A high-efficiency cooled combustor liner

Abstract

The application discloses a high-efficiency-cooled flame tube of a swirl combustion chamber, and designs a cooling structure in different zones according to the flow characteristics of the swirl combustion chamber: discrete circular holes are adopted in the corner vortex zone; the discrete circular holes are densely arranged in the impingement zone to increase the heat exchange amount in the film hole and reduce the wall surface temperature of the high-heat-load impingement zone; shallow slot holes with a large film hole spacing are adopted in the development zone to reduce the cooling gas consumption and improve the film cooling efficiency. The high-efficiency-cooled structure is used to optimize the near-wall film cooling characteristics of the flame tube under the swirl inlet of the combustion chamber, the cooling gas utilization efficiency is high, the temperature distribution is uniform, and the high-efficiency-cooled structure is especially suitable for use under the condition that the cooling gas amount is small and the blowing is small.

Description

Technical Field

[0001] This invention relates to the field of high-efficiency composite cooling technology, and in particular to a swirling combustion chamber flame tube that can be efficiently cooled, mainly used for cooling the main combustion chamber flame tube of aero engines. Background Technology

[0002] The main combustion chamber is one of the three core components of an aero-engine. Air flows into the combustion chamber and mixes with aviation kerosene supplied by the nozzles, igniting and burning to produce high-temperature combustion gases that drive the turbine. The peak temperature of the combustion gases in modern aero-engine combustion chambers can exceed 2400 K, far higher than the melting point of the metal materials within the combustion chamber (around 1300 K). Therefore, the design of the combustion chamber requires careful consideration of the thermal protection scheme for the flame tube walls, while also ensuring structural integrity and durability.

[0003] Among various types of main combustion chambers, the swirl combustion chamber is the most widely used. The swirl combustion chamber uses a swirler to generate a low-speed recirculation zone to organize combustion. In the swirl combustion chamber, the rotating jet formed by the swirler interacts with the near-wall gas film of the flame tube, disrupting the formation and development of the gas film.

[0004] However, current swirl combustion chamber flame tube cooling structure designs do not consider the impact of the swirl on the near-wall gas film. This results in an inability to form an effective gas film distribution near the wall to isolate the high-temperature combustion gases, leading to localized hot spots in the flame tube and thus reducing its service life. Therefore, it is necessary to optimize the flame tube gas film cooling structure under swirl inlet conditions to improve cooling efficiency and extend the flame tube's service life. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a swirling combustion chamber flame tube that can be efficiently cooled, addressing the deficiencies mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A swirling combustion chamber flame tube capable of efficient cooling, wherein the tube wall of the swirling combustion chamber flame tube is a plate-shaped component that withstands a high-temperature heat source; The vortex region of the flame tube in the swirl combustion chamber has L rows of discrete circular holes equidistantly spaced along the axial direction, each hole forming an incident angle with the direction of the mainstream combustion gas. L is a natural number greater than or equal to 2, and the distance between adjacent rows of L discrete circular holes is D. L1 The distance between adjacent discrete circular holes in each row is D. L2 ; The swirl combustion chamber flame tube has M rows of discrete circular holes equidistantly spaced along the axial direction in the impact zone. These holes form an incident angle with the flow direction of the cooling medium. M is a natural number greater than or equal to 2, and the distance between adjacent rows of the M rows of discrete circular holes is D. M1 The distance between adjacent discrete circular holes in each row is D.M2 , where D M1 <D L1 D M2 <D L2 ; The development zone of the swirl combustion chamber flame tube has N rows of shallow slots equidistantly spaced along the axial direction. The shallow slots are at an incident angle to the flow direction of the cooling medium in the axial direction, and N is a natural number greater than or equal to 2. As a further optimization of the swirling combustion chamber flame tube that can be efficiently cooled according to the present invention, the incident angles of the L-row discrete circular holes in the vortex zone, the M-row discrete circular holes in the impact zone, and the N-row shallow groove holes in the development zone are all 15°-75°.

[0007] As a further optimization of the swirling combustion chamber flame tube that can be efficiently cooled according to the present invention, the groove depth of the shallow slot is 0.5-1 times the diameter of the shallow slot, and the groove width is 2-3 times the diameter of the shallow slot.

[0008] As a further optimization of the swirling combustion chamber flame tube capable of efficient cooling according to the present invention, the D L2 It is 6-8 times the diameter of the discrete circular holes in the vortex region; D M2 Let the diameter of the discrete circular holes in the impact zone be 3-4 times; let the distance between adjacent shallow slots in each row be D. N2 Then D N2 It is 8-10 times the diameter of the shallow slot.

[0009] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects: 1. Based on the flow characteristics of the swirl combustion chamber, the cooling structure is designed in zones: discrete circular holes are used in the vortex zone; denser discrete circular holes are used in the impact zone to increase the heat exchange in the film cooling holes and reduce the wall temperature of the high heat load impact zone; shallow slots with larger spacing between film cooling holes are used in the development zone to reduce the amount of cooling air used and improve the film cooling efficiency. 2. Under the same cooling air volume, it can effectively improve the film cooling efficiency; 3. Under the same flame tube pressure drop, the amount of cooling gas used can be effectively reduced. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the flow principle in a swirl combustion chamber. Figure 2 This is a schematic diagram of the structure of the present invention.

[0011] In the diagram, 1 represents the angular vortex region, 2 represents the impact region, and 3 represents the development region. Detailed Implementation

[0012] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings: This invention can be implemented in many different forms and should not be considered limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully express the scope of the invention to those skilled in the art. In the drawings, components are enlarged for clarity.

[0013] To better illustrate the working principle of this patent, in conjunction with Figure 1 The typical flow characteristics within a swirling combustion chamber are described. After passing through the swirler, the airflow forms a high-speed rotating jet, creating an inner shear layer (ISL) and an outer shear layer (OSL). Under the influence of centrifugal force and pressure difference, a recirculation zone (MRZ) is formed downstream, and under the influence of the reverse pressure gradient, a lower-velocity, opposite-directional angular recirculation zone (CRZ) is formed. Due to the limited height of the flame tube, the swirling flow in the impact zone (IZ) stagnates at the wall and then abruptly changes direction, flowing at high speed along the wall. As the axial distance increases, the mainstream flow in the development zone (DZ) becomes horizontal to the wall.

[0014] like Figure 2 As shown, the present invention discloses a swirl combustion chamber flame tube capable of efficient cooling, wherein the tube wall of the swirl combustion chamber flame tube is a plate-shaped component that withstands a high-temperature heat source; The vortex region of the flame tube in the swirl combustion chamber has L rows of discrete circular holes equidistantly spaced along the axial direction, each hole forming an incident angle with the direction of the mainstream combustion gas. L is a natural number greater than or equal to 2, and the distance between adjacent rows of L discrete circular holes is D. L1 The distance between adjacent discrete circular holes in each row is D. L2 ; The swirl combustion chamber flame tube has M rows of discrete circular holes equidistantly spaced along the axial direction in the impact zone. These holes form an incident angle with the flow direction of the cooling medium. M is a natural number greater than or equal to 2, and the distance between adjacent rows of the M rows of discrete circular holes is D. M1 The distance between adjacent discrete circular holes in each row is D. M2 , where D M1 <D L1 D M2 <D L2 ; The development zone of the swirl combustion chamber flame tube has N rows of shallow slots equidistantly spaced along the axial direction. The shallow slots are at an incident angle to the flow direction of the cooling medium in the axial direction, and N is a natural number greater than or equal to 2. The incident angles of the L-row discrete circular holes in the vortex region, the M-row discrete circular holes in the impact region, and the N-row shallow slots in the development region are all 15°-75°.

[0015] The shallow slot has a circular inlet and a slotted structure at the outlet that extends along the longitudinal direction. The slot depth is 0.5-1 times the diameter of the shallow slot, and the slot width is 2-3 times the diameter of the shallow slot.

[0016] The D L2 It is 6-8 times the diameter of the discrete circular holes in the vortex region; D M2 Let the diameter of the discrete circular holes in the impact zone be 3-4 times; let the distance between adjacent shallow slots in each row be D. N2 Then D N2 It is 8-10 times the diameter of the shallow slot.

[0017] This invention suppresses the influence of swirling flow, improves the temperature uniformity of the flame tube surface, and enhances the film cooling effect by arranging film holes with different spacing and shapes at different positions of the swirling combustion chamber flame tube. For the angular vortex region, where the heat load is relatively small, discrete circular holes with larger spacing are arranged to reduce processing costs and cooling air consumption. For the impact region, where the heat load is relatively large, discrete circular holes with smaller spacing are arranged to increase the amount of cooling air in the impact region and increase the heat exchange within the film holes, thereby reducing the flame tube wall temperature in the high-heat-load impact region and minimizing temperature non-uniformity. For the development region, shallow slot holes with larger spacing are used to reduce the average exit velocity, improve film adhesion to the wall, and simultaneously increase the coverage effect of the film holes in the spanwise direction, reducing cooling air consumption while improving cooling efficiency.

[0018] In this invention, the shape of the tube wall of the swirl combustion chamber flame tube is not limited; it can be either a flat surface or a curved surface.

[0019] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0020] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific 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 within the protection scope of the present invention.

Claims

1. A swirling combustion chamber flame tube capable of efficient cooling, wherein the tube wall of the swirling combustion chamber flame tube is a plate-shaped component that withstands a high-temperature heat source, characterized in that: The vortex region of the flame tube in the swirl combustion chamber has L rows of discrete circular holes equidistantly spaced along the axial direction, each hole forming an incident angle with the direction of the mainstream combustion gas. L is a natural number greater than or equal to 2, and the distance between adjacent rows of L discrete circular holes is D. L1 The distance between adjacent discrete circular holes in each row is D. L2 ; The swirl combustion chamber flame tube has M rows of discrete circular holes equidistantly spaced along the axial direction in the impact zone. These holes form an incident angle with the flow direction of the cooling medium. M is a natural number greater than or equal to 2, and the distance between adjacent rows of the M rows of discrete circular holes is D. M1 The distance between adjacent discrete circular holes in each row is D. M2 , where D M1 <D L1 D M2 <D L2 ; The development zone of the swirl combustion chamber flame tube has N rows of shallow slots equidistantly spaced along the axial direction. The shallow slots are at an incident angle to the flow direction of the cooling medium in the axial direction, and N is a natural number greater than or equal to 2.

2. The swirl combustion chamber flame tube capable of efficient cooling according to claim 1, characterized in that, The incident angles of the L-row discrete circular holes in the vortex region, the M-row discrete circular holes in the impact region, and the N-row shallow slots in the development region are all 15°-75°.

3. The swirl combustion chamber flame tube capable of efficient cooling according to claim 1, characterized in that, The depth of the shallow slot is 0.5-1 times the diameter of the shallow slot, and the width of the slot is 2-3 times the diameter of the shallow slot.

4. The swirl combustion chamber flame tube capable of efficient cooling according to claim 1, characterized in that, The D L2 It is 6-8 times the diameter of the discrete circular holes in the vortex region; D M2 Let the diameter of the discrete circular holes in the impact zone be 3-4 times; let the distance between adjacent shallow slots in each row be D. N2 Then D N2 It is 8-10 times the diameter of the shallow slot.

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