of cavity section; l3- length of expansion section; l21- length of fuel injection section of primary cavity; l22- length of primary cavity; l23- length of fuel injection section of secondary cavity; l24- length of secondary cavity; d11- height of inlet flow channel of isolation section; d12- height of outlet flow channel of isolation section; d21- height of leading edge flow channel of primary cavity; d22- height of trailing edge flow channel of primary cavity; d23- height of leading edge flow channel of secondary cavity; d24- height of trailing edge flow channel of secondary cavity; d25- height of front wall of primary cavity; d26- height of front wall of secondary cavity; d3- height of outlet flow channel of expansion section; α1- inclination angle of rear wall of primary cavity; α2- inclination angle of rear wall of secondary cavity; dJ1-the height of the transverse flow channel at the upstream injection hole of the first-stage concave cavity fuel injection section; dJ2-the height of the transverse flow channel at the upstream injection hole of the second-stage concave cavity fuel injection section; lJ1-the flow distance from the upstream injection hole of the first-stage concave cavity fuel injection section to the leading edge of the first-stage concave cavity; lJ2-the flow distance from the upstream injection hole of the second-stage concave cavity fuel injection section to the leading edge of the second-stage concave cavity; lig1-the flow distance from the position of the ignition device I to the leading edge of the second-stage concave cavity; lig2-the flow distance from the position of the ignition device II to the trailing edge of the second-stage concave cavity. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0022] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0025] The engine scale described in the present invention is based on the flow rate of the scramjet engine of the X-51A hypersonic aircraft, and a medium-to-large-scale scramjet engine is defined as 2 to 10 times the flow rate of the engine.

[0026] As attached Figure 1 -Attached Figure 3 As shown, the present invention provides a medium-to-large scale scramjet engine, comprising a combustion chamber 100 and two ignition devices, the two ignition devices being an ignition device I 200 and an ignition device II 300; At least one concave cavity is arranged in the combustion chamber 100, and the two ignition devices are arranged on the same concave cavity, the ignition device I 200 is arranged on the inner wall of the midstream of the concave cavity, and the ignition device II 300 is arranged on the inner wall of the downstream of the concave cavity; When the pre-injection pressure of the fuel injection hole upstream of the ignition device in the combustion chamber 100 is balanced, the ignition device I 200 starts to ignite, and after a set time, the ignition device II 300 starts to ignite.

[0027] Based on the existing scramjet engine technical solutions, the present invention can solve the problem that the initial fire kernel and the initial flame formed by a single ignition device in a medium and large-scale engine cannot reach the mainstream of the combustion chamber by introducing two ignition devices for relay ignition and coordinating with the arrangement positions of the two ignition devices. Specifically, when the initial flame formed by the ignition device I 200 in the cavity propagates to the throat position of the cavity, it can be effectively connected and relayed by the energy generated by the downstream ignition device II 300 in the cavity, and then can develop into a global flame faster, realizing reliable ignition of the medium and large-scale scramjet engine and effectively improving the ignition robustness of the cross-scale scramjet engine. In addition, compared with the existing method of enhancing the flame by the oncoming air, the present invention has the advantages of being applicable to a serialized engine scale and having no loss to the engine performance.

[0028] In one embodiment, two or more cavities are provided, that is, the present invention is applicable to a single-cavity or multi-cavity combustion chamber configuration; For the multi-cavity combustion chamber configuration, the specific setting of the two ignition devices in which cavity is related to the selection of the ignition state point. Preferably, the two ignition devices are arranged on the most downstream cavity, because for the medium and large-scale scramjet engine, downstream cavity ignition is an optimized scheme obtained through multiple tests, which can effectively improve the ignition probability. For the single-cavity combustion chamber configuration, the ignition device is arranged in the single cavity.

[0029] In a specific embodiment, two cavities are provided, and the two cavities are the primary cavity 2-2 and the secondary cavity 2-4 respectively; The two ignition devices are arranged on the secondary cavity 2-4.

[0030] In this embodiment, the scramjet engine combustion chamber 100 includes two cavities. The primary cavity 2-2 is mainly used for ram combustion organization at a high oncoming Mach number (Ma5-6), and the secondary cavity 2-4 is mainly used for ram combustion organization at a low oncoming Mach number (Ma3-5). Correspondingly, the primary cavity injection section 2-1 is responsible for fuel injection into the primary cavity 2-2, and the secondary cavity injection section 2-3 is responsible for fuel injection into the secondary cavity 2-4. In this embodiment, the长深 ratio range of the primary cavity 2-2 is 6 < l22 / d25 < 8, preferably 7, and the长深 ratio range of the secondary cavity 2-4 is 4 < l24 / d26 < 6, preferably 5. Such a setting can effectively promote fuel mixing while also making the ignition effect reach an ideal state. The inclination angles of the rear wall surfaces of both the primary cavity and the secondary cavity are 45°.

[0031] In the high Mach number cruising state described in this embodiment, the ratio of the height of the secondary cavity trailing edge flow channel to the height of the inlet duct entrance should satisfy 1.25≤d24 / d11≤1.50, preferably 1.4; in the low Mach number and high equivalence ratio cruising state required for operation, the ratio of the height of the primary cavity trailing edge flow channel to the height of the inlet duct entrance should satisfy 1.15≤d22 / d11≤1.25, preferably 1.2. This arrangement can avoid the adverse effects of excessive flow channel congestion on engine performance as much as possible.

[0032] Preferably, the upstream section of the first-stage concave cavity 2-2 is provided with an upstream injection hole 4 of the first-stage concave cavity fuel injection section, and the upstream section of the second-stage concave cavity is provided with an upstream injection hole 5 of the second-stage concave cavity fuel injection section. By arranging the upstream injection hole 4 of the first-stage concave cavity fuel injection section and the upstream injection hole 5 of the second-stage concave cavity fuel injection section, a wide range of engine operation can be achieved. In the ignition stage, the upstream injection hole 5 of the second-stage concave cavity fuel injection section is used to inject fuel, and in the engine cruising stage, according to different flight conditions, the upstream injection hole 4 of the first-stage concave cavity fuel injection section can also inject fuel to match different incoming flow conditions.

[0033] The transverse flow channel height dJ1 at the upstream injection hole of the first-stage concave cavity fuel injection section described in this embodiment is mainly determined by the thermal throat of the cruising state Ma=6~7; the transverse flow channel height dJ2 at the upstream injection hole of the second-stage concave cavity fuel injection section is mainly determined by the thermal throat of the cruising state Ma=4~5. The expansion angle of the inclined wall (the expansion angle of the expansion section wall) described in the present invention ranges from 1.5° to 3.5°, preferably 2°. The flow direction distance lJ1 of each injection hole of the first-stage concave cavity fuel injection section from the leading edge of the first-stage concave cavity and the flow direction distance lJ2 of each injection hole of the second-stage concave cavity fuel injection section from the leading edge of the second-stage concave cavity are calculated by reverse calculation based on the expansion angle, and are not subject to key constraints. This calculation method is a prior art and will not be repeated here. The fuel injection holes of the wide-range scramjet engine combustion chamber described in this embodiment are preferably circular holes. Preferably, the upstream injection hole 5 of the secondary cavity fuel injection section is a cold oil injection hole, and the upstream injection hole 4 of the primary cavity fuel injection section is a hot oil injection hole. In the engine ignition stage, the upstream injection hole 5 of the secondary cavity fuel injection section injects cold kerosene for ignition and starting; in the engine cruising stage, since the fuel will exchange heat with the wall before injection, the upstream injection hole 4 of the primary cavity fuel injection section will inject hot kerosene.

[0034] In the present invention, the configuration of the combustion chamber and the concave cavity can be a rectangular cross-section or an axisymmetric circular cross-section. For the rectangular cross-section combustion chamber, the number of the four upstream injection holes of the first-stage concave cavity fuel injection section is preferably 10, and the number of the five upstream injection holes of the second-stage concave cavity fuel injection section is preferably 10. All the injection holes are preferably arranged evenly along the width direction.

[0035] For a circular cross-section combustion chamber, the number of the 4 upstream injection holes of the first-stage concave cavity fuel injection section is preferably 10, and the number of the 5 upstream injection holes of the second-stage concave cavity fuel injection section is preferably 10. All injection holes are preferably arranged evenly in the radial direction.

[0036] The diameter of a single cold oil spray hole is preferably d≤1.6mm, and the diameter of a single hot oil spray hole is preferably d≤5mm. The nozzle configuration of all injection holes is preferably a sonic nozzle, and is arranged perpendicular to the wall at 90°.

[0037] In the present invention, the selection of the distance lig1 from the position of the ignition device I to the front edge of the secondary cavity and the distance lig2 from the position of the ignition device II to the rear edge of the secondary cavity should be selected in combination with the shape, size, flow conditions of the ignition cavity, etc. Preferably, the ratio of the distance lig1 from the position of the ignition device I to the front edge of the secondary cavity to the height d21 of the flow channel at the front edge of the primary cavity is 2:1; the ratio of the distance lig2 from the position of the ignition device II to the rear edge of the secondary cavity to the height d21 of the flow channel at the front edge of the primary cavity is 1:1. This ratio is the optimization result obtained through multiple experiments and can effectively improve the engine ignition performance.

[0038] In one embodiment, the set time is positively correlated with the Mach number of the aircraft.

[0039] Preferably, when the Mach number of the aircraft is Mach 4, the set time is 20ms; When the Mach number of the aircraft is Mach 5, the set time is 40ms; When the Mach number of the aircraft is Mach 6, the set time is 50ms; When the Mach number of the aircraft is Mach 7, the set time is 60ms.

[0040] In one embodiment, the ignition device is one of a solid powder igniter, a concentrated spark plug discharge igniter or a sliding arc discharge plasma igniter. The ignition device 2 can also be used in combination with an air / nitrogen throttling device. In the present invention, the two ignition devices are preferably solid powder igniters. In specific use, the energy duration of the solid powder igniter after excitation is about 500ms, and the energy duration of the concentrated spark plug discharge igniter, the sliding arc discharge plasma igniter, the air / nitrogen throttling device, etc. after excitation is about 500ms.

[0041] The present invention also provides a medium-to-large scale scramjet engine relay ignition method, which is characterized by using the medium-to-large scale scramjet engine, comprising the following steps: S1, the fuel injection hole upstream of the ignition device in the combustion chamber 100 starts to inject fuel; S2, when the pre-injection pressure of the fuel injection hole is balanced, which is recorded as time t0, the ignition device I200 starts to ignite; S3, according to the flight Mach number of the aircraft, after a set time after t0, the ignition device II 300 starts to ignite the work, to achieve relay combustion of the initial flame and form a global flame.

[0042] In a specific embodiment, the specific steps of the medium-to-large scale scramjet engine relay ignition method are: S1, the upstream injection hole 5 of the secondary cavity fuel injection section starts to inject fuel; S2, the pressure sensor detects the moment when the pressure of the upstream injection hole 5 of the secondary cavity fuel injection section stabilizes before injection, which is recorded as time t0, and the ignition device I300 starts to ignite; S3, for ignition under the condition of Mach number of Mach 4, at t0+20ms, the ignition device II300 starts to ignite, realizing the relay combustion of the initial flame and finally forming a global flame; For ignition under the condition of Mach number of Mach 5, at the moment of t0+40ms, the ignition device II300 starts to ignite, realizing the relay combustion of the initial flame and finally forming a global flame; For ignition under the condition of Mach number of Mach 6, at the moment of t0+50ms, the ignition device II300 starts to ignite, realizing the relay combustion of the initial flame and finally forming a global flame; For ignition under the condition of Mach number of Mach 7, at the moment of t0+60ms, the ignition device II300 starts to ignite, realizing the relay combustion of the initial flame and finally forming a global flame.

[0043] Reference Figure 4 and attached Figure 5 The following figure is a curve of the combustion chamber wall pressure changing with time under different ignition methods. Figure 4 For the data obtained by using the ignition method described in this application, Figure 5 The dashed line in the figure represents the ignition time (t0) for the data obtained by using other existing ignition methods. By comparison, it can be seen that the method described in this patent can successfully achieve engine ignition and start-up. The steep increase in the pressure curve indicates that the ignition is successful, and a stable and self-sustaining global flame is formed in the combustion chamber.

[0044] The above is only an embodiment and does not limit the present invention in any way. Any person skilled in the art can use the above disclosed technical contents to make many possible changes, modifications or modifications to the technical solutions of the present invention into equivalent embodiments of equivalent changes without departing from the scope of the technical solutions of the present invention. Therefore, any simple modification, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the scope of protection of the technical solutions of the present invention.

Claims

1. A medium-to-large scale scramjet engine, characterized in that: It comprises a combustion chamber (100) and two ignition devices, the two ignition devices are respectively an ignition device I (200) and an ignition device II (300); At least one concave cavity is arranged in the combustion chamber (100), and the two ignition devices are arranged on the same concave cavity, the ignition device I (200) is arranged on the midstream inner wall of the concave cavity, and the ignition device II (300) is arranged on the downstream inner wall of the concave cavity; When the pre-injection pressure of the fuel injection hole upstream of the ignition device in the combustion chamber (100) is balanced, the ignition device I (200) starts to ignite, and after a set time, the ignition device II (300) starts to ignite.

2. The medium-to-large scale scramjet engine according to claim 1, characterized in that: The concave cavities are provided with more than two; The two ignition devices are arranged on the most downstream cavity.

3. The medium-to-large scale scramjet engine according to claim 1, characterized in that: The concave cavities are provided with two, and the two concave cavities are respectively a primary concave cavity (2-2) and a secondary concave cavity (2-4); The two ignition devices are arranged on the secondary cavity (2-4).

4. The medium-to-large scale scramjet engine according to claim 3, characterized in that: The ratio of the distance from the position of the ignition device I to the front edge of the secondary cavity to the height of the flow channel at the front edge of the primary cavity is 2:1; The ratio of the distance from the position of the ignition device II to the flow direction of the trailing edge of the secondary cavity to the height of the flow channel at the leading edge of the primary cavity is 1:

1.

5. The medium-to-large scale scramjet engine according to claim 4, characterized in that: The upstream section of the primary concave cavity (2-2) is provided with a primary concave cavity fuel injection section upstream injection hole (4), and the upstream section of the secondary concave cavity is provided with a secondary concave cavity fuel injection section upstream injection hole (5).

6. The medium-to-large scale scramjet engine according to claim 5, characterized in that: The upstream injection hole (4) of the first-stage concave cavity fuel injection section is a hot oil injection hole; The upstream injection hole (5) of the secondary cavity fuel injection section is a cold oil injection hole.

7. The medium-to-large scale scramjet engine according to any one of claims 1 to 6, characterized in that: The set time is positively correlated with the Mach number of the aircraft.

8. The medium-to-large scale scramjet engine according to claim 7, characterized in that: When the Mach number of the aircraft is Mach 4, the set time is 20ms; When the Mach number of the aircraft is Mach 5, the set time is 40ms; When the Mach number of the aircraft is Mach 6, the set time is 50ms; When the Mach number of the aircraft is Mach 7, the set time is 60ms.

9. The medium-to-large scale scramjet engine according to any one of claims 1 to 6, characterized in that: The ignition device is one of a solid powder igniter, a concentrated spark plug discharge igniter or a sliding arc discharge plasma igniter.

10. A medium-to-large scale scramjet engine relay ignition method, characterized in that: Using the medium-to-large scale scramjet engine according to any one of claims 1 to 9 comprises the following steps: S1, a fuel injection hole upstream of an ignition device in a combustion chamber (100) starts injecting fuel; S2, when the pre-injection pressure of the fuel injection hole is balanced, which is recorded as time t0, the ignition device I (200) starts to ignite; S3, according to the flight Mach number of the aircraft, after a set time after t0, the ignition device II (300) starts to ignite the flame to achieve relay combustion of the initial flame and form a global flame.

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