Improved aero-engine three-rotational-flow combustion chamber with large hole and small hole coupled

Abstract

The invention discloses an improved aero-engine three-cyclone combustion chamber with coupled large and small holes, which comprises inner ring main combustion holes, outer ring main combustion holes, inner ring mixing holes and outer ring mixing holes, and is characterized in that inner ring auxiliary small holes with the same number as the inner ring mixing holes are formed in the inner ring mixing holes in the axial direction; outer ring auxiliary small holes with the same number as the outer ring mixing holes are formed in the outer ring mixing holes in the axial direction, the sum of the area of the inner ring mixing holes and the area of the inner ring auxiliary small holes is matched with the area of the inner ring main combustion holes, and the sum of the area of the outer ring mixing holes and the area of the outer ring auxiliary small holes is matched with the area of the outer ring main combustion holes. The method is suitable for an aero-engine combustion chamber, can obviously improve the uniformity of an outlet temperature field of the engine combustion chamber, and improves the working reliability of an engine.

Description

Technical Field

[0001] The present invention relates to the technical field of aero-engines, and specifically to an improved three-swirling combustor of an aero-engine with coupling of large and small holes. Background Technique

[0002] An aero-engine is a device that converts the thermal energy or other forms of energy of aviation fuel into mechanical energy to provide power for aircraft, helicopters and other aircraft, and is a highly complex and precise thermal machine. As the heart of an aircraft, the aero-engine is known as the "flower of industry", which directly affects the performance, reliability and economy of the aircraft, and is an important manifestation of a country's scientific and technological, industrial and national defense strength. Only a few countries in the world, such as the United States, Russia, China, the United Kingdom, and France, can independently develop high-performance aero-engines, and the technical threshold is very high.

[0003] The combustor is one of the core components of the engine. With the development of high-performance aero-engines, the temperature rise in the combustor has increased significantly, and the three-swirling combustor configuration has gradually become one of the mainstream configurations in the current combustor design. The high temperature rise necessarily requires a further increase in the equivalence ratio of the combustor, that is, a further significant increase in the combustion temperature. Under limited space, the mixing difficulty between high-temperature and low-temperature air increases significantly. In some cases, when reaching the combustor outlet, the mixing of high-temperature gas and low-temperature air is not ideal enough, and the outlet temperature field will show a certain degree of uneven distribution. The unevenness of the combustor outlet temperature field will significantly affect the downstream turbine cooling and thus affect its safe operation. Therefore, improving the mixing characteristics plays an important role in developing high-performance combustors.

[0004] In the design of the three-swirling combustor, much research has been done on the distribution characteristics of the main combustion and mixing structures, and relatively reasonable configuration, distribution position and other information have been macroscopically determined. However, more detailed research has found that in the case of a high fuel-air ratio, in order to make the cold mixing air penetrate to the center position of the combustor, it is necessary to make the outlet kinetic energy of the cold mixing air from the mixing holes larger. A side effect of this is that the mixing of high-temperature gas and low-temperature mixing air is insufficient near the position of the flame tube close to the outlet of the mixing holes, resulting in more high-temperature gas near the wall. The propagation of this part of the high-temperature gas downstream will cause a high-temperature area to appear near the flame tube wall at the combustor outlet, resulting in uneven distribution of the outlet temperature field and increasing the risk of ablation of the downstream turbine. Therefore, an optimized design method for this problem is needed. Summary of the Invention

[0005] Aiming at the above problems and considering the deficiencies of the prior art, the purpose of the present invention is to provide an improved three-swirling combustor of an aero-engine with coupling of large and small holes to improve the distribution uniformity of the combustor outlet temperature field and improve the working reliability of the engine.

[0006] To achieve the above object, the present invention provides the following technical solutions for implementation:

[0007] An improved three - swirl combustor for an aero - engine with coupled large and small holes, comprising an inner - ring main combustion hole, an outer - ring main combustion hole, inner - ring mixing holes and outer - ring mixing holes, characterized in that: along the axial direction of the inner - ring mixing holes, inner - ring auxiliary small holes with the same number as the inner - ring mixing holes are provided; along the axial direction of the outer - ring mixing holes, outer - ring auxiliary small holes with the same number as the outer - ring mixing holes are provided; and the sum of the areas of the inner - ring mixing holes and the inner - ring auxiliary small holes is adapted to the inner - ring main combustion hole, and the sum of the areas of the outer - ring mixing holes and the outer - ring auxiliary small holes is adapted to the outer - ring main combustion hole.

[0008] Based on the original combustor mixing configuration, the present invention adds auxiliary small holes in front of or behind the axes of the inner - and outer - ring mixing holes to improve the mixing configuration. Slightly reduce the diameters of the inner - and outer - ring mixing holes, and at the same time, at a relatively short distance in the front or rear of the axial combustor of the inner - and outer - ring mixing holes, add the same number of auxiliary small holes as the number of mixing holes along the axial direction. Keep the sum of the areas of the auxiliary small holes and the corresponding mixing holes equal to the area of the original mixing holes after adding the auxiliary small holes, so as to basically maintain the same flow rate of the improved mixing holes and the original mixing holes, and only improve the single - strand mixing jet into a two - strand jet of the upstream small jet and the main mixing - hole jet.

[0009] Preferably, the positions and sizes of the inner - ring auxiliary small holes and the outer - ring auxiliary small holes are adapted to the working state and working parameters, and the sum of the areas of the inner - ring auxiliary small holes and the inner - ring mixing holes remains unchanged, and the sum of the areas of the outer - ring auxiliary small holes and the outer - ring mixing holes remains unchanged.

[0010] The diameter of the inner - ring auxiliary small hole is 1 / 5 of the diameter of the inner - ring mixing hole, and the diameter of the outer - ring auxiliary small hole is 1 / 5 of the diameter of the outer - ring mixing hole.

[0011] Preferably, the small holes added before the mixing holes are correspondingly distributed directly in front of the mixing holes and act together with the mixing holes to optimize the structure of the mixing holes. The flow rate of the improved mixing holes and the front - part small holes is basically equal to the flow rate of the original mixing holes, but the air flowing into the combustor through the two mixing large and small holes is redistributed, so that the low - temperature air flowing through the small holes improves the high - temperature region near the flame - tube wall surface, and the low - temperature air flowing through the large holes improves the high - temperature region in the center of the combustor, thereby overall improving the mixing effect of the high - temperature gas and the low - temperature air, optimizing the temperature distribution at the combustor outlet, and improving the distribution quality of the outlet temperature field.

[0012] Preferably, the small holes added after the mixing holes are correspondingly distributed directly downstream of the mixing holes and cooperate with the mixing holes to optimize the structure of the mixing holes. The flow rate of the improved mixing holes and the subsequent small holes is basically equal to the flow rate of the original mixing holes, but the air flowing into the combustion chamber through the two mixing holes of different sizes is redistributed, so that the low-temperature air flowing through the small holes improves the high-temperature area near the flame tube wall surface, and the low-temperature air flowing through the large holes improves the high-temperature area in the center of the combustion chamber, thereby overall improving the mixing effect of the high-temperature gas and the low-temperature air, optimizing the temperature distribution at the outlet of the combustion chamber, and improving the distribution quality of the outlet temperature field.

[0013] Preferably, the positions and sizes of the inner ring auxiliary small holes and the outer ring auxiliary small holes are adapted to the working state and working parameters. The distance and size of the small holes added in front of or behind the mixing holes can be adjusted according to different flight conditions, working parameters, etc. to meet the requirements of the engine combustion chamber under different working conditions.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. Improve the uniformity of the temperature field at the outlet of the combustion chamber

[0016] The improved mixing hole structure and method effectively improve the problem of uneven temperature field distribution at the outlet of the traditional combustion chamber, significantly reduce the risk of the occurrence of local high-temperature areas, and protect the combustion chamber wall surface and downstream turbine components.

[0017] 2. Improve the combustion efficiency

[0018] By optimizing the design of the mixing holes, more sufficient mixing of the high-temperature gas, fuel and air is achieved, the phenomenon of incomplete fuel combustion is reduced, and the combustion efficiency is significantly improved.

[0019] 3. Reduce pollutant emissions

[0020] Due to more uniform mixing, improved combustion efficiency, and weakened local high-temperature areas, the generation amounts of harmful combustion chamber pollutants such as NOx and CO are significantly reduced, which is beneficial to environmental protection.

[0021] 4. Extend the service life of the combustion chamber

[0022] Since the temperature field is more uniform, the thermal load borne by the combustion chamber wall surface is reduced, and the thermal stress and thermal shock are reduced, thereby extending the service life of the combustion chamber.

[0023] 5. Enhance the engine performance

[0024] A more uniform temperature field and higher combustion efficiency contribute to improving the overall performance of the engine, including thrust, safety and fuel economy.

[0025] 6. Improve the working safety

[0026] Since the risk of local high-temperature zones and incomplete combustion is reduced, the risk of combustion chamber failure is decreased, and the working safety is improved.

[0027] 7. Strong adaptability

[0028] This structure is compactly designed and the method is flexible. It can be adapted and optimized according to different models of aeroengines, and has a relatively wide applicability. Description of the drawings

[0029] Figure 1 Schematic diagram of the mixing hole structure before this improvement;

[0030] Figure 2 Schematic diagram of the improved structure with small holes added to the front side of the mixing hole of the present invention;

[0031] Figure 3 Schematic diagram of the improved structure with small holes added to the rear side of the mixing hole of the present invention. Specific implementation manners

[0032] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0033] Please refer to Figures 1-3 , Figure 1 Schematic diagram of the structure before this improvement; there are only the inner ring main combustion holes 1, the outer ring main combustion holes 2, the inner ring mixing holes 3, and the outer ring mixing holes 4.

[0034] Example 1:

[0035] Figure 2 Schematic diagram of the improved structure with small holes added to the front side of the mixing hole of the present invention; on the front side along the axis of the inner ring mixing hole 3, there are inner ring auxiliary small holes 5 with the same number as the inner ring mixing hole 3, and on the front side along the axis of the outer ring mixing hole 4, there are outer ring auxiliary small holes 6 with the same number as the outer ring mixing hole 4. Moreover, the sum of the areas of the inner ring mixing hole 3 and the inner ring auxiliary small holes 5 is adapted to the inner ring main combustion hole 1, and the sum of the areas of the outer ring mixing hole 4 and the outer ring auxiliary small holes 6 is adapted to the outer ring main combustion hole 2.

[0036] This embodiment makes improvements to the mixing configuration and method. Slightly reduce the diameters of the inner and outer ring mixing holes. At the same time, at a relatively short distance along the axial direction towards the front of the combustion chamber, add the same number of auxiliary small holes as the number of mixing holes. Keep the sum of the areas of the auxiliary small holes and the corresponding mixing holes equal to the original mixing hole area after adding the auxiliary small holes, so as to basically maintain the same flow rate of the improved mixing holes and the original mixing holes, and only improve the single-strand mixing jet into two jets, namely the small jet upstream and the jet from the main mixing hole.

[0037] The positions and sizes of the inner ring auxiliary small holes 5 and the outer ring auxiliary small holes 6 are adapted to the working conditions and working parameters. And the sum of the areas of the inner ring auxiliary small holes 5 and the inner ring mixing holes 3 remains unchanged. The diameter of the inner ring auxiliary small holes is 1 / 5 of the diameter of the inner ring mixing holes. The sum of the areas of the outer ring auxiliary small holes 6 and the outer ring mixing holes 4 remains unchanged. The diameter of the outer ring auxiliary small holes is 1 / 5 of the diameter of the outer ring mixing holes.

[0038] Embodiment 2:

[0039] Figure 3 This is a schematic diagram of the improved structure with small holes added behind the mixing holes of the present invention. Add auxiliary small holes at a relatively short distance axially behind the inner and outer ring mixing holes to optimize the mixing hole configuration and method. Slightly reduce the diameters of the inner and outer ring mixing holes. At the same time, at a relatively short distance along the axial direction towards the downstream of the combustion chamber, add the same number of auxiliary small holes as the number of mixing holes. Keep the sum of the areas of the auxiliary small holes and the corresponding mixing holes equal to the area of the mixing holes before the addition, so as to basically maintain the same flow rate of the improved mixing holes and the original mixing holes, and only improve the single-strand mixing jet into two jets, namely the small jet downstream and the jet from the main mixing hole.

[0040] The positions and sizes of the small holes added in the front and rear of the mixing holes can be adjusted according to different flight conditions and working states to meet the combustion requirements of the combustion chamber under different working conditions.

[0041] The positions and sizes of the inner ring auxiliary small holes 5 and the outer ring auxiliary small holes 6 are adapted to the working conditions and working parameters. And the sum of the areas of the inner ring auxiliary small holes 5 and the inner ring mixing holes 3 remains unchanged. The sum of the areas of the outer ring auxiliary small holes 6 and the outer ring mixing holes 4 remains unchanged.

[0042] The present invention aims to improve the mixing effect of high-temperature gas and low-temperature air, thereby enhancing the uniformity of the distribution of the outlet temperature field and reducing pollutant emissions. The present invention slightly reduces the diameters of the inner and outer ring mixing holes, and sets a number of additional small holes at a relatively short distance before or after the mixing holes. After improvement, ensure that the sum of the areas of the mixing holes and the corresponding small holes is equal to the area of the mixing holes before improvement. On the premise of basically maintaining the flow rate of the mixing holes, regulate the flow field through the injection of the small holes to achieve the effect of optimized mixing.

[0043] In summary, an improved three - swirl combustor for an aero - engine with coupled large and small holes of the present invention has significant advantages in aspects such as improving the uniformity of the combustor outlet temperature distribution, enhancing combustion performance, reducing pollutant emissions, and extending service life, and has a beneficial promoting effect on the development of aero - engine technology.

[0044] The above - mentioned specific description further details the purpose, technical solution, and beneficial effects of the invention. It should be understood that the above - mentioned is only a specific embodiment of the present invention and is not used to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. An improved three - swirl combustor for an aero - engine with coupled large and small holes, comprising an inner - ring main combustion hole (1), an outer - ring main combustion hole (2), an inner - ring mixing hole (3) and an outer - ring mixing hole (4), characterized in that: Axially arranged in the inner ring mixing holes (3) are inner ring auxiliary small holes (5) with the same number as the inner ring mixing holes (3), axially arranged in the outer ring mixing holes (4) are outer ring auxiliary small holes (6) with the same number as the outer ring mixing holes (4), and the sum of the areas of the inner ring mixing holes (3) and the inner ring auxiliary small holes (5) is adapted to the inner ring main combustion holes (1), and the sum of the areas of the outer ring mixing holes (4) and the outer ring auxiliary small holes (6) is adapted to the outer ring main combustion holes (2).

2. An improved three - swirl combustor for an aero - engine with coupling of large and small holes according to claim 1, characterized in that: Axially arranged on the front side of the inner ring mixing holes (3) are inner ring auxiliary small holes (5) with the same number as the inner ring mixing holes (3); axially arranged on the front side of the outer ring mixing holes (4) are outer ring auxiliary small holes (6) with the same number as the outer ring mixing holes (4).

3. An improved three - swirl combustor for an aero - engine with coupling of large and small holes according to claim 1, characterized in that: Axially arranged on the rear side of the inner ring mixing holes (3) are inner ring auxiliary small holes (5) with the same number as the inner ring mixing holes (3); axially arranged on the rear side of the outer ring mixing holes (4) are outer ring auxiliary small holes (6) with the same number as the outer ring mixing holes (4).

4. An improved three - swirl combustor for an aero - engine with coupling of large and small holes according to claim 1, characterized in that: The positions and sizes of the inner ring auxiliary small holes (5) and the outer ring auxiliary small holes (6) are adapted to the working state and working parameters, and the sum of the areas of the inner ring auxiliary small holes (5) and the inner ring mixing holes (3) remains unchanged, and the sum of the areas of the outer ring auxiliary small holes (6) and the outer ring mixing holes (4) remains unchanged.

5. An improved three - swirl combustor for an aero - engine with large - and - small - hole coupling according to claim 4, characterized in that: The diameter of the inner ring auxiliary small holes (5) is 1 / 5 of the diameter of the inner ring mixing holes (3), and the diameter of the outer ring auxiliary small holes (6) is 1 / 5 of the diameter of the outer ring mixing holes (4).

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