The main combustion hole air intake scoop-shaped structure used in the high temperature rise main combustion chamber

Abstract

The present invention discloses a main combustion hole air intake bucket-shaped structure applied to a high-temperature main combustion chamber, comprising a flame tube; a main combustion hole extends from the flame tube, the lower end portion of the rear edge of the main combustion hole tilts inward and folds over to form a bucket-shaped arc surface, and an elliptical arc opening is provided extending from the front edge of the main combustion hole to the bucket-shaped arc surface of the main combustion hole; the central axis of the main combustion hole is perpendicular to the central axis of the flame tube, and a total of four main combustion holes are designed, with two holes arranged crosswise on the upper and lower walls of the flame tube, that is, the lateral jets of the main combustion holes are intertwined. Compared with the traditional simple circular flat hole structure, when the main combustion hole and the mixing hole of the high-temperature main combustion chamber adopt the air intake bucket-shaped structure, the lateral jet formed by the main combustion hole has a stronger effect on the truncation and joint formation of the recirculation zone in the main combustion zone, and the lateral jet formed by the mixing hole has a better effect on the adjustment of the combustion chamber outlet temperature distribution in the mixing zone.

Description

Technical Field

[0001] The present invention relates to the technical field of main combustion hole structures, and more particularly to a main combustion hole air intake bucket-shaped structure applied to a high-temperature rise main combustion chamber. Background Art

[0002] The continuous improvement of aircraft engine performance is driving the design of main combustion chambers toward higher thrust-to-weight ratios, higher temperature rises, higher fuel-to-air ratios, and lower pollution. A direct consequence of this high fuel-to-air ratio is the corresponding increase in the equivalence ratio of the main combustion zone. To suppress visible smoke, the average equivalence ratio of the main combustion zone must be controlled within 1.4. Therefore, the gas volume in the main combustion zone must be increased to control the equivalence ratio. This increase in the gas volume in the main combustion zone results in a larger head height during design, which in turn increases the combustion flow space within the flame tube to accommodate the increased head intake and combustion gas volume. Furthermore, as the head height increases, the reignition height also increases. Since ignition and flameout are similar phenomena and share the same physical nature, a higher head height also improves combustion stability, a development trend in high-performance aircraft engines.

[0003] In the main combustion zone, the cross-flow jets from the main burner holes serve to jointly create and interrupt the recirculation zone, thereby intensifying the combustion process. In the mixing zone, the cross-flow jets from the mixing holes serve to adjust the combustion chamber's outlet temperature distribution. The main burner hole jets work in conjunction with the swirler swirl to shape the flow pattern in the main combustion zone. The penetration depth of the opposed main burner hole jets is generally half the height of the flame tube head, significantly shortening the recirculation zone and improving combustion intensity in the main combustion zone. Furthermore, the low-pressure zone created by the swirler causes a portion of the jet (usually half of the main burner hole jet enters the recirculation zone) to recirculate, enhancing the combustion function in the recirculation zone.

[0004] The direct problem caused by the increase in the head height of the flame tube in the high-temperature main combustion chamber is that the ability of the simple flat hole structure of the original main combustion hole and mixing hole to play its role is greatly reduced, which will lead to many problems, such as poor oil and gas mixing and uniformity, reduced combustion efficiency and outlet temperature distribution quality, etc.

[0005] Therefore, we proposed a main combustion hole air intake bucket structure applied to the high temperature rise main combustion chamber to solve the above problems. Summary of the Invention

[0006] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a main combustion hole air intake bucket structure applied to a high temperature rise main combustion chamber to solve the problems raised in the above-mentioned background technology.

[0007] To achieve the above-mentioned object, the present invention provides the following technical solutions: a main combustion hole air intake bucket-shaped structure applied to a high-temperature rise main combustion chamber, comprising a flame tube;

[0008] A main combustion hole extends from the flame tube, and the lower end portion of the rear edge of the main combustion hole is tilted inward to form a spoon end arc surface, and an elliptical arc opening is provided from the front edge of the main combustion hole to the spoon end arc surface of the main combustion hole;

[0009] The central axis of the main combustion hole is perpendicular to the central axis of the flame tube.

[0010] Compared with the traditional simple circular flat hole structure, when the main combustion hole and mixing hole of the high-temperature rise main combustion chamber adopt the air intake bucket type structure, the transverse jet formed by the main combustion hole has a stronger effect on the truncation and combination of the recirculation zone in the main combustion zone, and the transverse jet formed by the mixing hole has a better effect on adjusting the temperature distribution of the combustion chamber outlet in the mixing zone.

[0011] In a preferred embodiment, there are four main combustion holes, two on each of the upper and lower walls of the flame tube, and they are arranged crosswise, that is, the transverse jets of the main combustion holes are staggered with each other.

[0012] In a preferred embodiment, the main combustion hole intake ratio is 16.9%, then according to the flow formula ;

[0013] The flow coefficient is set to 0.75, which makes the total pressure loss of the flame tube 3.5%;

[0014] but .

[0015] In a preferred embodiment, the radius of the main combustion hole is 6.5 mm, and the vertical depth of the main combustion hole structure inserted into the flame tube is 10 mm.

[0016] In a preferred embodiment, the vertical depth from the folded position of the inner wall of the trailing edge of the main combustion hole to the bottom of the inner wall of the spoon end arc surface is 1 / 4 of the vertical depth of the main combustion hole structure inserted into the flame tube.

[0017] In a preferred embodiment, the horizontal width of the bottom of the inner wall of the spoon end arc surface from the inner wall of the trailing edge of the main combustion hole is 1 / 2 of the vertical depth from the folding position of the inner wall of the trailing edge of the main combustion hole to the bottom of the inner wall of the spoon end arc surface.

[0018] In a preferred embodiment, there are four main combustion holes and four mixing holes, two on each of the upper and lower walls of the flame tube and they are arranged crosswise, and the main combustion holes and the mixing holes on the same wall are arranged crosswise, that is, a double cross arrangement is adopted.

[0019] Technical effects and advantages of the present invention:

[0020] 1. The main combustion hole adopts an air inlet bucket-shaped structure, and its lateral jet has greatly enhanced the cutoff and combined formation effect on the recirculation zone, which strengthens the oil and gas mixing and uniformity in the main combustion zone and strengthens the combustion process in the main combustion zone; secondly, the structural design is "short in front and long in the back", which increases the proportion of gas volume of the main combustion hole jet entering the recirculation zone, facilitates the formation of the recirculation zone with the swirl gas volume, and conforms to the concept of head-on flow, so as to avoid hindering the development of the recirculation zone in the main combustion zone as much as possible; in addition, since the direction of the inner and outer annular cavities introduced by the main combustion hole is opposite to the inclination direction of the "spoon" end of the structure, this design can make the inner and outer annular cavity airflow contact with the long wall surface on the right side of the main combustion hole with a larger area after being introduced into the main combustion hole, and the residence time is increased, which is convenient for cooling the wall surface, avoiding ablation, and plays an auxiliary role in enhancing the penetration depth. The control of the lateral jet direction can also be enhanced by adjusting the inclination angle of the "spoon" end.

[0021] 2. The mixing hole adopts an air intake bucket-shaped structure, which makes the penetration depth of the lateral jet greater, the unburned hydrocarbon (UHC) emission at the combustion chamber outlet lower, the combustion efficiency higher, and the outlet temperature distribution quality higher.

[0022] 3. The mixing hole adopts an air scoop-shaped structure, which can bring more unburned hydrocarbons entrained by the flame tube film cooling jet into the incoming hot gas for chemical reaction. Compared with simple circular flat hole structures, the cross-jet direction of the mixing hole is more inclined towards the mainstream, resulting in longer residence time, better afterburning effect, and better adjustment of the combustion chamber outlet temperature distribution. In addition, the inclination angle of the mixing hole "scoop" end can be adjusted according to the combustion field results to better adjust the combustion chamber outlet temperature distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the central cross section of the air intake bucket-shaped main combustion hole structure in the present invention;

[0024] Figure 2 This is a sketch of the air intake bucket-shaped main combustion hole structure in the present invention;

[0025] Figure 3 This is the central cross-section of the high-temperature rise three-swirl main combustion chamber of Scheme 001 of the present invention;

[0026] Figure 4 The main combustion holes and the mixing holes are arranged in a double cross manner in the present invention;

[0027] Figure 5 This is the velocity streamline diagram of the central section of Scheme 001 under the design working condition of the present invention;

[0028] Figure 6 This is the velocity streamline diagram of the central section of Scheme 002 under the design working condition of the present invention;

[0029] Figure 7This is the velocity streamline diagram of the central section of Scheme 003 under the design working condition of the present invention;

[0030] Figure 8 This is the velocity streamline diagram of the central section of Scheme 004 under the design working condition of the present invention;

[0031] Figure 9 This is the temperature distribution cloud diagram of the central section of Scheme 001 under the design working conditions of the present invention;

[0032] Figure 10 This is the temperature distribution cloud diagram of the central section of Scheme 002 under the design working conditions of the present invention;

[0033] Figure 11 This is the temperature distribution cloud diagram of the central section of Scheme 003 under the design working conditions of the present invention;

[0034] Figure 12 This is the temperature distribution cloud diagram of the central section of Scheme 004 under the design working conditions of the present invention;

[0035] Figure 13 This is the temperature distribution cloud diagram of the outlet section of Scheme 001 under the design working conditions of the present invention;

[0036] Figure 14 This is the temperature distribution cloud diagram of the outlet section of Scheme 002 under the design working conditions of the present invention;

[0037] Figure 15 This is the temperature distribution cloud diagram of the outlet section of Scheme 003 under the design working conditions of the present invention;

[0038] Figure 16 This is the temperature distribution cloud diagram of the outlet section of Scheme 004 under the design working conditions of the present invention;

[0039] Figure 17 This is the velocity streamline diagram of the central section of Scheme 001 under the slow train condition in the present invention;

[0040] Figure 18 This is the velocity streamline diagram of the central section of Scheme 002 under the slow train condition in the present invention;

[0041] Figure 19 This is the velocity streamline diagram of the central section of Scheme 003 under the slow train condition in the present invention;

[0042] Figure 20 This is the velocity streamline diagram of the central section of Scheme 004 under the slow train condition in the present invention;

[0043] Figure 21 This is the temperature distribution cloud diagram of the central section of Scheme 001 under the slow running condition in the present invention;

[0044] Figure 22 This is the temperature distribution cloud diagram of the central section of Scheme 002 under the slow running condition in the present invention;

[0045] Figure 23 This is the temperature distribution cloud diagram of the central section of Scheme 003 under the slow running condition in the present invention;

[0046] Figure 24 This is the temperature distribution cloud diagram of the central section of Scheme 004 under the slow running condition in the present invention;

[0047] Figure 25 This is the temperature distribution cloud diagram of the outlet section of Scheme 001 under the slow running condition in the present invention;

[0048] Figure 26 This is the temperature distribution cloud diagram of the outlet section of Scheme 002 under slow running conditions in the present invention;

[0049] Figure 27 This is the temperature distribution cloud diagram of the outlet section of Scheme 003 under the slow running condition in the present invention;

[0050] Figure 28 This is the temperature distribution cloud diagram of the outlet section of Scheme 004 under slow running condition in the present invention;

[0051] Figure 29 is the average radial temperature distribution curve of different schemes under the design working conditions of the present invention;

[0052] Figure 30 This is the average radial temperature distribution curve of different schemes under slow running condition in the present invention. DETAILED DESCRIPTION

[0053] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0054] Reference Figure 1-30 , the main combustion hole air inlet bucket type structure applied to the high temperature rise main combustion chamber. Taking the designed high temperature rise three-swirl main combustion chamber as an example, an annular combustion chamber is selected with 20 heads, retaining the main combustion hole and mixing hole. The research working conditions, structural limit size, overall gas volume distribution and structural parameters of the swirlers at all levels of the single-head annular combustion chamber are shown in Tables 1, 2, 3 and 4.

[0055] Table 1 Research conditions of high temperature rise three-swirl main combustion chamber

[0056] ;

[0057] Table 2 Structural limitations of the high-temperature rise three-swirl main combustion chamber

[0058] ;

[0059] Table 3 Overall gas volume distribution of high temperature rise three-swirl main combustion chamber

[0060] ;

[0061] Table 4 Structural parameters of cyclones at each level

[0062] ;

[0063] The main combustion hole air intake bucket structure is specifically designed as follows: Figure 1 and instructions attached Figure 2 The flame tube is included; the M and N lines represent the inner wall of the flame tube, and the L and P lines represent the outer wall of the flame tube. The L line is parallel to the M line and is the straight segment of the flame tube wall. The flame tube wall thickness h is generally taken as 2mm in the design. The hole front edge depth, that is, the K line height, is generally taken in the range of a=0.3-0.5mm based on design experience. The a value of the designed high-temperature rise three-swirl main combustion chamber is 0.4mm. The H line is the central axis of the main combustion hole, and the H line is perpendicular to the central axis of the flame tube (that is, the line connecting the midpoint of the combustion chamber inlet and the midpoint of the flame tube outlet).

[0064] The inner surface of the leading edge of the main combustion hole, i.e., line Q, is parallel to line H, and the length d of line G is the radius of the main combustion hole.

[0065] According to Table 3, the air intake ratio of the main combustion hole is 16.9%;

[0066] According to the flow formula ;

[0067] The flow coefficient is set to 0.75, making the total pressure loss coefficient of the flame tube 3.5%;

[0068] but There are four main combustion holes in total, two on the upper and lower walls of the flame tube, and they are arranged crosswise. That is, the lateral jets of the main combustion holes are staggered, which is conducive to promoting the mutual impact and shearing of the jets of the inner and outer ring main combustion holes, forming a relatively full recirculation area. The iterative calculation results show that the radius of the main combustion hole is d = 6.5mm.

[0069] A main combustion hole extends from the flame tube, wherein line A and line B are the inner and outer wall surfaces of the vertical portion of the rear edge of the main combustion hole, and the lower end portion of the rear edge of the main combustion hole is tilted inward to form a spoon end arc surface, and an elliptical arc-shaped opening is provided extending from the front edge of the main combustion hole to the spoon end arc surface of the main combustion hole, wherein line D and line F are the inner and outer wall surfaces of the spoon end arc surface, wherein line G is the horizontal width of the inner wall surface of the vertical portion of the rear edge of the main combustion hole from line H, the central axis of the main combustion hole, and line E is the horizontal width of the lower end surface of the spoon end arc surface.

[0070] Figure 2 Lines A and B are parallel to line H, line D is parallel to line F, and line C is located in the middle of the flame tube wall. Line C is parallel to line G, and both lines C and G are perpendicular to line H. The depth of the air intake bucket-shaped main combustion hole structure inserted into the flame tube, i.e., the length b of line H, is generally within the range of 10-11mm based on design experience. Excessive lengths can easily cause ablation. The b value for the designed high-temperature rise three-swirl main combustion chamber is 10mm.

[0071] Figure 1 The middle line E is perpendicular to the D line and intersects at point 3, and is perpendicular to the F line and intersects at point 4. Point 1 is the intersection of the D line and the T line, and point 2 is the intersection of the F line and the S line. The line connecting point 1 and point 2 is parallel to the G line, and point 3 is on the G line.

[0072] In a preferred embodiment, the horizontal width of the bottom of the inner wall of the spoon end arc surface from the inner wall of the trailing edge of the main combustion hole is 1 / 2 of the vertical depth from the folding position of the inner wall of the trailing edge of the main combustion hole to the bottom of the inner wall of the spoon end arc surface.

[0073] The main burner hole wall thickness c, or the length of lines C and E, is generally taken as 1mm based on design experience. The height y of point 1 from line G is generally taken as 1 / 4 of the length b of line H, based on design experience. This means the vertical depth from the folded position of the main burner hole's trailing edge inner wall to the bottom of the scoop-end curved inner wall is 1 / 4 of the vertical depth of the main burner hole structure inserted into the flame tube. The width x of point 3 from line A is generally taken as 1 / 2 of y, based on design experience. This means the horizontal width from the bottom of the scoop-end curved inner wall to the main burner hole's trailing edge inner wall is 1 / 2 of the vertical depth from the folded position of the main burner hole's trailing edge inner wall to the bottom of the scoop-end curved inner wall. Although the design of the intake bucket structure is primarily based on the main burner hole, multiple simulations have verified that this structure is effectively applicable to mixing holes.

[0074] The designed single-head high-temperature rise triple-swirl main combustion chamber has four main combustion holes and four mixing holes, two on each of the upper and lower walls of the flame tube, and two cross-arranged. The main combustion holes and mixing holes are arranged cross-wise on the same wall, that is, a double cross-arrangement is adopted. To verify the performance improvement of the main combustion holes and mixing holes using an air intake bucket structure, while ensuring the consistency of the hole diameter, axial position and circumferential radial arrangement;

[0075] Four schemes were designed for comparative study, as shown in Table 5.

[0076] Table 5 Research plan for selecting the structure of main combustion holes and mixing holes

[0077] ;

[0078] Taking the research scheme 001 as an example, the designed high temperature rise three swirl main combustion chamber structure model is shown in the attached manual. Figure 3 and instructions attached Figure 4The simulation results of the high-temperature rise three-swirl main combustion chamber of different schemes under design conditions and slow running conditions are shown in Table 6 and Table 7 respectively.

[0079] Table 6 Simulation results of high temperature rise three-swirl main combustion chamber under different design conditions

[0080] ;

[0081] Table 7 Simulation results of high temperature rise three-swirl main combustion chamber under slow running conditions of different schemes

[0082] ;

[0083] The outlet temperature distribution factor (OTDF) refers to the ratio of the maximum temperature Tmax at the combustion chamber outlet exceeding the average temperature Tave to the combustion chamber temperature rise. It is called the hot spot index and is defined as follows:

[0084] ;

[0085] The Radial Temperature Distribution Factor (RTDF) refers to the ratio of the difference between the circumferentially averaged radial temperature distribution at the combustion chamber outlet and the average outlet gas temperature to the average inlet and outlet gas temperatures. It is used for general assessment of the impact on turbine life.

[0086] The definition formula is as follows:

[0087] ;

[0088] For aviation kerosene combustion, the following approximate expression can be derived:

[0089] Combustion efficiency:

[0090] ;

[0091] Where UHC is the unburned hydrocarbons in the combustion products except CH4, and the values ​​of each component are volume percentages.

[0092] The combustion chamber total pressure loss coefficient refers to the ratio of the combustion chamber total pressure loss to the inlet total pressure, and the combustion chamber total pressure loss is the difference between the inlet total pressure and the outlet total pressure. The definition formula is as follows:

[0093] ;

[0094] The formula for calculating pollutant emissions is as follows:

[0095] ;

[0096] ;

[0097] ;

[0098] ;

[0099] Wherein, molef-NOx is the mole fraction of nitrogen oxides, molef-soot is the mole fraction of smoke, molef-UHC is the mole fraction of unburned hydrocarbons, and molef-CO is the mole fraction of carbon monoxide.

[0100] Under the design and slow running conditions, the center section velocity streamlines, temperature distributions, outlet section temperature distributions, and RTDF curves of the high temperature rise three-swirl main combustion chamber of different schemes are shown in the attached manual. Figure 5 -Instruction manual included Figure 30 shown.

[0101] Through comparative analysis, it can be found that compared with the traditional simple circular flat hole structure, when the main combustion hole and mixing hole of the high-temperature rise main combustion chamber adopt the air intake bucket type structure, the transverse jet formed by the main combustion hole has a stronger effect on the truncation and joint formation of the recirculation zone in the main combustion zone, and the transverse jet formed by the mixing hole has a better effect on adjusting the temperature distribution of the combustion chamber outlet in the mixing zone.

[0102] This is because as the head height increases, the cross-sectional area of ​​the entire flame tube increases accordingly. From the comparison between Scheme 001 and Scheme 002, and Scheme 003 and Scheme 004, it can be seen that the penetration depth of the lateral jet formed by the main combustion hole of the simple flat hole structure is only to the height of the main combustion stage swirl, and the truncation and joint formation effect on the recirculation zone is greatly weakened, which will cause the axial length of the recirculation zone to be greatly lengthened, and the oil and gas mixing and uniformity in the main combustion zone to deteriorate, and then the combustion in the main combustion zone will be relatively weakened and extend more to the back of the main combustion hole, ultimately affecting the combustion efficiency and the quality of the outlet temperature distribution. If the main combustion hole adopts the air intake bucket type structure, first of all, it extends a certain distance into the flame tube, which enhances the penetration depth, and the penetration depth can reach the center axis of the flame tube. In the designed high-temperature three-swirl main combustion chamber, all the swirl gas volume in the pre-combustion stage and 80% of the swirl gas volume outside the pre-combustion stage are used to produce the traditional swirl cup recirculation zone. Therefore, it can be seen that the main combustion hole adopts the air intake bucket type structure, and its transverse jet has greatly enhanced the truncation and combined formation effect on the recirculation zone, which enhances the oil and gas mixing and uniformity in the main combustion zone and strengthens the combustion process in the main combustion zone; secondly, the structural design is "short in front and long in the back", which enhances the main combustion hole jet entering The proportion of gas volume entering the recirculation zone is convenient for combining with the swirl gas volume to form the recirculation zone, and is in line with the upstream flow concept, so as to avoid hindering the development of the recirculation zone in the main combustion zone as much as possible; in addition, since the direction of the inner and outer annular cavities introduced by the main combustion hole is opposite to the inclination direction of the "spoon" end of the structure, this design can make the inner and outer annular cavity airflows have a larger area of ​​contact with the long wall surface on the right side of the main combustion hole after being introduced into the main combustion hole, and the residence time is increased, which is convenient for cooling the wall surface and avoiding ablation, and plays an auxiliary role in enhancing the penetration depth. The control of the lateral jet direction can also be enhanced by adjusting the inclination angle of the "spoon" end.

[0103] Comparisons between Schemes 001 and 003, and between Schemes 002 and 004, show that the inlet scoop-shaped structure of the mixing hole allows for greater penetration of the lateral jet, resulting in lower unburned hydrocarbon (UHC) emissions at the combustion chamber outlet, higher combustion efficiency, and a higher quality outlet temperature distribution. The formation mechanism of UHC is primarily governed by physical factors. Unburned particles, fuel vapor, and partially reacted fuel vapor at the combustion chamber outlet primarily result from the quenching effect of the air film on these products. In the designed high-temperature main combustion chamber, the main stage fuel spray angle is 90°. During combustion, the tip of the flame is entrained and captured in the film cooling jet of the flame tube. The relatively low temperature of the film cooling jet halts the reaction of these unreacted particles, fuel vapor, and partially reacted fuel vapor, resulting in the generation of a large amount of UHC. The mixing holes, with their inlet scoop-shaped structure, can bring more unburned hydrocarbons entrained by the flame tube's film-cooling jet into the incoming hot gas stream for chemical reactions. Furthermore, compared to simpler circular flat holes, the lateral jet direction of the mixing holes is more inclined toward the mainstream, resulting in a longer residence time, better afterburning, and a more effective adjustment of the combustion chamber outlet temperature distribution. Furthermore, the combustion chamber outlet temperature distribution can be further adjusted by adjusting the inclination angle of the mixing hole's "scoop" end, based on the combustion field results.

[0104] The best results are achieved when both the main combustion and mixing holes in the high-temperature rise triple-swirl main combustor adopt an intake bucket-shaped structure. A comparison between Schemes 001 and 004 shows that, under both design and slow-run conditions, Scheme 004 achieves higher average outlet temperatures and lower maximum outlet temperatures, resulting in a lower outlet temperature distribution coefficient (OTDF). The average radial temperature distribution coefficient (RTDF) is also lower, and the RTDF curve is fuller and more balanced. Therefore, a comprehensive analysis indicates that Scheme 004 offers higher quality outlet temperature distribution under design and slow-run conditions. Furthermore, Scheme 004 exhibits higher combustion efficiency under design conditions, with lower NOx, soot, and unburned hydrocarbon (UHC) emissions than Scheme 001.

[0105] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. The main combustion hole air intake bucket structure used in the high temperature rise main combustion chamber is characterized by: Including flame tube; A main combustion hole extends from the flame tube, and the lower end portion of the rear edge of the main combustion hole is tilted inward to form a spoon end arc surface, and an elliptical arc opening is provided from the front edge of the main combustion hole to the spoon end arc surface of the main combustion hole; The length of the leading edge of the main combustion hole is shorter than the trailing edge of the main combustion hole, forming a "short in front and long in the back" design; The vertical depth from the folded position of the inner wall of the trailing edge of the main combustion hole to the bottom of the inner wall of the arc surface of the spoon end is 1 / 4 of the vertical depth of the main combustion hole structure inserted into the flame tube; The horizontal width of the bottom of the inner wall of the spoon end arc surface from the inner wall of the rear edge of the main combustion hole is 1 / 2 of the vertical depth from the folding position of the inner wall of the rear edge of the main combustion hole to the bottom of the inner wall of the spoon end arc surface; The central axis of the main combustion hole is perpendicular to the central axis of the flame tube.

2. The main combustion hole air intake bucket structure used in a high temperature rise main combustion chamber according to claim 1, characterized in that: There are four main combustion holes designed, two on the upper and lower walls of the flame tube, and they are arranged crosswise, that is, the lateral jets of the main combustion holes are staggered with each other.

3. The main combustion hole air intake bucket structure used in a high temperature rise main combustion chamber according to claim 1, characterized in that: The radius of the main combustion hole is 6.5mm, and the vertical depth of the main combustion hole structure inserted into the flame tube is 10mm.

4. The main combustion hole air intake bucket structure used in a high temperature rise main combustion chamber according to claim 1, characterized in that: There are four main combustion holes and four mixing holes, two on each of the upper and lower walls of the flame tube and they are arranged crosswise. The main combustion holes and mixing holes on the same wall are arranged crosswise, that is, a double cross arrangement is adopted.

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