An integrated two-stage axial cyclone

Abstract

The application discloses an integrated double-stage axial cyclone, which comprises a combination body and a single double-stage axial cyclone; the combination body comprises a connecting support and fixing holes formed on the connecting support; a plurality of single double-stage axial cyclones are fixed on the connecting support in a circumferential array, and each single double-stage axial cyclone is inclined to the central axis of the combination body by 5-10 degrees, so that the integrated double-stage axial cyclone can enhance the central combustion effect when being used in a single combustion chamber of an aero-engine and an industrial gas turbine; the inlet side and the inner ring wall side of the combination body are respectively provided with fixing holes in a circumferential array and consistent with the number of the single double-stage axial cyclones, and the fixing holes are used for fixing the inner and outer sleeves in the combustion chamber. The application is suitable for a small aero-engine combustion chamber, improves the integration and functionality of the device, and is simple in overall manufacturing and installation, light in weight and low in cost.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine combustion chamber technology, specifically relating to an integrated two-stage axial vortex generator. Background Technology

[0002] Swirlers are key components affecting the flow organization of aero-engine combustors. To stabilize the flame in high-speed airflow and improve efficiency while reducing emissions by enhancing fuel atomization, the design of combined systems of two-stage swirlers, venturi tubes, and centrifugal nozzles for air atomization flame tubes is widely used in modern aero-engine combustors. Among these, two-stage axial swirlers are more widely used in combustor design due to their excellent overall combustion performance. Besides meeting flow, atomization, and combustion performance requirements, swirlers must also consider their own machining and assembly, as well as their docking and fixing with components such as the combustor head, flame tube, and fuel nozzles. Currently, traditional machining and CNC machining are time-consuming, costly, and inefficient. This is especially problematic in small aero-engine combustors where space is limited, making assembly difficult and cumbersome. Furthermore, the current swirler structures differ significantly between annular and single-chamber combustor structures, resulting in limited applicability. Summary of the Invention

[0003] The purpose of this invention is to provide an integrated two-stage axial cyclone separator. This device has high integration and strong functionality. It adopts a dual-channel cyclone method, which effectively ensures the fuel atomization effect and the recirculation intensity of the recirculation zone. The first and second stage cyclone blade channels are independent of each other, which can avoid mutual disturbance of the gas in the channels. This cyclone separator can be applied to both annular combustion chamber and single combustion chamber structures of aero engines and industrial gas turbines, and is especially suitable for small aero engine combustion chambers.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] An integrated two-stage axial cyclone separator includes a combined unit and a single two-stage axial cyclone separator;

[0006] The assembly includes a connecting bracket and fixing holes opened on the connecting bracket. Several single-unit double-stage axial swirlers arranged in a circular array are fixed on the connecting bracket, and each single-unit double-stage axial swirler is tilted 5°-10° toward the central axis of the assembly, so that the integrated double-stage axial swirler enhances the central combustion effect when used in the single combustion chamber of aero engines and industrial gas turbines.

[0007] The inlet side and inner ring wall side of the assembly are respectively provided with fixing holes in a circumferential array, which are the same number as the single-unit two-stage axial cyclone separator. The fixing holes are used to fix the inner and outer sleeves of the combustion chamber.

[0008] A further improvement of the present invention is that the integrated two-stage axial vortex generator can also be installed in the annular combustion chamber of aero engines and industrial gas turbines.

[0009] A further improvement of the present invention is that the single-unit two-stage axial cyclone includes a first-stage cyclone blade, a second-stage cyclone blade, a first-stage connecting ring, a second-stage connecting ring, a second-stage cyclone inlet, a nozzle sleeve, and a venturi tube.

[0010] The nozzle sleeve is positioned at the center of the single-unit two-stage axial cyclone separator to fix the nozzle. The first-stage cyclone blade is fixed between the nozzle sleeve and the first-stage connecting ring, and the second-stage cyclone blade is fixed between the first-stage connecting ring and the second-stage connecting ring. The second-stage connecting ring connects the assembly and the second-stage cyclone blade. The first-stage and second-stage cyclone blades enable the fuel and air to mix thoroughly and form a stable backflow zone at the center. The second-stage cyclone inlet is located on the outside of the second-stage cyclone blade. The venturi tube is located at the outlet of the first-stage cyclone blade and the nozzle to improve fuel atomization and prevent fuel backflow from causing coking and carbon buildup on the nozzle.

[0011] A further improvement of the present invention is that the secondary swirl inlet is a square inlet hole.

[0012] A further improvement of the present invention is that in each single-unit two-stage axial cyclone, 3 / 4 of the airflow enters the combustion chamber through the second-stage cyclone inlet and the second-stage cyclone blades, while 1 / 4 of the airflow flows through the first-stage cyclone blades and enters the combustion chamber through the venturi tube.

[0013] A further improvement of the present invention is that the installation angle of the first-stage swirl blade is 55° and the installation angle of the second-stage swirl blade is 45°, which is used to increase the tangential velocity, increase the swirl number, thereby ensuring fuel atomization and the recirculation intensity of the recirculation zone, and improving combustion stability.

[0014] A further improvement of the present invention is that the flow rate ratio of the primary swirl vane to the secondary swirl vane channel is 1:3.

[0015] A further improvement of the invention is that the venturi tube can create a low-pressure zone at its narrow section, which adsorbs the surrounding fuel and air, thereby increasing fuel atomization and mixing.

[0016] A further improvement of the present invention is that the entire integrated two-stage axial cyclone is made of titanium alloy or ceramic 3D printing.

[0017] A further improvement of the present invention is that the fixing hole has threads, and is fixed to the inner and outer sleeves of the combustion chamber by countersunk screws.

[0018] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0019] The integrated two-stage axial cyclone separator provided by this invention has a first-stage blade angle of 55° and a second-stage blade angle of 45°, which can increase the tangential velocity and the number of swirls, thereby ensuring the fuel atomization effect and the recirculation intensity in the recirculation zone, and improving combustion stability. The flow rate ratio of the first-stage blade channel to the second-stage channel is 1:3, so the airflow entering the first and second-stage swirl channels is undisturbed. The second-stage swirl can effectively improve the cooling characteristics of the combustion chamber flame tube wall and avoid erosion of the combustion chamber flame tube wall.

[0020] This invention uses titanium alloy or ceramic 3D printing, which can be directly applied to the annular combustion chamber structure. The overall manufacturing and installation are simple, avoiding the complexity of assembling multiple parts. It can meet the requirements of lightweight design, high structural strength, long service life and low cost.

[0021] This invention can also be directly applied to a single combustion chamber structure, wherein the central axis of each individual dual-stage axial cyclone is deflected 5°-10° toward the center of the integrated dual-stage axial cyclone, which is beneficial to improve the central combustion effect of the single combustion chamber, significantly improve the wall cooling characteristics, and extend the service life of the combustion chamber.

[0022] In summary, this invention is applicable to the field of aero-engine and industrial gas turbine combustors, improving the versatility and flexibility of swirlers. It is particularly suitable for small aero-engine combustors, effectively solving the problems of limited space and difficult installation in small combustors, achieving the lightweight requirements of small aero-engines, and proposing a new solution for the application of two-stage swirlers in aero-engine combustors and other fields. Attached Figure Description

[0023] Figure 1 This is an overall diagram of an integrated two-stage axial cyclone separator according to the present invention;

[0024] Figure 2 This is a front view of an integrated two-stage axial cyclone separator according to the present invention;

[0025] Figure 3 This is a rear view of an integrated two-stage axial cyclone separator according to the present invention;

[0026] Figure 4 This is a cross-sectional view of an integrated two-stage axial cyclone separator as described in this invention.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1-Assembly, 2-Single two-stage axial cyclone separator, 3-Connecting bracket, 4-Fixing hole, 5-Secondary cyclone inlet, 6-Secondary cyclone blade, 7-Nozzle sleeve, 8-Venturi tube, 9-First-stage cyclone blade, 10-First-stage connecting ring, 11-Secondary connecting ring. Detailed Implementation

[0029] The specific implementation methods of the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] like Figures 1 to 4 As shown, the present invention provides an integrated two-stage axial cyclone separator, comprising a composite body 1 and seven individual two-stage axial cyclones 2. The composite body 1 includes a connecting bracket 3 and fixing holes 4, the fixing holes 4 being disposed on the inner annular wall and the front side of the connecting bracket 3; the individual two-stage axial cyclones 2 include a secondary cyclone inlet 5, a secondary cyclone blade 6, a nozzle sleeve 7, a venturi tube 8, a primary cyclone blade 9, a primary connecting ring 10, and a secondary connecting ring 11, all integrally manufactured using titanium alloy or ceramic 3D printing, featuring high structural strength, integrated molding, and lightweight design.

[0031] To better understand the present invention, the various structures of the present invention are described below.

[0032] like Figures 1 to 3 As shown, this invention provides an integrated two-stage axial cyclone separator, comprising multiple individual two-stage axial cyclones 2 and a connecting bracket 3. The connecting bracket 3 serves to fix the individual two-stage axial cyclones 2 together and to position them at a certain tilt angle. Each individual two-stage axial cyclone separator 2 is composed of two nested cyclone channels, which can generate a strong swirling effect, ensuring thorough mixing and combustion of fuel and air. The assembly 1 contains seven individual two-stage axial cyclones 2, evenly distributed along the circumference to form an annular combustion zone. To achieve more uniform and stable combustion, each individual two-stage axial cyclone separator 2 is tilted 5°-10° towards the central axis of the assembly 1, which increases the central temperature of the combustion zone while reducing the heat load on the combustion chamber walls. There are seven fixing holes 4 on the inlet side and inner ring wall of the assembly 1, which correspond to the position of the single-unit double-stage axial cyclone 2. The fixing holes 4 have threads, and the assembly 1 can be connected to the inner and outer sleeves of the combustion chamber flame tube by countersunk screws. In addition, the assembly is provided with a limit end face to ensure that the position and angle of the assembly 1 will not change.

[0033] like Figures 2 to 4As shown, the single-stage dual-stage axial swirler 2 consists of a secondary swirling inlet 5, secondary swirling blades 6, a nozzle sleeve 7, a venturi tube 8, a primary swirling blade 9, a primary connecting ring 10, and a secondary connecting ring 11. The primary swirling blade 9 is a group of five helical blades arranged circumferentially. Their shape and angle generate a strong swirling flow of the incoming air, thereby increasing the contact area and mixing degree between air and fuel, and improving combustion efficiency. The primary swirling blade 9 is fixed between the nozzle sleeve 7 and the primary connecting ring 10, forming an annular space, which is part of the swirling region. The secondary swirling blades 6 are another group of five helical blades arranged circumferentially. Their shape and angle are opposite to those of the primary swirling blades 9, which generate a swirling flow of the incoming air in the opposite direction to that of the primary swirling blades 9, thereby forming a stable recirculation zone at the center. This recirculation zone maintains the continuity and stability of combustion and also forms a gas film on the flame tube wall, reducing the combustion chamber wall temperature. The secondary swirl blade 6 is fixed between the primary connecting ring 10 and the secondary connecting ring 11, forming an annular space, which is another part of the swirl region. The primary connecting ring 10 is annular and its function is to connect the primary swirl blade 9 and the secondary swirl blade 6, while also providing support and fixation to ensure the structural stability of the swirler. The secondary connecting ring 11 is annular and its function is to connect the secondary swirl blade 6 and the secondary swirl inlet 5, while also providing support and fixation to ensure the structural stability of the swirler. The secondary swirl inlet 5 is a square inlet hole, its function is to supply air to the channel of the secondary swirl blade 6, thereby forming the second-stage swirl effect. The secondary swirl inlet 5 is located outside the secondary swirl blade 6, separated from the primary swirl inlet by a certain distance and independent of each other, thus avoiding interference between the primary and secondary swirls and improving stability. The nozzle sleeve 7 functions to fix the nozzle, allowing the nozzle to inject fuel towards the center of the swirler, thereby mixing and burning with air. The nozzle sleeve 7 is positioned at the center of the cyclone separator, closely fitting against the first-stage cyclone blade 9 to form a closed space, which is the innermost part of the combustion zone. The venturi tube 8 is a throat-shaped component located at the outlet between the first-stage cyclone blade 9 and the nozzle, forming a channel that first narrows and then expands. This channel increases fuel atomization and mixing, improves combustion efficiency, reduces emissions, and prevents fuel backflow into the nozzle, causing erosion and carbon buildup, thereby extending the service life of the nozzle and the cyclone separator.

[0034] like Figure 4As shown, both the first-stage swirl blade 9 and the second-stage swirl blade 6 have a fixed installation angle, i.e., the angle between the blade and the axis. The size of the installation angle affects the intensity and direction of the swirl generated by the swirler, thus affecting the flow field and combustion characteristics inside the combustion chamber. Through comparative experiments, it was found that when the installation angle of the first-stage swirl blade 9 is 55° and the installation angle of the second-stage swirl blade 6 is 45°, a better combustion effect can be achieved. This is because this angle combination allows two swirls in opposite directions to be generated inside the combustion chamber, increasing the contact area between the fuel and the airflow, and forming a stable recirculation zone in the center. This recirculation zone can maintain the continuity and stability of combustion, while also playing a cooling role, reducing the temperature of the combustion chamber. Furthermore, this angle combination can also increase the tangential velocity, increase the swirl number, and thus improve the fuel atomization effect, making the fuel finer and more uniform, thereby improving combustion efficiency.

[0035] like Figure 2 and Figure 3 As shown, the first-stage swirl vane 9 and the second-stage swirl vane 6 form the first-stage and second-stage swirl channels, respectively, to supply air to the combustion chamber. The flow rate ratio of the first-stage swirl vane 9 channel to the second-stage swirl vane 6 channel is 1:3, meaning the area of ​​the first-stage swirl vane 9 channel is one-third the area of ​​the second-stage swirl vane 6 channel. This flow rate ratio provides sufficient cooling air to the second-stage swirl vane channel, enhancing the airflow over the combustion chamber walls and forming a cooling film on the combustion chamber walls. This effectively isolates the high-temperature combustion gases from the combustion chamber walls, preventing excessive heat load on the combustion chamber walls, significantly improving the cooling characteristics of the combustion chamber walls, and extending the lifespan of the combustion chamber.

[0036] like Figure 4 As shown, the Venturi tube 8 is a device that utilizes the transition of airflow from coarse to fine to accelerate the gas flow rate and create a low-pressure zone. When fuel passes through the Venturi tube 8, the outer ring of the Venturi tube 8 outlet has a lower air pressure than the surrounding atmosphere, causing it to draw in surrounding air, thus ensuring thorough mixing of fuel and air, increasing fuel atomization, and improving combustion efficiency. Simultaneously, the low-pressure zone of the Venturi tube 8 also prevents fuel backflow at the nozzle, avoiding fuel erosion and carbon buildup on the nozzle, and extending the nozzle's service life.

[0037] like Figures 1 to 4As shown, this invention provides an integrated two-stage axial swirler, a device for generating high-efficiency combustion. It consists of seven equidistantly arranged individual two-stage axial swirlers 2, each with a separate primary and secondary swirling channel for introducing air and generating swirl. This invention is manufactured using titanium alloy or ceramic 3D printing and can be directly installed on the annular combustion chamber of aero-engines and industrial gas turbines, forming a continuous swirler array. This simplifies the overall structure and manufacturing process of the combustion chamber, reduces the number of parts and assembly difficulty, and is particularly suitable for small aero-engine combustion chambers with compact internal space and difficult installation. Compared with traditional manufacturing methods, the overall manufacturing and installation are simple, meeting lightweight design requirements, with high structural strength, long service life, and low cost. Furthermore, this invention is also applicable to single-combustion-chamber aero-engines and industrial gas turbines, improving the versatility and flexibility of the swirler. The central axis of each individual two-stage axial swirler 2 is deflected towards the center by 5°-10°, which improves the central combustion effect of the single combustion chamber, enhances combustion stability and uniformity, and also reduces the temperature and thermal stress of the combustion chamber wall.

[0038] This invention provides an integrated two-stage axial swirler suitable for use in aero-engine and industrial gas turbine combustors. It can be directly applied to annular and single combustors, exhibiting central combustion flame characteristics in aero-engine and industrial gas turbine single combustors. This significantly improves the cooling characteristics of the combustor walls and extends the service life of the combustor. Furthermore, this invention is particularly suitable for small aero-engines, effectively solving problems such as limited internal space and installation difficulties in small combustors, and meeting the lightweight requirements of small aero-engines. It provides a new solution for the application of two-stage swirlers in aero-engine combustors and other applications.

[0039] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and design concept of the present invention, should be included within the scope of protection of the present invention.

Claims

1. An integrated two-stage axial cyclone, characterized by, The integrated dual-stage axial cyclone separator is made entirely of titanium alloy or ceramic 3D printing, including the combined body and the individual dual-stage axial cyclone separator; The assembly includes a connecting bracket and fixing holes opened on the connecting bracket. Several single-unit double-stage axial swirlers arranged in a circular array are fixed on the connecting bracket, and each single-unit double-stage axial swirler is tilted 5°-10° toward the central axis of the assembly, so that the integrated double-stage axial swirler enhances the central combustion effect when used in the single combustion chamber of aero engines and industrial gas turbines. The inlet side and inner ring wall side of the assembly are respectively provided with fixing holes in a circumferential array, which are the same number as the single-unit two-stage axial cyclone separator. The fixing holes are used to fix the inner and outer sleeves of the combustion chamber. The single-unit two-stage axial cyclone separator includes a first-stage cyclone blade, a second-stage cyclone blade, a first-stage connecting ring, a second-stage connecting ring, a second-stage cyclone inlet, a nozzle sleeve, and a venturi tube; The nozzle sleeve is positioned at the center of the single-unit two-stage axial cyclone separator to fix the nozzle; the first-stage cyclone blades are fixed between the nozzle sleeve and the first-stage connecting ring, and the second-stage cyclone blades are fixed between the first-stage and second-stage connecting rings, with the second-stage connecting ring connecting the assembly and the second-stage cyclone blades; the first-stage and second-stage cyclone blades enable the fuel and air to mix thoroughly and form a stable backflow zone at the center; the second-stage cyclone inlet is located outside the second-stage cyclone blades; the venturi tube is located at the outlet of the first-stage cyclone blades and the nozzle to improve fuel atomization and prevent fuel backflow from causing coking and carbon buildup on the nozzle; In each single-unit two-stage axial cyclone separator, 3 / 4 of the airflow enters the combustion chamber through the second-stage cyclone inlet and the second-stage cyclone blades, while 1 / 4 of the airflow flows through the first-stage cyclone blades and enters the combustion chamber through the venturi tube. The first-stage swirl vanes are installed at an angle of 55°, and the second-stage swirl vanes are installed at an angle of 45°. This is used to increase the tangential velocity, increase the swirl number, and thus ensure fuel atomization and the recirculation intensity of the recirculation zone, thereby improving combustion stability. This integrated two-stage axial vortex generator is also used in the annular combustion chambers of aircraft engines and industrial gas turbines.

2. An integrated two-stage axial cyclone according to claim 1, wherein, The secondary swirl inlet is a square air inlet.

3. The one-piece two-stage axial cyclone of claim 1, wherein, The flow rate ratio between the first-stage swirl vane and the second-stage swirl vane channel is 1:

3.

4. The one-piece two-stage axial cyclone of claim 1, wherein, The venturi tube creates a low-pressure zone at its narrowest point, drawing in surrounding fuel and air, thus increasing fuel atomization and mixing.

5. The one-piece two-stage axial cyclone of claim 1, wherein, The fixing hole has threads and is fixed to the inner and outer sleeves of the combustion chamber by countersunk screws.

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