Microtube premixed combustor based on edge wing vortex generator

Abstract

The application provides a micro-tube premixed combustor based on a strip wing vortex generator, which comprises a tube body, an air passage and a mixing passage, the mixing passage comprises a main flow section and a branch flow section, the main flow section is communicated with the air passage, the branch flow section is arranged on the side of the main flow section away from the air passage and is communicated with the main flow section, and the flow area of the branch flow section is smaller than that of the main flow section; a fuel pipe, one end of the fuel pipe is inserted into the air passage and is connected with the tube body, the fuel pipe is provided with a fuel passage, and the fuel passage is communicated with the air passage; and a vortex generator, which is arranged in the air passage and is connected with the fuel pipe; wherein the vortex generator is a strip wing vortex generator, which can realize the short-distance and sufficient mixing of hydrogen and air in a low-speed flow field, inhibit and eliminate the formation of local high-temperature hot spots in the combustion zone, greatly limit the generation of combustion nitrogen oxides and realize the hydrogen premixed combustion with ultra-low emission while ensuring low flow loss and anti-backfire performance.

Description

Technical Field

[0001] This invention relates to the field of hydrogen premixed combustion technology, and in particular to a microtube premixed burner based on a wing-shaped vortex generator. Background Technology

[0002] Currently, hydrogen energy, with its high calorific value, zero carbon emissions, and potential for large-scale clean production, has become a key pathway for the energy transition of civil aviation. Compared to traditional aviation fuels, hydrogen has advantages such as lower density, higher adiabatic flame temperature, and faster flame propagation speed. However, hydrogen combustion presents the challenge of mixing with air, leading to localized high-temperature hotspots in the combustion zone and higher nitrogen oxide emissions. Furthermore, premixed hydrogen fuel is highly susceptible to backfire, necessitating the creation of localized high-velocity regions as backfire prevention barriers, which results in significant flow head losses. Summary of the Invention

[0003] This invention provides a microtube premixed burner based on a slat vortex generator to solve the problem of difficult mixing in hydrogen combustion in related technologies. While ensuring low flow loss and anti-backfire performance, it achieves short-distance and thorough mixing of hydrogen and air.

[0004] This invention provides a microtube premixed burner based on a winglet vortex generator, comprising: The pipe body is provided with an air passage and a mixing passage. The mixing passage includes a main flow section and a branch flow section. The main flow section is connected to the air passage. The branch flow section is located on the side of the main flow section away from the air passage and is connected to the main flow section. The flow cross-sectional area of ​​the branch flow section is smaller than that of the main flow section. A fuel pipe, one end of which extends into the air passage and is connected to the pipe body; the fuel pipe is provided with a fuel passage that communicates with the air passage. A vortex generator is located inside the air passage and connected to the fuel pipe; The vortex generator is a strake wing vortex generator.

[0005] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein the splitting section includes a first section and a second section connected together, the first section being farther away from the main flow section than the second section, and the side of the first section opposite to the second section having an outlet; In particular, along the direction closer to the outlet, the flow cross-sectional area of ​​the first segment gradually decreases.

[0006] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein the angle between the extension lines of the inner walls of the first section and the second section is α, wherein 1°≤α≤10°.

[0007] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein the length of the main stream section in the axial direction of the tube body is L1, wherein 15mm≤L1≤80mm; and / or The length of the diversion section along the axial direction of the pipe body is L2, wherein 15mm ≤ L2 ≤ 60mm; and / or The number of diversion sections is n1, where 1≤n1≤12.

[0008] According to the present invention, a microtube premixed burner based on a slat vortex generator is provided, wherein the tube body comprises: The pipe body is provided with the air passage and the mixing passage; A flow guide plate is disposed within the pipe body and located between the air passage and the mixing passage. The flow guide plate extends axially along the pipe body. One end of the flow guide plate is connected to the inner wall of the pipe body, and the other end is connected to the outer wall of the fuel pipe. The outer wall of the fuel pipe, the inner wall of the pipe body, and the flow guide plate enclose a vortex chamber. The air passage communicates with the main flow section through the vortex chamber. Along the axial direction of the tube, the vortex generator is positioned opposite to the vortex chamber.

[0009] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein there are multiple guide plates, and the multiple guide plates are arranged circumferentially along the tube body. Any two adjacent guide plates, the outer wall of the fuel pipe and the inner wall of the tube body enclose a vortex chamber. The tube body contains multiple vortex generators, which are arranged opposite to multiple vortex chambers along the axial direction of the tube.

[0010] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein the distance between the end of the guide plate near the vortex generator and the end of the vortex generator near the guide plate in the axial direction of the tube body is h1, wherein 1mm≤h1≤5mm; and / or The length of the guide plate in the axial direction of the pipe body is L3, wherein 5mm ≤ L3 ≤ 30mm; and / or The number of the flow guide plates is n2, where 2 ≤ n2 ≤ 8; and / or The thickness of the flow guide plate is t1, wherein 0.5mm ≤ t1 ≤ 3mm; and / or The outer diameter of the tube body is D1, wherein 10mm ≤ D1 ≤ 40mm; and / or The wall thickness of the pipe body is t3, wherein 0.5mm ≤ t3 ≤ 5mm; and / or The length of the tube body is L, where 60mm≤L≤200mm.

[0011] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein the guide plate includes a first plate, and the microtube premixed burner is cross-sectioned along an axis perpendicular to the tube body to obtain a first cross-section; Wherein, on the first cross section, the line connecting the rear edge of the eddy current generator away from the center of the fuel pipe to the center of the fuel pipe is the first line, and the angle between the first line and the center line of the first support plate is γ, wherein 15°≤γ≤75°; and / or, on the first cross section, the angle between the center line of the split section passing through the center of the fuel pipe and the center line of the first support plate is θ, wherein 45°≤θ≤135°.

[0012] According to the present invention, a microtube premixed burner based on a slat vortex generator is provided, wherein the microtube premixed burner further comprises: The discharge channel is provided in part of the fuel pipe and communicates with the fuel channel, and the other part of the discharge channel is provided in the eddy current generator; A nozzle is provided in the vortex generator, one end of which is connected to the discharge channel, and the other end of which passes through one side of the vortex generator away from the mixing channel.

[0013] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein the number of nozzles is n3, where 1 ≤ n3 ≤ 4; and / or The diameter of the nozzle is d, where 0.4mm≤d≤1.5mm; and / or the distance between the central axis of the nozzle and the trailing edge of the vortex generator is h2, where 0.5mm≤h2≤3mm.

[0014] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein the discharge channel includes an ejection section disposed in the vortex generator; a second cross-section is obtained by cross-sectioning the vortex generator along its thickness direction; Wherein, on the second cross section, the central axis of the nozzle is perpendicular to the center line of the ejection section; and / or, on the second cross section, the width of the ejection section is a1, wherein 0.6mm≤a1≤1.2mm.

[0015] According to the present invention, a microtube premixed combustor based on a slat vortex generator is provided, wherein the vortex generator comprises: Straight section; The vortex section is connected to the straight section; The nozzle is located in the straight section.

[0016] According to the present invention, a microtube premixed burner based on a wing-shaped vortex generator is provided, wherein the length of the straight section is L4, wherein 0 mm < L4 ≤ 8 mm; and / or The width of the straight section is a2, where 2mm ≤ a2 ≤ 12mm; and / or The eddy current generator includes a connecting end, which is connected to the fuel pipe. The length of the connecting end is L5, wherein 10mm≤L5≤30mm.

[0017] According to the present invention, a microtube premixed burner based on a slat vortex generator is provided, wherein the thickness of the vortex generator is t2, wherein 0.8 mm ≤ t2 ≤ 3.2 mm; and / or The number of eddy current generators is n4, where 1 ≤ n4 ≤ 8; and / or A second cross-section is obtained by cutting the eddy current generator along its thickness direction. On this second cross-section, the angle between the centerline of the eddy current generator and the horizontal plane is β, where 5° ≤ β ≤ 30°; and / or The outer diameter of the fuel pipe is D2, wherein 4mm ≤ D2 ≤ 20mm; and / or The wall thickness of the fuel pipe is t4, where 0.5mm ≤ t4 ≤ 3mm.

[0018] The microtube premixed combustor based on a slat-wing vortex generator provided by this invention induces large-scale "slat-wing vortices" within the air channel by incorporating a slat-wing vortex generator within the air channel. These vortices are stable and can generate strong vortices with relatively low pressure heads. Combined with the reduction in the flow area within the mixing channel to increase the mainstream velocity, this achieves short-distance, thorough mixing of hydrogen and air in a low-velocity flow field while ensuring low flow losses and backfire prevention performance. This overcomes the shortcomings of related technologies where hydrogen and air are difficult to mix. While ensuring uniform hydrogen-air mixing, it suppresses and eliminates the formation of localized high-temperature hotspots in the combustion zone, reduces the volume of the high-temperature zone, and significantly limits the generation of nitrogen oxides during combustion, achieving ultra-low emission hydrogen premixed combustion. Simultaneously, it avoids the high pressure loss caused by long-distance, high-speed mainstream flow and provides a high-velocity backfire prevention barrier at the premixing nozzle, thus combining backfire prevention and low-pressure-loss premixing tube design into one, while also considering the safe operation and energy consumption of the microtube premixed combustor. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is one of the structural schematic diagrams of the microtube premixed burner provided by the present invention.

[0021] Figure 2 This is the second schematic diagram of the microtube premixed burner provided by the present invention.

[0022] Figure 3 This is the third schematic diagram of the microtube premixed burner provided by the present invention.

[0023] Figure 4 This is the fourth schematic diagram of the microtube premixed burner provided by the present invention.

[0024] Figure 5 This is the fifth schematic diagram of the microtube premixed burner provided by the present invention.

[0025] Figure 6 This is the sixth schematic diagram of the microtube premixed burner provided by the present invention.

[0026] Figure 7 This is one of the structural schematic diagrams of the eddy current generator provided by the present invention.

[0027] Figure 8 This is the second schematic diagram of the eddy current generator provided by the present invention.

[0028] Figure label: 1: Microtube premixed burner; 10: Tube body; 12: Air passage; 14: Mixing passage; 141: Main stream section; 142: Diversion section; 143: First section; 144: Second section; 145: Outlet; 16: Tube body; 18: Guide plate; 19: First support plate; 20: Fuel pipe; 22: Fuel passage; 30: Vortex generator; 32: Straight section; 34: Vortex section; 36: Connecting end; 38: Trailing edge; 40: Vortex chamber; 50: Discharge passage; 52: Spray section; 60: Nozzle; 70: First line. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0030] Currently, with the increasing severity of global climate change, carbon emission reduction and energy structure transformation have become core strategies for the development of the aviation industry. Hydrogen energy, with its high calorific value, zero carbon emissions, and potential for large-scale clean production, has become a key path for civil aviation to achieve energy transformation. Compared to traditional aviation fuels, hydrogen has advantages such as low density, high adiabatic flame temperature, and fast flame propagation speed. However, hydrogen combustion presents challenges such as difficulty in mixing and high nitrogen oxide emissions. Hydrogen micro-premixed combustion technology uses microchannels to confine fuel and air within a very small area for mixing, forming many isolated premixed microscale flames.

[0031] To achieve thorough mixing of hydrogen and air, various mixing methods have been employed in related technologies. These include geometrical flow-disrupting structures such as helical blades, multi-stage swirl blades, and static mixers to rapidly cut and mix hydrogen and air, thereby enhancing mixing. However, the complex flow channel design and high blockage of these geometrical flow-disrupting structures result in high flow resistance, leading to significant flow losses.

[0032] Furthermore, due to the extremely high flame propagation speed of hydrogen, a very high mainstream velocity must typically be maintained within the mixing channel to prevent the risk of backfire. Experiments show that a high mainstream velocity of 80 m / s to 120 m / s is usually required within the mixing channel. While this "high flow rate throughout" design logic can establish a backfire prevention barrier, it also leads to a significant total pressure loss as the airflow passes through the microtube premixed burner, resulting in an excessively high overall total pressure loss for the system.

[0033] The high total pressure loss at the mixing end of the premixed combustion unit, combined with the high total pressure loss caused by the high speed required at the backfire prevention end, results in an excessively high overall pressure loss for the microtube premixed burner, making it difficult to meet the stringent requirements of gas turbines for limiting total pressure loss.

[0034] Understandably, a strake wing is an aerodynamic layout structure applied to aircraft. At the leading edge of the strake wing, the airflow undergoes forced three-dimensional flow separation. Under the action of pressure difference, these airflows that have detached from the wing surface are drawn in from bottom to top, forming a highly concentrated and intense spiral vortex, namely the "strake vortex".

[0035] Based on this, the present invention provides a microtube premixed burner. By incorporating a slat-wing vortex generator within the air channel, the vortex generator, with its slat-wing configuration, induces large-scale "slat-wing vortices" within the air channel. These vortices are stable and can generate strong vortices with relatively low pressure heads. Combined with the reduction in the flow area within the mixing channel to increase the mainstream velocity, this achieves short-distance, thorough mixing of hydrogen and air in a low-velocity flow field while ensuring low flow losses and backfire prevention performance. This overcomes the shortcomings of related technologies where hydrogen and air are difficult to mix. While ensuring uniform hydrogen-air mixing, it suppresses and eliminates the formation of localized high-temperature hotspots in the combustion zone, reduces the volume of the high-temperature zone, and significantly limits the generation of nitrogen oxides during combustion, achieving ultra-low emission hydrogen premixed combustion. Simultaneously, it avoids the high pressure loss caused by long-distance, high-speed mainstream flow and provides a high-velocity backfire prevention barrier at the premixing nozzle, thus combining backfire prevention and low-pressure-loss premixing tube design into one, while also considering the safe operation and energy consumption of the microtube premixed burner.

[0036] The following is combined with Figures 1 to 8 The present invention describes a microtube premixed burner based on a wing-shaped vortex generator.

[0037] like Figure 1 As shown, this embodiment provides a microtube premixed combustor 1 based on a strake wing vortex generator. The microtube premixed combustor 1 includes a tube body 10, a fuel tube 20, and a vortex generator 30. The tube body 10 is provided with an air passage 12 and a mixing passage 14. The mixing passage 14 includes a main flow section 141 and a branch flow section 142. The main flow section 141 is connected to the air passage 12, and the branch flow section 142 is located on the side of the main flow section 141 away from the air passage 12 and is connected to the main flow section 141. The flow cross-sectional area of ​​the branch flow section 142 is smaller than that of the main flow section 141. One end of the fuel tube 20 extends into the air passage 12 and is connected to the tube body 10. The fuel tube 20 is provided with a fuel passage 22, which is connected to the air passage 12. The vortex generator 30 is located in the air passage 12 and is connected to the fuel tube 20. The vortex generator 30 is a strake wing vortex generator.

[0038] In this embodiment, the microtube premixed combustor 1 based on a slat vortex generator has air entering the air channel 12. When air passes through the slat vortex generator, a "slat vortex" is generated due to the pressure difference between the upper and lower surfaces of the slat vortex generator. Hydrogen enters the air channel 12 through the fuel channel 22 and mixes with the air that forms the "slat vortex," achieving enhanced mixing. The mixed gas then sequentially enters the main flow section 141 and the branch flow section 142 for further development and mixing, and finally exits through the outlet 145 of the branch flow section 142.

[0039] Because the flow cross-sectional area of ​​the branch section 142 is smaller than that of the main flow section 141 (meaning the main flow section 141 has a larger flow cross-sectional area than the branch section 142), the mixing channel 14 is divided into two parts. A large-diameter channel is used in the main flow section 141 to reduce the main flow velocity, thereby significantly reducing the total pressure loss of the airflow through the mixing channel 14. In the downstream branch section 142, the reduced flow area significantly increases the main flow velocity, thus establishing a backfire barrier in the branch section 142 through a high outlet velocity 145 and a small pipe diameter.

[0040] By incorporating a slat-wing vortex generator within the air channel 12, a large-scale "slat-wing vortex" is induced within the air channel 12 using the slat-wing configuration vortex generator 30. This vortex is stable and can generate a strong vortex with a relatively low pressure head. Combined with the reduction in the flow area within the mixing channel 14 to increase the mainstream velocity, this achieves short-distance, thorough mixing of hydrogen and air in a low-speed flow field while ensuring low flow loss and backfire prevention performance. This overcomes the shortcomings of related technologies where hydrogen and air are difficult to mix. While ensuring uniform hydrogen-air mixing, it suppresses and eliminates the formation of localized high-temperature hotspots in the combustion zone, reduces the volume of the high-temperature zone, and significantly limits the generation of nitrogen oxides during combustion, achieving ultra-low emission hydrogen premixed combustion. Simultaneously, it avoids the high pressure loss caused by long-distance, high-speed mainstream flow and provides a high-velocity backfire prevention barrier at the premixing nozzle, thus combining backfire prevention and low-pressure-loss premixing tube design into one, while also considering the safe operation and energy consumption of the microtube premixed burner 1.

[0041] In some embodiments, such as Figure 1 As shown, the diversion section 142 includes a first section 143 and a second section 144 connected together. The first section 143 is farther away from the main flow section 141 than the second section 144. The side of the first section 143 facing away from the second section 144 has an outlet 145. The flow cross-sectional area of ​​the first section 143 gradually decreases along the direction close to the outlet 145.

[0042] In other words, the section of the diversion section 142 near the outlet 145 adopts a tapering design, which can further increase the airflow velocity at the outlet 145, play a role in preventing backfire, and further ensure backfire safety.

[0043] In some embodiments, such as Figure 1 As shown, the angle between the extensions of the inner walls of the first segment 143 and the inner walls of the second segment 144 is α, where 1°≤α≤10°.

[0044] In this embodiment, the range of the outlet angle 145° is defined. It is understood that if the outlet angle 145° is too small, i.e., less than 1°, the narrowing design of the flow divider section 142 near the outlet 145° will be insignificant and will not effectively prevent backfire. If the outlet angle 145° is too large, i.e., greater than 10°, the opening area of ​​the outlet 145 will be too small, increasing airflow resistance.

[0045] By limiting the outlet 145° angle to between 1° and 10°, a high flow velocity of the mixed airflow at the outlet 145° position can be achieved, thereby preventing backfire.

[0046] In some embodiments, such as Figure 2 As shown, the length of the main flow section 141 in the axial direction of the pipe body 10 is L1, where 15mm≤L1≤80mm; and / or the length of the branch flow section 142 in the axial direction of the pipe body 10 is L2, where 15mm≤L2≤60mm; and / or the number of branch flow sections 142 is n1, where 1≤n1≤12.

[0047] In this embodiment, it is understood that if at least one of the axial length of the main flow section 141 and the axial length of the branch flow section 142 is too short, the overall length of the mixing channel 14 will be too short, and the mixed gas will not be sufficiently developed and integrated within the mixing channel 14, resulting in poor mixing of hydrogen and air. Furthermore, if the axial length of the branch flow section 142 is too short, the velocity distribution of the airflow as it flows through the branch flow section 142 will be poor, posing a risk of backfire. If at least one of the axial lengths of the main flow section 141 and the axial length of the branch flow section 142 is too long, the overall volume of the microtube premixed burner 1 will be too large, affecting assembly.

[0048] By limiting the axial length of the main flow section 141 and the axial length of the branch flow section 142, it is possible to ensure that hydrogen and air are fully developed and integrated in the mixing channel 14 to achieve high-quality mixing. At the same time, the risk of backfire is reduced, and the excessive volume of the microtube premixed burner 1 is avoided from affecting the assembly.

[0049] The number of diversion sections 142 can be set according to actual needs. It can be understood that when there are multiple diversion sections 142, that is, multiple diversion sections 142 array layout. Among them, the flow cross-sectional area of ​​each diversion section 142 is smaller than the flow cross-sectional area of ​​the main flow section 141.

[0050] In some embodiments, such as Figure 2As shown, the pipe body 10 includes a pipe body 16 and a flow guide plate 18. The pipe body 16 is provided with an air passage 12 and a mixing passage 14. The flow guide plate 18 is disposed inside the pipe body 16 and located between the air passage 12 and the mixing passage 14. The flow guide plate 18 extends along the axial direction of the pipe body 10, with one end connected to the inner wall of the pipe body 16 and the other end connected to the outer wall of the fuel pipe 20. The outer wall of the fuel pipe 20, the inner wall of the pipe body 16, and the flow guide plate 18 enclose a vortex chamber 40, through which the air passage 12 communicates with the main flow section 141. A vortex generator 30 is disposed opposite to the vortex chamber 40 along the axial direction of the pipe body 10.

[0051] In other words, the guide plate 18 is located on the low-pressure side of the vortex generator 30. It is understandable that when air flows through the vortex generator 30 with the leading edge wing configuration, a "leading edge vortex" is usually formed on the low-pressure side of the vortex generator 30. The vortex chamber 40 can protect the formed "leading edge vortex", allowing the "leading edge vortex" to develop independently and mix fully with hydrogen, thereby achieving enhanced mixing.

[0052] In addition, since the two ends of the flow guide plate 18 are connected to the outer wall of the fuel pipe 20 and the inner wall of the pipe body 16 respectively, it can also play a role in fixing and supporting the fuel pipe 20.

[0053] In some embodiments, as shown in the figure, there are multiple guide vanes 18, which are arranged circumferentially along the pipe body 10. Any two adjacent guide vanes 18, the outer wall of the fuel pipe 20, and the inner wall of the pipe body 16 enclose a vortex chamber 40. There are also multiple vortex generators 30, which are arranged opposite to the multiple vortex chambers 40 along the axial direction of the pipe body 10.

[0054] In this embodiment, the presence of multiple guide plates 18 enhances the fixation and support effect on the fuel pipe 20. Furthermore, any two adjacent guide plates 18, the outer wall of the fuel pipe 20, and the inner wall of the pipe body 16 enclose a vortex chamber 40. In other words, multiple guide plates 18, the outer wall of the fuel pipe 20, and the inner wall of the pipe body 16 can form multiple vortex chambers 40, which respectively accommodate multiple "strip vortices" generated by multiple leading-edge vortex generators. The guide plates 18 also protect the multiple "strip vortices" from interfering with each other, allowing them to develop and mix independently, thus achieving enhanced mixing.

[0055] In some embodiments, such as Figure 3 and Figure 4As shown, the distance between the end of the flow guide plate 18 near the vortex generator 30 and the end of the vortex generator 30 near the flow guide plate 18 in the axial direction of the pipe body 10 is h, where 1mm≤h≤5mm; and / or the length of the flow guide plate 18 in the axial direction of the pipe body 10 is L3, where 5mm≤L3≤30mm; and / or the number of flow guide plates 18 is n2, where 2≤n2≤8; and / or the thickness of the flow guide plate 18 is t1, where 0.5mm≤t1≤3mm.

[0056] In this embodiment, it is understood that if h is too large, i.e., greater than 5 mm, meaning the distance between the end of the guide plate 18 near the vortex generator 30 and the trailing edge 38 of the vortex generator 30 in the axial direction of the tube body 10 is too far, the multiple "side strip vortices" formed will not be effectively separated by the guide plate 18, causing the multiple "side strip vortices" to affect each other. If h is too small, i.e., less than 1 mm, meaning the distance between the end of the guide plate 18 near the vortex generator 30 and the trailing edge 38 of the vortex generator 30 in the axial direction of the tube body 10 is too close, it will affect the effective formation of the "side strip vortices".

[0057] By limiting h to between 1 mm and 5 mm, it is possible to avoid the mutual influence of multiple "side strip vortices" and allow multiple "side strip vortices" to develop and mix independently, while ensuring the effective formation of "side strip vortices".

[0058] Furthermore, it is understandable that the outer wall of the guide plate 18 constitutes part of the inner wall of the vortex chamber 40. If the length of the guide plate 18 is too short, i.e., less than 5 mm, the "side strip vortex" will have a shorter development time within the vortex chamber 40, affecting the mixing effect with hydrogen. If the length of the guide plate 18 is too long, i.e., greater than 30 mm, the overall size of the microtube premixed burner 1 will be too large, affecting assembly.

[0059] By limiting the length range of the flow guide plate 18, the mixing effect of air and hydrogen can be improved while ensuring the overall size of the microtube premixed burner 1.

[0060] In some embodiments, such as Figure 5 and Figure 6 As shown, the flow guide plate 18 includes a first support plate 19, which forms a cross section along the axial direction perpendicular to the tube body 10 to obtain a first cross section. In this first cross section, the line connecting the trailing edge 38 of the vortex generator 30 away from the center O of the fuel tube 20 to the center O of the fuel tube 20 is a first line 70. The angle between the first line 70 and the center line Q of the first support plate 19 is γ, where 15°≤γ≤75°; and / or, in this first cross section, the angle between the center line P of the split section 142 passing through the center O of the fuel tube 20 and the center line Q of the first support plate 19 is θ, where 45°≤θ≤135°.

[0061] In this embodiment, by limiting the angle between the first line 70 on the first cross section and the center line Q of the first support plate 19 to between 15° and 75°, it is ensured that the axial projection of the vortex generator 30 can be located between two adjacent guide support plates 18, that is, the positional relationship between the vortex generator 30 and the guide support plate 18 is defined, ensuring that the axial projection of the vortex generator 30 is opposite to the vortex chamber 40, thereby ensuring that the "side strip vortex" formed by the air flowing through the vortex generator 30 can develop independently within the vortex chamber 40, which is beneficial to achieving high-quality mixing between air and hydrogen.

[0062] By limiting the angle between the centerline P of the first cross-section of the split section 142 through the centerline O of the fuel pipe 20 and the centerline Q of the first support plate 19 to between 45° and 135°, it is ensured that the "side strip vortex" formed by the airflow through the vortex generator 30 can match the split section 142.

[0063] In some embodiments, such as Figure 7 As shown, the microtube premixed burner 1 also includes a discharge channel 50 and a nozzle 60. A portion of the discharge channel 50 is located in the fuel pipe 20 and communicates with the fuel channel 22, while the other portion is located in the vortex generator 30. The nozzle 60 is located in the vortex generator 30, with one end communicating with the discharge channel 50 and the other end penetrating one side of the vortex generator 30 away from the mixing channel 14.

[0064] In this embodiment, the microtube premixed burner 1 is further defined as including a discharge channel 50 and a nozzle 60. One end of the discharge channel 50 is connected to the fuel channel 22, and the other end is connected to the nozzle 60. That is, hydrogen enters the discharge channel 50 from the fuel channel 22 and is finally ejected through the nozzle 60 to form a hydrogen jet, which mixes with the "side strip vortex" formed in the air channel 12 to achieve enhanced mixing.

[0065] Since the nozzle 60 is located on the side of the vortex generator 30 away from the mixing channel 14, that is, the nozzle 60 is located on the high-pressure side of the vortex generator 30. It can be understood that the "side vortex" is formed on the low-pressure side of the vortex generator 30. By setting the nozzle 60 on the high-pressure side of the vortex generator 30, the hydrogen gas ejected from the nozzle 60 flows along the periphery of the "side vortex" and mixes with the air as much as possible, ensuring sufficient mixing.

[0066] Optionally, both the nozzle 60 and the discharge channel 50 can be located on the fuel pipe 20.

[0067] In some embodiments, the number of nozzles 60 is n3, where 1≤n3≤4; and / or the diameter of the nozzles 60 is d, where 0.4mm≤d≤1.5mm; and / or the distance between the central axis of the nozzles 60 and the trailing edge 38 of the eddy current generator 30 is h2, where 0.5mm≤h2≤3mm.

[0068] In this embodiment, the number of nozzles 60 can be set according to actual needs, for example, 1, 2, 3 or 4.

[0069] Understandably, if the orifice diameter of nozzle 60 is too large, i.e., greater than 1.5 mm, the impact force of hydrogen gas ejected from nozzle 60 will be small, making it impossible to form an effective hydrogen jet. If the orifice diameter of nozzle 60 is too small, i.e. less than 0.4 mm, the resistance of hydrogen gas at nozzle 60 will be large, which will also affect the mixing effect.

[0070] By limiting the orifice diameter of the nozzle 60 to between 0.4 mm and 1.5 mm, it is possible to ensure that the hydrogen jet ejected from the nozzle 60 is effectively mixed with the air.

[0071] Since the distance between the central axis of the nozzle 60 and the trailing edge 38 of the vortex generator 30 is between 0.5 mm and 3 mm, the nozzle 60 is positioned close to the trailing edge 38 of the vortex generator 30. It is understandable that "side vortices" typically form near the leading edge. By positioning the nozzle 60 close to the trailing edge 38 of the vortex generator 30, the hydrogen gas ejected from the nozzle 60 can be moved away from the "side vortex" and flow along the periphery of the "side vortex" to mix with the air, ensuring a good mixing effect.

[0072] In some embodiments, such as Figure 7 As shown, the discharge channel 50 includes a spray section 52, which is located within the vortex generator 30. A second cross-section is obtained by dividing the vortex generator 30 along its thickness direction. In this second cross-section, the central axis E of the nozzle 60 is perpendicular to the centerline F of the spray section 52; and / or, in this second cross-section, the width of the spray section 52 is a1, where 0.6 mm ≤ a1 ≤ 1.2 mm.

[0073] In this embodiment, since the central axis E of the nozzle 60 is perpendicular to the center line F of the ejection section 52 on the second cross section, the hydrogen gas ejected from the nozzle 60 can be far away from the "side strip vortex", allowing the hydrogen jet to flow along the periphery of the "side strip vortex" and mix with the air, which is beneficial to achieving high-quality mixing between hydrogen and air.

[0074] Understandably, if the width of the ejection section 52 is too large, i.e., greater than 1.2 mm, the wall thickness of the vortex generator 30 at the ejection section 52 will be too small. During the mixing of hydrogen and air, it will be prone to deformation or breakage, and will affect the smooth formation of the "side filament vortex". If the width of the ejection section 52 is too small, i.e., less than 0.6 mm, that is, the flow cross-sectional area of ​​the ejection section 52 is too small, the flow velocity and resistance of hydrogen when flowing through the ejection section 52 will be large.

[0075] By limiting the width of the ejection section 52 to between 0.6 mm and 1.2 mm, the structural stability of the vortex generator 30 is ensured while avoiding excessive flow velocity and resistance of hydrogen gas when it flows through the ejection section 52.

[0076] In some embodiments, such as Figure 8 As shown, the vortex generator 30 includes a straight section 32 and a vortex section 34, with the vortex section 34 connected to the straight section 32. The nozzle 60 is located in the straight section 32.

[0077] In this embodiment, the specific structure of the eddy current generator 30 is defined, wherein the eddy current can be maintained by providing a straight section 32.

[0078] Understandably, the "strip vortex" formed after the air flows through the strip vortex generator is usually close to the vortex section 34. By setting the nozzle 60 in the straight section 32, that is, by moving the nozzle 60 relatively away from the "strip vortex", the ejected hydrogen can flow along the periphery of the "strip vortex" and mix with the air, ensuring full mixing.

[0079] In some embodiments, such as Figure 8 As shown, the length of the straight section 32 is L4, where 0mm < L4 ≤ 8mm; and / or the width of the straight section 32 is a2, where 2mm ≤ a2 ≤ 12mm; and / or the eddy current generator 30 includes a connecting end 36, which is connected to the fuel pipe 20, and the length of the connecting end 36 is L5, where 10mm ≤ L5 ≤ 30mm.

[0080] In this embodiment, by defining the length and width range of the straight section 32 and the length range of the connecting end 36, the intensity, size, and location of the "strip vortex" generated when air flows through the strip vortex generator can be defined, ensuring effective mixing of hydrogen and air. Specific parameters can be set according to actual needs.

[0081] In some embodiments, such as Figure 2 and Figure 7As shown, the thickness of the eddy current generator 30 is t2, where 0.8mm≤t2≤3.2mm; and / or the number of eddy current generators 30 is n4, where 1≤n4≤8; and / or a second cross-section is obtained by dividing the eddy current generator 30 along its thickness direction, where the angle between the centerline of the eddy current generator 30 and the horizontal plane is β, where 5°≤β≤30°; and / or the outer diameter of the tube body 16 is D1, where 10mm≤D1≤40mm; and / or the wall thickness of the tube body 16 is t3, where 0.5mm≤t3≤5mm; and / or the length of the tube body 16 is L, where 60mm≤L≤200mm; and / or the outer diameter of the fuel pipe 20 is D2, where 4mm≤D2≤20mm; and / or the wall thickness of the fuel pipe 20 is t4, where 0.5mm≤t4≤3mm.

[0082] In this embodiment, since the angle between the centerline of the eddy current generator 30 and the horizontal plane on the second cross section is between 5° and 30°, the angle of attack range of the eddy current generator 30 is limited to 5°~30°. If the angle is too large, the formed "side strip vortex" may break prematurely, affecting the mixing effect. If the angle is too small, the strength of the formed "side strip vortex" will be insufficient, which will also affect the mixing effect.

[0083] By limiting the angle of attack of the vortex generator 30 to between 5° and 30°, the strength of the formed "side strip vortex" can be ensured, further enabling high-quality mixing between hydrogen and air.

[0084] Furthermore, the thickness and number of eddy current generators 30 can be set according to actual needs.

[0085] Understandably, if the outer diameter of the tube 10 remains unchanged, but the outer diameter of the fuel tube 20 is too large, the effective cross-sectional area of ​​the mixing region of air and hydrogen in the air channel 12 will be too small, resulting in increased airflow velocity and greater losses. If the outer diameter of the tube 10 remains unchanged, but the outer diameter of the fuel tube 20 is too small, with the size of the vortex generator 30 remaining unchanged, some air will not flow through the vortex generator 30 and will directly enter the mixing channel 14, affecting the mixing effect.

[0086] By limiting the outer diameter and wall thickness of the tube 10 and the outer diameter and wall thickness of the fuel tube 20, the effective cross-sectional area of ​​the mixing region of air and hydrogen in the air channel 12 can be limited, achieving high-quality mixing of air and hydrogen while ensuring low flow loss.

[0087] If the length of the tube 10 is too short, i.e. less than 60 mm, the lengths of the air channel 12 and the mixing channel 14 inside the tube 10 will be too short, affecting the mixing effect of hydrogen and air. If the length of the tube 10 is too long, i.e. greater than 200 mm, the overall size of the microtube premixed burner 1 will be too large, affecting assembly.

[0088] By limiting the length of the tube 10 to between 60mm and 200mm, it is possible to achieve full mixing of hydrogen and air while ensuring the overall size of the microtube premixed burner 1, thereby reducing the volume of the high-temperature zone and reducing nitrogen oxide emissions.

[0089] In one specific embodiment, the existing structure of hydrogen premixed microtube combustion in related technologies struggles to simultaneously meet the three major requirements of "efficient mixing, stable backfire prevention, and low pressure loss operation." Furthermore, it often sacrifices total pressure loss for backfire prevention, or requires sacrificing mixing uniformity for emissions in exchange for safe combustion performance. This severely restricts the engineering practicality of high-performance hydrogen fuel combustion chambers.

[0090] This invention provides a hydrogen premixed microtube bundle burner (microtube premixed burner 1) that can take into account backfire prevention, low total pressure loss and low nitrogen oxide emissions. It includes an air inlet channel (air channel 12), a fuel inlet channel (fuel channel 22), a slat wing configuration vortex generator (vortex generator 30), a hydrogen channel (discharge channel 50), a hydrogen nozzle (nozzle 60), a guide plate 18, a main flow mixing channel (main flow section 141), a microtube bundle branch pipe (branching section 142), and a microtube outlet (outlet 145).

[0091] The air inlet channel is formed by the inner wall of the premixing tube (tube body 10) and the outer wall of the fuel channel (fuel tube 20), and is fixed by the guide plate 18. When air passes through the strake wing configuration vortex generator, a "strake vortex" is generated due to the pressure difference between the upper and lower surfaces. Hydrogen enters the premixing tube through the fuel inlet channel, passes through the hydrogen channel, and is ejected through the hydrogen nozzle, forming a hydrogen jet that mixes with the mainstream air. The hydrogen nozzle is located on the high-pressure side (lower surface) of the strake wing configuration vortex generator. After being ejected, the hydrogen flows along the periphery of the "strake vortex" and mixes with the mainstream air.

[0092] There are several leading-edge wing configuration vortex generators, which will produce the same number of small "leading-edge vortices". The number of guide plates 18 is the same as that of the leading-edge wing configuration vortex generator. In addition to the fixing function, the area (vortex chamber 40) enclosed by the guide plates 18, the inner wall of the premixing pipe and the outer wall of the fuel passage can protect the small "leading-edge vortices" from affecting each other and allowing them to develop and mix independently, thereby achieving enhanced mixing.

[0093] After the mixed gas travels a certain distance, it merges into the mainstream mixing channel (mainstream section 141). Several small "sidewall vortices" continuously merge, further enhancing the mixing degree. At the same time, the large-diameter mixing channel can maintain a low total pressure loss. The mainstream mixed gas enters the microtube bundle branch pipe (branching section 142). The velocity inside the microtube bundle branch pipe and at the microtube outlet is relatively high. Meanwhile, the microtube outlet adopts a tapering design, which can play a role in preventing backfire.

[0094] Figure 3 This is an axial view of the inlet and outlet of the premixed microtube. (Example:) Figure 3 As shown, the vortex generator, guide vane 18, and microtube bundle branch pipes in the strake configuration each number four. Figure 7 As shown, the vortex generator with a leading-edge extension configuration is a flat airfoil. Figure 8 As shown, the vortex generator with a leading-edge extension configuration has an arched leading-edge extension, and also includes a straight section 32 to maintain the vortex. The hydrogen nozzles can be arranged at any position in the microtube premixed burner 1.

[0095] This invention provides a hydrogen premixed microtube bundle (microtube premixed burner 1) based on a strake-wing configuration vortex generator, overcoming the inherent defects of existing hydrogen micro premixed burners that struggle to simultaneously achieve hydrogen / air mixing, backfire prevention, and low total pressure loss. This invention employs a large-diameter channel in the mixing section to create a low-speed mixing environment and reduce total pressure loss. In the outlet section, it transitions to a high-velocity microtube bundle layout to establish a backfire prevention barrier. Furthermore, it innovatively introduces a strake-wing aerodynamic configuration into the premixed microtube as a vortex generator 30, achieving thorough hydrogen / air mixing while ensuring low flow loss.

[0096] Compared to existing technologies, this invention ensures uniform mixing of hydrogen and air while maintaining the backfire safety and low total pressure loss of the microtube device. This achieves the goal of safely and stably suppressing the formation of localized high-temperature hotspots in the downstream combustion zone, thereby significantly limiting the generation of nitrogen oxides during combustion. This invention enables efficient, stable, and ultra-low emission hydrogen premixed combustion while maintaining extremely low total pressure loss, providing a new premixed combustion solution for the development of high-efficiency, zero-carbon emission next-generation aero-engines.

[0097] Among them, the microtube premixed burner 1 can be applied to the combustion chamber of a gas turbine engine to meet its requirements for low nitrogen oxide emissions, low total pressure loss and backfire prevention safety.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A microtube premixed burner based on a winglet vortex generator, characterized in that, include: The pipe body is provided with an air passage and a mixing passage. The mixing passage includes a main flow section and a branch flow section. The main flow section is connected to the air passage. The branch flow section is located on the side of the main flow section away from the air passage and is connected to the main flow section. The flow cross-sectional area of ​​the branch flow section is smaller than that of the main flow section. A fuel pipe, one end of which extends into the air passage and is connected to the pipe body; the fuel pipe is provided with a fuel passage that communicates with the air passage. A vortex generator is located inside the air passage and connected to the fuel pipe; The vortex generator is a strake wing vortex generator.

2. The microtube premixed burner based on a winglet vortex generator according to claim 1, characterized in that, The diversion section includes a first section and a second section connected together. The first section is farther away from the main flow section than the second section, and the side of the first section opposite to the second section has an outlet. In particular, along the direction closer to the outlet, the flow cross-sectional area of ​​the first segment gradually decreases.

3. The microtube premixed burner based on a winglet vortex generator according to claim 2, characterized in that, The angle between the extensions of the inner walls of the first segment and the inner walls of the second segment is α, where 1°≤α≤10°.

4. The microtube premixed burner based on a winglet vortex generator according to claim 1, characterized in that, The length of the main stream section along the axial direction of the pipe body is L1, wherein 15mm ≤ L1 ≤ 80mm; and / or The length of the diversion section along the axial direction of the pipe body is L2, wherein 15mm ≤ L2 ≤ 60mm; and / or The number of diversion sections is n1, where 1≤n1≤12.

5. The microtube premixed combustor based on a winglet vortex generator according to any one of claims 1 to 4, characterized in that, The tube body includes: The pipe body is provided with the air passage and the mixing passage; A flow guide plate is disposed within the pipe body and located between the air passage and the mixing passage. The flow guide plate extends axially along the pipe body. One end of the flow guide plate is connected to the inner wall of the pipe body, and the other end is connected to the outer wall of the fuel pipe. The outer wall of the fuel pipe, the inner wall of the pipe body, and the flow guide plate enclose a vortex chamber. The air passage communicates with the main flow section through the vortex chamber. Along the axial direction of the tube, the vortex generator is positioned opposite to the vortex chamber.

6. The microtube premixed burner based on a winglet vortex generator according to claim 5, characterized in that, The number of the flow guide plates is multiple, and the multiple flow guide plates are arranged along the circumference of the pipe body. Any two adjacent flow guide plates, the outer wall of the fuel pipe and the inner wall of the pipe body enclose a vortex chamber. The tube body contains multiple vortex generators, which are arranged opposite to multiple vortex chambers along the axial direction of the tube.

7. The microtube premixed burner based on a winglet vortex generator according to claim 5, characterized in that, The distance between the end of the guide plate near the vortex generator and the end of the vortex generator near the guide plate in the axial direction of the pipe body is h1, where 1mm ≤ h1 ≤ 5mm; and / or The length of the guide plate in the axial direction of the pipe body is L3, wherein 5mm ≤ L3 ≤ 30mm; and / or The number of the flow guide plates is n2, where 2 ≤ n2 ≤ 8; and / or The thickness of the flow guide plate is t1, wherein 0.5mm ≤ t1 ≤ 3mm; and / or The outer diameter of the tube body is D1, wherein 10mm ≤ D1 ≤ 40mm; and / or The wall thickness of the pipe body is t3, wherein 0.5mm ≤ t3 ≤ 5mm; and / or The length of the tube body is L, where 60mm≤L≤200mm.

8. The microtube premixed burner based on a winglet vortex generator according to claim 5, characterized in that, The flow guide plate includes a first support plate, which forms a cross section of the microtube premixed burner along an axial direction perpendicular to the tube body to obtain a first cross section; Wherein, on the first cross section, the line connecting the rear edge of the eddy current generator away from the center of the fuel pipe and the center of the fuel pipe is the first line, and the angle between the first line and the center line of the first support plate is γ, wherein 15°≤γ≤75°; and / or, on the first cross section, the angle between the center line of the split section passing through the center of the fuel pipe and the center line of the first support plate is θ, wherein 45°≤θ≤135°.

9. The microtube premixed combustor based on a winglet vortex generator according to any one of claims 1 to 4, characterized in that, The microtube premixed burner also includes: The discharge channel, a part of which is located in the fuel pipe and communicates with the fuel channel, and the other part of which is located in the eddy current generator; A nozzle is provided in the vortex generator, one end of which is connected to the discharge channel, and the other end of which passes through one side of the vortex generator away from the mixing channel.

10. The microtube premixed burner based on a winglet vortex generator according to claim 9, characterized in that, The number of nozzles is n3, where 1 ≤ n3 ≤ 4; and / or The diameter of the nozzle is d, where 0.4 mm ≤ d ≤ 1.5 mm; and / or The distance between the central axis of the nozzle and the trailing edge of the vortex generator is h2, where 0.5mm≤h2≤3mm.

11. The microtube premixed burner based on a winglet vortex generator according to claim 9, characterized in that, The discharge channel includes a spray section, which is located in the vortex generator; a second cross-section is obtained by cutting the vortex generator along its thickness direction; Wherein, on the second cross section, the central axis of the nozzle is perpendicular to the center line of the ejection section; and / or, on the second cross section, the width of the ejection section is a1, wherein 0.6mm≤a1≤1.2mm.

12. The microtube premixed burner based on a winglet vortex generator according to claim 9, characterized in that, The eddy current generator includes: Straight section; The vortex section is connected to the straight section; The nozzle is located in the straight section.

13. The microtube premixed burner based on a winglet vortex generator according to claim 12, characterized in that, The length of the straight section is L4, where 0mm < L4 ≤ 8mm; and / or The width of the straight section is a2, where 2mm ≤ a2 ≤ 12mm; and / or The eddy current generator includes a connecting end, which is connected to the fuel pipe. The length of the connecting end is L5, wherein 10mm≤L5≤30mm.

14. The microtube premixed combustor based on a winglet vortex generator according to any one of claims 1 to 4, characterized in that, The thickness of the eddy current generator is t2, where 0.8 mm ≤ t2 ≤ 3.2 mm; and / or The number of eddy current generators is n4, where 1 ≤ n4 ≤ 8; and / or A second cross-section is obtained by cutting the eddy current generator along its thickness direction. On this second cross-section, the angle between the centerline of the eddy current generator and the horizontal plane is β, where 5° ≤ β ≤ 30°; and / or The outer diameter of the fuel pipe is D2, wherein 4mm ≤ D2 ≤ 20mm; and / or The wall thickness of the fuel pipe is t4, where 0.5mm ≤ t4 ≤ 3mm.

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