Triangular section flute-shaped pipe hydrogen combustion system, mixing assembly and method

Abstract

The invention belongs to the technical field of hydrogen mixing, and provides a triangular-section flute-shaped pipe hydrogen mixing assembly, a combustion system and a method. A hydrogen conveying pipe penetrates through an insertion hole and extends into a natural gas conveying pipe; a hydrogen outlet is formed in the part, located in the natural gas conveying pipe, of the hydrogen conveying pipe; the hydrogen conveying pipe is a triangular pipeline, one corner of the hydrogen conveying pipe faces a natural gas inlet of the natural gas conveying pipe, a hydrogen outlet is formed in the side face, away from the natural gas inlet, of the hydrogen conveying pipe, and vortex street turbulent flow can be generated at the triangular pipeline so that mixing of natural gas and hydrogen can be enhanced; natural gas turbulent flow can generate negative pressure on the face where the flute-shaped holes are located, introduction of hydrogen with the pressure lower than that of natural gas is achieved, in addition, due to the triangular design, vortex with higher frequency can be generated on the rear portion, stronger turbulent flow has the efficient mixing effect, mixing can be even, the distance can be shortened, and the pipeline and installation space is saved.

Description

Technical Field

[0001] This invention belongs to the field of combustion technology, and particularly relates to a triangular cross-section flute tube hydrogen combustion system, mixing components and methods. Background Technology

[0002] With the vigorous promotion and demand for emission reduction worldwide, efficient and clean energy is being widely used. Hydrogen energy, due to its easy combustion and pollution-free combustion products, is currently considered one of the most promising energy sources for development. Blending hydrogen with natural gas for combustion is one of the best transitional solutions for promoting the decarbonization of the energy structure.

[0003] Hydrogen and natural gas need to be mixed before they can be used together. However, the density of hydrogen is much lower than that of natural gas, making it difficult to mix them evenly. The pipe sections required for even mixing are long, which can lead to hydrogen embrittlement of metal materials and other safety issues. At the same time, because hydrogen and natural gas cannot be fully mixed, it will result in low combustion efficiency and incomplete combustion. In addition, excessive hydrogen in some areas may also cause deflagration. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a triangular cross-section flute-shaped tube hydrogen mixing assembly, combustion system, and method. The triangular tube generates vortex shear, enhancing the mixing of natural gas and hydrogen. Simultaneously, the natural gas shear generates negative pressure on the surface directly opposite the natural gas flow (the surface where the flute-shaped orifice is located), enabling the introduction of hydrogen at a pressure lower than that of natural gas. This solves the problem of difficulty in achieving uniform mixing due to the extremely low density of hydrogen and the density of natural gas. Furthermore, compared to traditional circular tubes as hydrogen inlet pipes, the triangular design generates higher-frequency vortices and stronger turbulence at its rear, resulting in highly efficient mixing. This also shortens the uniform mixing distance, saving pipeline and installation space.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a triangular cross-section flute-shaped tube hydrogen mixing assembly, employing the following technical solution:

[0006] A triangular cross-section flute-shaped tube hydrogen blending assembly includes a natural gas transmission pipe and a hydrogen transmission pipe;

[0007] The natural gas pipeline has an insertion hole, and the hydrogen pipeline extends through the insertion hole into the natural gas pipeline; the portion of the hydrogen pipeline located inside the natural gas pipeline has a hydrogen outlet; the hydrogen pipeline has a triangular cross-section in the vertical length direction, with one corner of the hydrogen pipeline facing the natural gas inlet of the natural gas pipeline, and the hydrogen outlet is located on the side of the hydrogen pipeline facing away from the natural gas inlet.

[0008] Furthermore, multiple hydrogen outlets are provided on the side of the hydrogen delivery pipe opposite to the natural gas delivery pipe; in the vertical direction from top to bottom, the flow area of ​​the hydrogen outlets increases with each other, and the magnitude of the increase continuously increases.

[0009] Furthermore, the hydrogen delivery pipe is inclinedly disposed on the natural gas delivery pipe.

[0010] To achieve the above objectives, in a second aspect, the present invention also provides a triangular cross-section flute-shaped tube hydrogen blending and combustion system, employing the following technical solution:

[0011] A triangular cross-section flute-shaped tube hydrogen blending and combustion system includes a fuel inlet, a combustion section connected to the fuel inlet, and a system outlet connected to the combustion section; a blending assembly is disposed within the fuel inlet; the blending assembly includes a natural gas delivery pipe and a hydrogen delivery pipe;

[0012] The natural gas pipeline has an insertion hole, and the hydrogen pipeline extends through the insertion hole into the natural gas pipeline; the portion of the hydrogen pipeline located inside the natural gas pipeline has a hydrogen outlet; the hydrogen pipeline has a triangular cross-section in the vertical length direction, with one corner of the hydrogen pipeline facing the natural gas inlet of the natural gas pipeline, and the hydrogen outlet is located on the side of the hydrogen pipeline facing away from the natural gas inlet.

[0013] Furthermore, multiple hydrogen outlets are provided on the side of the hydrogen delivery pipe opposite to the natural gas delivery pipe.

[0014] Furthermore, the hydrogen delivery pipe is inclinedly disposed on the natural gas delivery pipe.

[0015] Furthermore, the combustion section is a horizontal section, and an extension section connects the fuel inlet to the combustion section; a recess section connects the combustion section to the system outlet.

[0016] Furthermore, an air supply unit is provided outside the areas where the extension section, the combustion section, and the retraction section are located.

[0017] Furthermore, the air supply unit includes an air duct, and a first air inlet, a second air inlet, and a third air inlet located on the air duct at the positions of the recessed section, the combustion section, and the extended section, respectively; the air inlets on the air duct are close to the system outlet, and the air outlets on the air duct are close to the fuel inlet.

[0018] To achieve the above objectives, in a third aspect, the present invention also provides a method for hydrogen mixing in a triangular cross-section flute-shaped tube, employing the following technical solution:

[0019] A method for hydrogen blending using a triangular cross-section flute tube, employing a triangular cross-section flute tube hydrogen blending assembly as described in the first aspect, includes: generating vortex turbulence at the hydrogen delivery pipe within a natural gas delivery pipe to blend natural gas and hydrogen; simultaneously, the natural gas turbulence generates negative pressure at the surface where the hydrogen outlet is located to introduce hydrogen.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] In this invention, a hydrogen delivery pipe extends through a through-hole into the interior of the natural gas delivery pipe; the portion of the hydrogen delivery pipe inside the natural gas delivery pipe has a hydrogen outlet; the hydrogen delivery pipe is a triangular pipe, with one corner facing the natural gas inlet of the natural gas delivery pipe, and the hydrogen outlet is located on the side of the hydrogen delivery pipe facing away from the natural gas inlet, forming a flute-shaped pipe and a flute-shaped orifice; vortex turbulence can occur at the triangular pipe, thereby enhancing the mixing of natural gas and hydrogen. At the same time, the natural gas turbulence will generate negative pressure on the surface directly opposite the natural gas flow (the surface where the flute-shaped orifice is located), enabling the introduction of hydrogen at a pressure lower than the natural gas pressure. This solves the problem of difficulty in uniform mixing caused by the extremely low density of hydrogen and the density of natural gas. Furthermore, compared to the traditional round pipe as a hydrogen inlet pipe, the triangular design allows for the generation of higher frequency vortices and stronger turbulence at its rear, resulting in a more efficient mixing effect. This can shorten the uniform mixing distance, saving pipeline and installation space.

[0022] In this invention, a blending component is disposed within the fuel inlet. The expansion section, combustion section, and concave section constitute a mixing chamber with an internal spatial cross-section larger than that of the fuel inlet. The hydrogen and natural gas blended by the blending component continue to mix within the mixing chamber, improving the blending effect. After passing through the concave section, the gas enters the system outlet, further achieving the blending objective. Through the coordination of the blending component, expansion section, combustion section, and concave section, the uniformity of hydrogen and natural gas blending throughout the combustion process is ensured, guaranteeing combustion efficiency and complete combustion.

[0023] In this invention, a first air inlet, a second air inlet, and a third air inlet are respectively provided at the positions of the converging section, the combustion section, and the expansion section. The first air inlet, the second air inlet, and the third air inlet respectively realize the functions of dilution, combustion assistance, and vortex mixing. In particular, the third air inlet is located at the position of the expansion section, and in conjunction with the structure of the mixing component and the expansion section, it forms a better vortex in the recirculation zone, which further improves and ensures the mixing effect and uniformity of hydrogen and natural gas. Attached Figure Description

[0024] The accompanying drawings, which form part of this embodiment, are used to provide a further understanding of this embodiment. The illustrative embodiments and their descriptions are used to explain this embodiment and do not constitute an improper limitation of this embodiment.

[0025] Figure 1 This is a schematic diagram of the mixing component structure in Embodiment 1 of the present invention;

[0026] Figure 2 This is a schematic diagram of the natural gas transmission pipeline structure according to Embodiment 1 of the present invention;

[0027] Figure 3 This is a schematic diagram of the hydrogen delivery pipe structure according to Embodiment 1 of the present invention;

[0028] Figure 4 This is a schematic diagram of the hydrogen outlet structure in Embodiment 1 of the present invention;

[0029] Figure 5 This is a schematic diagram of the mixing component structure in Embodiment 2 of the present invention;

[0030] Figure 6 This is a schematic diagram of the inclined state of the hydrogen delivery pipe in Embodiment 2 of the present invention;

[0031] Figure 7 This is a schematic diagram of the combustion system structure of Embodiment 3 of the present invention;

[0032] The components are as follows: 1. Blending assembly; 101. Natural gas transmission pipe; 1011. Natural gas inlet; 1012. Insertion port; 102. Hydrogen transmission pipe; 1021. Hydrogen inlet; 1022. Hydrogen outlet; 2. Combustion system; 201. Fuel inlet; 202. Recirculation zone; 203. System outlet; 204. Air supply unit; 2041. Air inlet; 2042. Air duct; 2043. First air inlet; 2044. Second air inlet; 2045. Third air inlet; 2046. Air outlet; 205. Extension section; 206. Combustion section; 207. Retraction section. Detailed Implementation

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0035] With the global push for emission reduction, efficient and clean energy is being widely adopted. Hydrogen energy, due to its easy combustion and pollution-free combustion products, is considered one of the most promising energy sources for development. Blending hydrogen with natural gas for combustion is currently one of the best transitional solutions for promoting a low-carbon energy structure. However, existing technologies, such as spray technology to ensure uniform heat exchange and improve thermal efficiency, are costly due to their structure. Furthermore, the inability to adjust specific temperature ranges according to actual needs limits their application. Some burners integrating sensors and other precision detection instruments are too expensive to be widely used. Additionally, burner malfunctions and failure to exchange heat with the liquid can easily lead to burns for users. Blending hydrogen and natural gas is necessary for co-utilization, but the low density of hydrogen compared to natural gas makes uniform mixing difficult. The required pipe length for uniform mixing is long, increasing the risk of hydrogen embrittlement of metal materials. Simultaneously, the incomplete mixing of hydrogen and natural gas results in low combustion efficiency and incomplete combustion, and excessive local hydrogen can lead to deflagration.

[0036] To address the problems mentioned above, such as long pipe section distances, low combustion efficiency, and incomplete combustion, such as Figure 1 As shown, this embodiment provides a triangular cross-section flute-shaped tube hydrogen blending assembly 1, including a natural gas transmission pipe 101 and a hydrogen transmission pipe 102.

[0037] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the natural gas transmission pipe 101 has an insertion hole 1012, and the hydrogen transmission pipe 102 extends through the insertion hole 1012 into the natural gas transmission pipe 101; the portion of the hydrogen transmission pipe 102 located inside the natural gas transmission pipe 101 has a hydrogen outlet 1022; the hydrogen transmission pipe 102 has a triangular cross-section in the vertical length direction, with one corner of the hydrogen transmission pipe 102 facing the natural gas inlet 1011 of the natural gas transmission pipe 101, and the hydrogen outlet 1022 is located on the side of the hydrogen transmission pipe 102 facing away from the natural gas inlet 1011.

[0038] Specifically, the hydrogen outlet 1022 is located on the side of the hydrogen delivery pipe 102 opposite to the natural gas inlet 1011, forming a flute-shaped pipe and a flute-shaped orifice. Vortex turbulence can be generated at the triangular pipe, thereby enhancing the mixing of natural gas and hydrogen. At the same time, the natural gas turbulence will generate negative pressure on the surface directly opposite the natural gas flow (the surface where the flute-shaped orifice is located), which can achieve the introduction of hydrogen at a pressure lower than that of natural gas. This solves the problem of difficulty in uniform mixing caused by the extremely low density of hydrogen and the density of natural gas. Furthermore, compared with the traditional round pipe as a hydrogen inlet pipe, the triangular design can generate higher frequency vortices and stronger turbulence at its rear, resulting in a more efficient mixing effect. It can also shorten the uniform mixing distance, saving pipeline and installation space.

[0039] Understandably, the hydrogen inlet 1021 of the hydrogen delivery pipe 102 is located outside the natural gas delivery pipe 101. The natural gas delivery pipe 101 can be a circular pipe, a square pipe, or other types of pipe. The top of the hydrogen delivery pipe 102 located inside the natural gas delivery pipe 101 can be sealed, so that hydrogen is completely discharged into the natural gas delivery pipe 101 through the hydrogen outlet 1022.

[0040] The structure of the socket 1012 is adapted to the structure of the hydrogen delivery pipe 102. The hydrogen delivery pipe 102 is fixed in the socket 1012 by welding or other means, and the connection is sealed.

[0041] In some embodiments, a plurality of hydrogen outlets 1022 are provided on the side of the hydrogen delivery pipe 102 opposite to the natural gas delivery pipe 101; the number of hydrogen outlets 1022 can be multiple; and the hydrogen outlets 1022 can be round holes, square holes or other structural forms of holes.

[0042] As an improvement, the hydrogen delivery pipe 102 is inserted vertically into the natural gas delivery pipe 101, and the flow area of ​​the hydrogen outlet 1022 increases from top to bottom in the vertical direction. Because hydrogen has a lower density than natural gas, it naturally flows upward. By varying the size of the hydrogen outlet 1022 in the vertical direction, more air can enter the lower space, thus ensuring a more uniform distribution of hydrogen throughout the space. This avoids uneven mixing caused by uneven hydrogen distribution, resulting in low combustion efficiency and different ignition points due to uneven local distribution, preventing accidents such as deflagration.

[0043] As an improvement, the flow area of ​​the hydrogen outlet 1022 increases progressively from top to bottom in the vertical direction. This configuration further ensures more uniform hydrogen distribution and improves combustion efficiency.

[0044] As an improvement, the hydrogen delivery pipe 102 is inserted vertically into the natural gas delivery pipe 101 from below. By inserting it from below, the hydrogen distribution at the bottom is maximized, reducing uneven distribution caused by the low density of hydrogen.

[0045] like Figure 5 and Figure 6 As shown, this embodiment provides a triangular cross-section flute-shaped tube hydrogen blending assembly. Unlike the blending assembly 1 in Embodiment 1, in this embodiment, the hydrogen delivery pipe 102 in the blending assembly 1 is inclinedly arranged on the natural gas delivery pipe 101.

[0046] Understandably, the hydrogen delivery pipe 102 is inclined, and the hydrogen is discharged at an inclined direction from the hydrogen outlet 1022 toward the side wall of the natural gas delivery pipe 101. When it mixes with the natural gas flowing in horizontally, compared with the hydrogen being discharged horizontally from the hydrogen outlet 1022, the vortex effect is improved, which can further improve the mixing effect and mixing uniformity with the natural gas.

[0047] As an improvement, such as Figure 5 and Figure 6 As shown, the inclination direction is towards the natural gas flow direction. As an improvement, the inclination angle with the natural gas flow direction decreases along the natural gas flow direction. That is, the hydrogen delivery pipe 102 is not a straight line, but a curved one, with the tangent of the curve forming an inclination angle with the natural gas flow direction. This arrangement makes the hydrogen delivery pipe 102 more horizontal towards the top. This optimized design changes the turbulence of the natural gas, significantly enhances the vortex effect, prolongs and intermittently mixes the time, thereby significantly improving the mixing efficiency of hydrogen and natural gas. Furthermore, because the hydrogen outlet 1022 is perpendicular to the hydrogen delivery pipe 102, the outlet direction of the hydrogen outlet 1022 tilts downwards towards the top, thus reducing the amount of hydrogen flowing upwards due to density issues, greatly improving the overall uniformity of mixing with natural gas.

[0048] As an improvement, a flow guiding device is provided at the hydrogen outlet 1022, which tilts the hydrogen outlet 1022 at a certain angle. Along the vertical direction from bottom to top, the flow guiding device makes the hydrogen outlet 1022 tilt increasingly upwards. This design avoids the problem of low hydrogen density, allowing the inlet hydrogen at the bottom to flow downwards as much as possible, thus overcoming the density issue and greatly improving the overall mixing uniformity with natural gas. Optionally, the flow guiding device can be an independent tubular structure, nozzle, or other outlet structure located at the hydrogen outlet 1022; the flow guiding device can also be integrated with the hydrogen outlet 1022, with the angle set during the processing of the hydrogen outlet 1022.

[0049] This embodiment provides a triangular cross-section flute-shaped tube hydrogen blending combustion system 2, including a fuel inlet 201, a recirculation zone 202, a combustion section 206 communicating with the fuel inlet 201, and a system outlet 203 communicating with the combustion section 206; a blending component 1 is provided in the fuel inlet 201; the blending component 1 includes a natural gas delivery pipe 101 and a hydrogen delivery pipe 102.

[0050] The natural gas transmission pipe 101 has an insertion hole 1012, and the hydrogen transmission pipe 102 extends through the insertion hole 1012 into the natural gas transmission pipe 101; the portion of the hydrogen transmission pipe 102 located inside the natural gas transmission pipe 101 has a hydrogen outlet 1022; the hydrogen transmission pipe 102 has a triangular cross-section in the vertical length direction, with one corner of the hydrogen transmission pipe 102 facing the natural gas inlet 1011 of the natural gas transmission pipe 101, and the hydrogen outlet 1022 is located on the side of the hydrogen transmission pipe 102 facing away from the natural gas inlet 1011.

[0051] Understandably, the hydrogen inlet 1021 of the hydrogen delivery pipe 102 is located outside the natural gas delivery pipe 101. The natural gas delivery pipe 101 can be a circular pipe, a square pipe, or other types of pipe. The top of the hydrogen delivery pipe 102 located inside the natural gas delivery pipe 101 can be sealed, so that hydrogen is completely discharged into the natural gas delivery pipe 101 through the hydrogen outlet 1022.

[0052] The structure of the socket 1012 is adapted to the structure of the hydrogen delivery pipe 102. The hydrogen delivery pipe 102 is fixed in the socket 1012 by welding or other means, and the connection is sealed.

[0053] In some embodiments, a plurality of hydrogen outlets 1022 are provided on the side of the hydrogen delivery pipe 102 opposite to the natural gas delivery pipe 101; the number of hydrogen outlets 1022 can be multiple; and the hydrogen outlets 1022 can be round holes, square holes or other structural forms of holes.

[0054] The combustion section 206 is a horizontal section, and an extension section 205 connects the fuel inlet 201 to the combustion section 206; a recessed section 207 connects the combustion section 206 to the system outlet 203.

[0055] Optionally, the blending component 1 is disposed at one end of the fuel inlet 201 near the extension section 205; the extension section 205, the combustion section 206, and the recessed section 207 constitute a mixing chamber with an internal space cross-section larger than that of the fuel inlet 201; the hydrogen and natural gas blended by the blending component 1 continue to mix in the mixing chamber formed by the extension section 205, the combustion section 206, and the recessed section 207, improving the blending effect, and after passing through the recessed section 207, enters the system outlet 203, further achieving the blending purpose. Through the cooperation of the blending component 1, the extension section 205, the combustion section 206, and the recessed section 207, the uniformity of the blending of hydrogen and natural gas throughout the combustion process is ensured.

[0056] An air supply component 204 is provided outside the area where the extension section 205, the combustion section 206, and the retracted section 207 are located. The air supply component 204 includes an air duct 2042, and a first air inlet 2043, a second air inlet 2044, and a third air inlet 2045 located at the positions of the retracted section 207, the combustion section 206, and the extension section 205, respectively, on the air duct 2042; the air inlet 2041 on the air duct 2042 is close to the system outlet 203, and the air outlet 2046 on the air duct 2042 is close to the fuel inlet 201.

[0057] Understandably, the first air inlet 2043, the second air inlet 2044, and the third air inlet 2045 respectively perform dilution, combustion support, and vortex mixing functions. In particular, the third air inlet 2045 is located at the extension section 205, and in conjunction with the mixing component 1 and the extension section 205, forms a well-functioning vortex in the recirculation zone 202, further improving and ensuring the mixing effect and uniformity of hydrogen and natural gas.

[0058] Combustion system 2 may include a burner, a fuel passage and an air passage; the burner may be located in the chamber formed by the extension section 205, the combustion section 206 and the retracted section 207, and other necessary structures may be achieved by conventional burner technology; the fuel passage may be achieved by the fuel inlet 201 and the air passage may be achieved by the air supply component 204. Specifically, air is introduced through air inlet 2041 and distributed to the burner through air pipe 2042. A blend of natural gas and hydrogen fuel is introduced through fuel inlet 201, fully mixed with air, and then enters the burner for combustion. The fuel channel includes a mixing section, which is a blending component 1. Natural gas and hydrogen are mixed in the mixing section. The mixing section is connected to a natural gas delivery pipe 101 and a hydrogen delivery pipe 102, which are integral structures. The hydrogen delivery pipe 102 is inserted into the natural gas delivery pipe 101. The cross-section of the hydrogen delivery pipe 102 is an equilateral triangle, making it an equilateral triangle structure. The equilateral triangle structure is symmetrically distributed along the axis of the natural gas delivery pipe 101. The first angle of the equilateral triangle structure is located at the center of the upstream side of the natural gas delivery pipe 101, and the first face corresponding to the first angle is located downstream of the natural gas delivery pipe 101. A hydrogen outlet 1022 for hydrogen output is located on the first face.

[0059] Understandably, because the triangular hydrogen delivery pipe 102 is a turbulent flow relative to the natural gas flow, the natural gas will experience vortex turbulence as it passes through this structure, thus enhancing the mixing with hydrogen. Furthermore, the turbulent flow of natural gas through this structure creates negative pressure on the surface directly opposite the natural gas flow (the surface where the flute-shaped orifice is located), allowing hydrogen to be introduced at a pressure lower than the natural gas pressure. Compared to traditional circular pipes as hydrogen inlet pipes, the triangular design generates higher frequency vortices and stronger turbulence at its rear, resulting in a more efficient mixing effect. This also shortens the mixing distance, saving pipeline and installation space.

[0060] The blending component 1 in this embodiment also includes other technical features of the blending component 1 in Embodiment 1 and / or Embodiment 2, which will not be described in detail here.

[0061] This embodiment provides a method for hydrogen blending using a triangular cross-section flute tube, which uses the triangular cross-section flute tube hydrogen blending assembly as described in Embodiment 1 and / or Embodiment 2. The method includes: generating vortex turbulence at the hydrogen delivery pipe 102 inside the natural gas delivery pipe 101 to blend natural gas and hydrogen; and simultaneously, generating negative pressure at the surface where the hydrogen outlet 1022 is located to introduce hydrogen.

[0062] Preferably, the hydraulic diameter D1 of the natural gas pipeline 101 is 3 - 7 times, preferably 5 - 6 times, the hydraulic diameter D2 of the hydrogen pipeline 102; the hydrogen flow velocity V1 is 1.1 - 1.7 times the natural gas flow velocity V2. The above velocities and pipe diameters are optimized structures through simulation and experiments. This experiment uses a qualitative analysis method to conduct experiments on hydrogen pipelines with different hydraulic diameters, and it is found that when the ratio of the hydraulic diameter of the natural gas pipeline 101 to the hydraulic diameter of the hydrogen pipeline 102 increases or decreases, the mixing effect deteriorates.

[0063] Preferably, D1 / D2 = a * V1 / V2, where 1.8 < a < 7, and further preferably, 3 < a < 5. The above ratios of velocity and pipe diameter are optimized structures through simulation and experiments. The ratio of pipe diameter to velocity cannot be too large or too small, as either will result in poor mixing. When the ratio of pipe diameter to velocity reaches the optimal ratio, the mixing ratio of hydrogen and natural gas is the best.

[0064] As an improvement, the size parameters of the hydrogen pipeline 102 and the natural gas pipeline 101, the hydrogen flow velocity and the natural gas flow velocity, are preferably as follows:

[0065] The diameter of the natural gas pipeline 101: 250 - 350 mm, the natural gas flow velocity 6 - 8 m / s; preferably the length is 2200 - 2800 mm. The hydraulic diameter of the hydrogen pipeline 102 is 55 - 75 mm, and the hydrogen flow velocity is 8 - 11 m / s. The above dimensions are the results of a large number of numerical simulations and experiments. By selecting the above dimensions, the best mixing effect can be achieved.

[0066] The present invention also has the following technical effects for low-density hydrogen:

[0067] Strengthen airflow disturbance and turbulent mixing. The triangular column structure has a unique flow interference effect. Especially the vortices (Karman vortex street) formed behind the column can enhance the turbulence degree of the airflow. For low-density hydrogen, it is more likely to appear stratified or unevenly distributed in the flow field. The triangular flow disturbance column can accelerate the contact and mixing of hydrogen and natural gas by generating and maintaining strong vortices. The low-density hydrogen is quickly pulled into these turbulent regions, and the collision between gas molecules is strengthened through the vortices, thereby improving the mixing efficiency.

[0068] Low-pressure area and hydrogen diffusion. The low-pressure area behind the triangular column, combined with the characteristics of low-density hydrogen, provides favorable conditions for the diffusion of hydrogen. Due to its lower density, hydrogen is more likely to quickly diffuse in the low-pressure area than natural gas. This design utilizes the attracting effect of the low-pressure area to prompt hydrogen to quickly enter the vortex region and achieve uniform mixing with natural gas in a short time, avoiding the problem of uneven flow that may be caused by the relatively small density of hydrogen.

[0069] The shear layer effect enhances mixing. The high-speed shear layer formed behind the triangular turbulence column, coupled strongly with hydrogen, further improves mixing efficiency. The shear layer, by providing a strong velocity gradient, forcefully pushes hydrogen and natural gas towards each other, increasing the contact area between the two gases. This is particularly important for hydrogen, as its lower density makes it prone to stratification at lower flow rates; the high-speed movement of the shear layer effectively breaks up this stratification, achieving rapid and uniform mixing.

[0070] The turbulence design enhances hydrogen stability. Due to its low density and high diffusivity, hydrogen is prone to uneven distribution in the airflow, potentially leading to localized hydrogen enrichment or depletion, which affects the stability of the combustion process. The triangular turbulence column enhances the turbulence effect by altering the flow field structure, reducing the uneven distribution of hydrogen. Under the influence of the column, hydrogen avoids excessive stratification through vortices and shear layers, ensuring mixing stability.

[0071] The above description is merely a preferred embodiment of this practice and is not intended to limit the scope of this practice. Various modifications and variations can be made to this practice by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this practice should be included within the protection scope of this practice.

Claims

1. A triangular cross-section flute-shaped tube hydrogen blending and combustion system, characterized in that, It includes a fuel inlet (201), a combustion section (206) connected to the fuel inlet, and a system outlet (203) connected to the combustion section (206); a mixing component (1) is provided in the fuel inlet (201); the mixing component (1) includes a natural gas transmission pipe (101) and a hydrogen transmission pipe (102); The natural gas transmission pipe (101) has an insertion hole (1012), and the hydrogen transmission pipe (102) extends through the insertion hole (1012) into the natural gas transmission pipe (101); the portion of the hydrogen transmission pipe (102) located inside the natural gas transmission pipe (101) has a hydrogen outlet (1022); the hydrogen transmission pipe (102) has a triangular cross-section in the vertical length direction, one corner of the hydrogen transmission pipe (102) faces the natural gas inlet (1011) of the natural gas transmission pipe (101), and the hydrogen outlet (1022) is located on the side of the hydrogen transmission pipe (102) away from the natural gas inlet (1011).

2. The triangular cross-section flute-shaped tube hydrogen blending and combustion system as described in claim 1, characterized in that, On the side of the hydrogen delivery pipe (102) opposite to the natural gas delivery pipe (101), there are multiple hydrogen outlets (1022); in the vertical direction from top to bottom, the flow area of ​​the hydrogen outlets (1022) becomes larger and larger, and the magnitude of the increase is constantly increasing.

3. The triangular cross-section flute-shaped tube hydrogen blending and combustion system as described in claim 1, characterized in that, The hydrogen delivery pipe (102) is inclinedly disposed on the natural gas delivery pipe (101).

4. The triangular cross-section flute-shaped tube hydrogen blending and combustion system as described in claim 1, characterized in that, The combustion section (206) is a horizontal section, and an extension section (205) connects the fuel inlet (201) to the combustion section (206); a recess section (207) connects the combustion section (206) to the system outlet (203).

5. The triangular cross-section flute-shaped tube hydrogen blending and combustion system as described in claim 4, characterized in that, An air supply unit (204) is provided outside the area where the extension section (205), the combustion section (206), and the retraction section (207) are located.

6. The triangular cross-section flute-shaped tube hydrogen blending and combustion system as described in claim 5, characterized in that, The air supply unit (204) includes an air duct (2042) and a first air inlet (2043), a second air inlet (2044), and a third air inlet (2045) located on the air duct (2042) at the positions of the recessed section (207), the combustion section (206), and the extended section (205), respectively; the air inlet (2041) on the air duct (2042) is close to the system outlet (203), and the air outlet (2046) on the air duct (2042) is close to the fuel inlet (201).

7. A triangular cross-section flute-shaped tube hydrogen-natural gas blending assembly, characterized in that, Includes a natural gas pipeline (101) and a hydrogen pipeline (102); The natural gas transmission pipe (101) has an insertion hole (1012), and the hydrogen transmission pipe (102) extends through the insertion hole (1012) into the natural gas transmission pipe (101); the portion of the hydrogen transmission pipe (102) located inside the natural gas transmission pipe (101) has a hydrogen outlet (1022); the hydrogen transmission pipe (102) has a triangular cross-section in the vertical length direction, one corner of the hydrogen transmission pipe (102) faces the natural gas inlet (1011) of the natural gas transmission pipe (101), and the hydrogen outlet (1022) is located on the side of the hydrogen transmission pipe (102) away from the natural gas inlet (1011).

8. The triangular cross-section flute-shaped hydrogen mixing assembly as described in claim 7, characterized in that, Multiple hydrogen outlets (1022) are provided on the side of the hydrogen transmission pipe (102) opposite to the natural gas transmission pipe (101).

9. A triangular cross-section flute-shaped hydrogen mixing assembly as described in claim 7, characterized in that, The hydrogen delivery pipe (102) is inclinedly disposed on the natural gas delivery pipe (101).

10. A method for mixing hydrogen gas in a triangular cross-section flute-shaped tube, characterized in that, The triangular cross-section flute tube hydrogen mixing assembly as described in any one of claims 7-9 is used, comprising: generating vortex turbulence at the hydrogen transmission pipe (102) within the natural gas transmission pipe (101) to mix natural gas and hydrogen; simultaneously, the natural gas turbulence generates negative pressure at the surface where the hydrogen outlet (1022) is located to introduce hydrogen.

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