Round and elliptic composite configuration double swirler matched with swirling trapped vortex combustion chamber

Abstract

The invention discloses a circular and elliptic composite configuration double cyclone matched with a cyclone trapped vortex combustion chamber. The circular and elliptic composite configuration double cyclone comprises an inner cylinder, a middle cylinder, an outer cylinder, a venturi tube, N1 first blades and N2 second blades, the inner cylinder is a solid cylinder, the middle cylinder is a hollow cylinder, and the outer fixed cylinder is a hollow elliptic cylinder; the N1 first blades are uniformly arranged between the outer cylinder and the middle cylinder in the circumferential direction, and the N2 second blades are uniformly arranged between the inner cylinder and the middle cylinder in the circumferential direction, so that the inner cylinder, the middle cylinder and the outer cylinder are coaxially arranged from inside to outside; and the upstream of the venturi tube is coaxially and fixedly connected with the downstream of the middle cylinder, and the venturi tube is used for promoting crushing and atomization of fuel oil. According to the invention, gas is swirled through the first-stage circular swirler to generate an on-duty stable backflow area so as to ensure the stability of on-duty flames; meanwhile, through the two-stage oval swirler, high-speed rotating jet flow is generated in a main combustion area of the head of the combustion chamber, oil and gas mixing is promoted, and the structure of the novel trapped vortex combustion chamber is matched with that of the novel trapped vortex combustion chamber on the basis of guaranteeing flame stability.

Description

Technical Field

[0001] This invention relates to the field of swirl technology for combustion chamber structures, and more particularly to a circular-elliptical composite configuration dual swirler that matches a swirling vortex combustion chamber. Background Technology

[0002] With the further development of aero-engine technology, the thrust-to-weight ratio is constantly increasing, and the demand for higher thrust is leading to increasingly higher fuel-to-air ratios in the combustion chamber, requiring a correspondingly larger volume of air for combustion. To avoid smoke in the combustion chamber, advanced combustion chamber designs incorporate a significant portion of the air entering the combustion chamber through a head swirler. To achieve this design philosophy of larger head air intake, head swirler designs have evolved from early single-stage swirlers to multi-stage swirlers. Employing a multi-stage swirler combustion organization method has become an effective solution to overcome the technological bottlenecks of high-performance combustion chambers.

[0003] Swirlers are commonly used in aircraft engine combustion chambers to stabilize the flame. After entering the flame tube through the swirler, the airflow forms a rotating airflow with axial, radial, and circumferential velocities. Due to air viscosity, the gas at the center of the flame tube is carried away by the high-speed jet, creating a low-pressure zone and establishing a stable recirculation zone to maintain flame stability. In addition, the high-speed rotating jet increases the relative velocity between the airflow and fuel droplets, thereby improving fuel-air mixing. Simultaneously, the swirler can also serve as an airflow channel for pneumatic atomizing nozzles, providing an appropriate amount of air to the nozzle head to ensure a certain residual gas coefficient.

[0004] With the development of engine combustion chambers, a new type of staged and zoned combustion vortex combustion chamber has emerged. This combustion chamber is divided into a main combustion stage and a booster stage (cavity). The booster stage is used to stabilize the flame. Simultaneously, in low-pressure conditions, only the booster stage is used for fuel supply; in high-pressure conditions, both the booster stage and the main combustion stage simultaneously provide power to the engine. Most existing vortex main combustion chambers adopt a slotted or duct-type mainstream intake structure. The high air velocity in the main combustion zone makes it difficult to supply fuel in the mainstream zone, thus hindering staged fuel supply and improving engine performance. Therefore, applying swirl technology to the vortex combustion chamber to obtain a main combustion stage head with good fuel-air mixing, long airflow residence time, stable operation of both stages, a compact structure, and high space utilization has become an effective solution to improve combustion chamber performance. However, the problem of matching the radial dimensions of the head cavity structure with the swirler structure is difficult to solve. To ensure that the head structure can meet the stable combustion requirements of the main combustion stage and the booster stage, it is necessary to invent a swirler that can be adapted to the vortex combustion chamber. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to address the deficiencies mentioned in the background art by providing a spherical-elliptical composite configuration dual vortex generator that matches a swirl-stabilized combustion chamber.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A circular-elliptical composite configuration dual vortex generator that matches a vortex combustion chamber includes an inner cylinder, a middle cylinder, an outer cylinder, a venturi tube, N1 first blades, and N2 second blades, where N1 and N2 are both natural numbers greater than or equal to 3.

[0008] The inner cylinder is a solid cylinder, the middle cylinder is a hollow cylinder with openings at both ends, and the outer fixed cylinder is a hollow elliptical cylinder with openings at both ends.

[0009] The N1 first blades are circumferentially evenly arranged between the outer cylinder and the middle cylinder, and the N2 second blades are circumferentially evenly arranged between the inner cylinder and the middle cylinder, so that the inner cylinder, the middle cylinder and the outer cylinder are coaxially arranged from the inside to the outside.

[0010] The Venturi tube is a cylinder with a through hole along its axis. Its outer diameter is the same as that of the middle cylinder, and its inner diameter gradually decreases and then gradually increases from upstream to downstream. The upstream of the Venturi tube and the downstream of the middle cylinder are coaxially fixed together to promote the atomization and breakup of fuel.

[0011] The installation angles of the N1 first blades are all preset first angle thresholds β1, and the spacing angles between adjacent first blades are all preset second angle thresholds α1; the installation angles of the N2 second blades are all preset third angle thresholds β2, and the spacing angles between adjacent second blades are preset fourth angle thresholds α2.

[0012] As a further optimization of the elliptical composite configuration dual vortex generator that matches the vortex combustion chamber of the present invention, N1 ranges from 10 to 20, and N2 ranges from 16 to 24.

[0013] As a further optimization of the elliptical composite configuration dual vortex generator for matching the vortex combustion chamber of the present invention, the major semi-axis of the flow section of the outer cylinder is set to R. a The minor semi-axis is R b Then R a With R b The ratio ranges from 1.4 to 2.

[0014] As a further optimization of the elliptical composite configuration dual vortex generator for matching the vortex combustion chamber of this invention, the inner diameter of the middle cylinder is r2; the minor semi-axis of the flow section of the outer cylinder is R. b r2 and R b The ratio ranges from 0.4 to 0.8.

[0015] As a further optimization of the elliptical composite configuration dual vortex generator that matches the vortex combustion chamber of the present invention, the ranges of β1 and β2 are both 30°-75°.

[0016] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects:

[0017] This invention utilizes a primary circular swirler to swirl the gas, creating a stable recirculation zone to ensure flame stability during the main combustion stage. Simultaneously, a secondary elliptical swirler generates a high-speed rotating jet in the main combustion zone at the combustion chamber head, promoting fuel-air mixing and ensuring flame stability. This is further complemented by a novel vortex combustion chamber structure. This invention solves the problem of short radial length at the head of compact vortex combustion chambers, providing a reliable low-pressure recirculation zone for the main combustion stage of the flame tube, achieving dual-stage fuel supply, and ensuring that the head structure can meet the requirements for stable combustion in both the main combustion stage and the main combustion stage. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 This is a structural cross-sectional view of the central section of the present invention;

[0020] Figure 3 This is a schematic diagram of the structural parameters of the present invention;

[0021] Figure 4 This is a schematic diagram of the structural parameters of the first blade on the inner cylinder in this invention;

[0022] Figure 5 This is a schematic diagram of the structural parameters of the second blade on the middle cylinder in this invention;

[0023] Figure 6 This is a schematic diagram of the structure of the present invention applied in the combustion chamber.

[0024] In the diagram, 1-inner cylinder, 2-middle cylinder, 3-outer cylinder, 4-first blade, 5-second blade, 6-Venturi tube. Detailed Implementation

[0025] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings:

[0026] 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.

[0027] It should be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, and / or parts, these elements, components, and / or parts are not limited by these terms. These terms are merely used to distinguish elements, components, and / or parts from one another. Therefore, the first element, component, and / or part discussed below may be a second element, component, or part without departing from the teachings of this invention.

[0028] In the description of this invention, it should be understood that the terms "horizontal," "vertical," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and should not be construed as limiting this invention; the terms "installation," "connection," "fixing," etc., should be interpreted broadly, for example, they can refer to a fixed connection, a detachable connection, or an integral connection, they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components; for those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0029] Existing swirling vortex main combustion chambers mostly employ a two-stage swirler main intake structure. However, the two-stage swirler structure is complex, and the radial cavity size needs to be reserved, resulting in an excessively large radial dimension at the head. This invention reduces the radial dimension of the combustion chamber head by using a stationary first-stage circular swirler and a second-stage irregularly shaped elliptical swirler to organize the flow field in the main combustion zone. This approach adapts to the technical requirements of compact combustion chambers while increasing the flow area at the combustion chamber head, thereby reducing pressure drop in the combustion chamber.

[0030] like Figure 1 , Figure 2 As shown, the present invention discloses a circular-elliptical composite configuration dual vortex generator that matches a vortex combustion chamber, comprising an inner cylinder, a middle cylinder, an outer cylinder, a venturi tube, N1 first blades, and N2 second blades, where N1 and N2 are both natural numbers greater than or equal to 3;

[0031] The inner cylinder is a solid cylinder, the middle cylinder is a hollow cylinder with openings at both ends, and the outer fixed cylinder is a hollow elliptical cylinder with openings at both ends.

[0032] The N1 first blades are circumferentially evenly arranged between the outer cylinder and the middle cylinder, and the N2 second blades are circumferentially evenly arranged between the inner cylinder and the middle cylinder, so that the inner cylinder, the middle cylinder and the outer cylinder are coaxially arranged from the inside to the outside.

[0033] The Venturi tube is a cylinder with a through hole along its axis. Its outer diameter is the same as that of the middle cylinder, and its inner diameter gradually decreases and then gradually increases from upstream to downstream. The upstream of the Venturi tube and the downstream of the middle cylinder are coaxially fixed together to promote the atomization and breakup of fuel.

[0034] The installation angles of the N1 first blades are all preset first angle thresholds β1, and the spacing angles between adjacent first blades are all preset second angle thresholds α1; the installation angles of the N2 second blades are all preset third angle thresholds β2, and the spacing angles between adjacent second blades are preset fourth angle thresholds α2.

[0035] The range of N1 is 10-20, and the range of N2 is 16-24.

[0036] The inner diameter of the inner cylinder is r1, and the inner diameter of the middle cylinder is r2; the major semi-axis of the flow section of the outer cylinder is R. a The minor semi-axis is R b Then R a With R b The ratio ranges from 1.4 to 2, and r² and R² are related. b The ratio ranges from 0.4 to 0.8. The ranges for both β1 and β2 are 30° to 75°.

[0037] like Figure 3 , Figure 4 and Figure 5 As shown, the installation angles of the N1 first blades are all preset first angle thresholds β1, and the spacing angles between adjacent first blades are all preset second angle thresholds α1; the installation angles of the N2 second blades are all preset third angle thresholds β2, and the spacing angles between adjacent second blades are preset fourth angle thresholds α2.

[0038] The inner cylinder has a length D1 in the flow direction, the middle cylinder and the outer wall of the venturi tube have a length D2 in the flow direction, and the outer cylinder has a length D3 in the flow direction. The positional relationship of the inner cylinder, middle cylinder, and outer cylinder in the flow direction is common knowledge in the art and is set as needed. The length relationship of D1, D2, and D3 is also common knowledge in the art.

[0039] The vertical thickness of the first blade is h1, and the chord length is L1; the vertical thickness of the second blade is h2, and the chord length is L2.

[0040] like Figure 6 As shown, when the TVC radial matching vortex generator is applied to a vortex combustor, it can reduce the radial height of the combustor head while meeting the requirements of mainstream combustion and stable combustion during shifts in the vortex combustor.

[0041] This invention improves the performance of a vortex combustor by applying a circular-elliptical composite configuration dual-swirl head to the vortex combustor, thereby reducing the radial length of the combustor head and increasing the flow area at the combustor head. All parameters in this invention can be appropriately designed and adjusted according to the operating requirements of the combustor.

[0042] 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.

[0043] 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 circular-elliptical composite configuration dual-swirl head for matching a swirling vortex combustion chamber, characterized in that, It includes an inner cylinder, a middle cylinder, an outer cylinder, a venturi tube, N1 first blades, and N2 second blades, where N1 and N2 are both natural numbers greater than or equal to 3; The inner cylinder is a solid cylinder, the middle cylinder is a hollow cylinder with openings at both ends, and the outer fixed cylinder is a hollow elliptical cylinder with openings at both ends. The N1 first blades are circumferentially evenly arranged between the outer cylinder and the middle cylinder, and the N2 second blades are circumferentially evenly arranged between the inner cylinder and the middle cylinder, so that the inner cylinder, the middle cylinder and the outer cylinder are coaxially arranged from the inside to the outside. The Venturi tube is a cylinder with a through hole along its axis. Its outer diameter is the same as that of the middle cylinder, and its inner diameter gradually decreases and then gradually increases from upstream to downstream. The upstream of the Venturi tube and the downstream of the middle cylinder are coaxially fixed together to promote the atomization and breakup of fuel. The installation angles of the N1 first blades are all preset first angle thresholds β1, and the spacing angles between adjacent first blades are all preset second angle thresholds α1; the installation angles of the N2 second blades are all preset third angle thresholds β2, and the spacing angles between adjacent second blades are preset fourth angle thresholds α2.

2. The elliptical composite configuration dual vortex generator with matched vortex combustion chamber according to claim 1, characterized in that, The range of N1 is 10-20, and the range of N2 is 16-24.

3. The elliptical composite configuration dual vortex generator with matched vortex combustion chamber according to claim 1, characterized in that, Let R be the semi-major axis of the flow section of the outer cylinder. a The minor axis is R b Then R a With R b The ratio ranges from 1.4 to 2.

4. The elliptical composite configuration dual vortex generator with matched vortex combustion chamber according to claim 1, characterized in that, Let the inner diameter of the middle cylinder be r2; and the minor semi-axis of the flow section of the outer cylinder be R. b r2 and R b The ratio ranges from 0.4 to 0.

8.

5. The elliptical composite configuration dual vortex generator with matched vortex combustion chamber according to claim 1, characterized in that, The ranges for β1 and β2 are both 30°-75°.

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