Gas-liquid phase mixing coaxial staged micro-mix array nozzle combustor

Abstract

This invention discloses a gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner, comprising multiple nozzle units. Each nozzle unit includes a central channel, a first combustion-supporting channel, a second mixing channel, an injection channel, and a swirl element. One end of the central channel forms a central nozzle on the injection surface. The first combustion-supporting channel surrounds the central channel. The second mixing channel surrounds the first combustion-supporting channel. One end of the injection channel is located on the inner wall of the second mixing channel and forms an injection hole. On the injection surface, the first combustion-supporting outlet and the second mixing channel outlet are annular and coaxially arranged. The first radial width of the first combustion-supporting outlet is x1, and the second radial width of the second mixing channel outlet is x2, where x1 > x2. This gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner can reduce the occurrence of backfire, improve the uniformity of combustion temperature, and reduce the generation of pollutants.

Description

Technical Field

[0001] This invention relates to the field of combustion equipment technology, and in particular to a gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner. Background Technology

[0002] With the implementation of dual-carbon goals, there is a demand for low-carbon combustion technologies. The mixed use of gaseous and liquid fuels can meet these low-carbon requirements. For example, hydrogen, a gaseous fuel, is hailed as the ultimate low-carbon energy source of the 21st century, possessing excellent properties such as high energy density, high calorific value, and zero carbon emissions. However, compared to conventional fuels, hydrogen flames propagate faster and are prone to backfire or thermoacoustic instability, posing challenges to burner design.

[0003] In related technologies, the carbon emissions from traditional aviation kerosene will still double, far from meeting emission reduction targets. Limited by the development of related technologies, the combustion technology of mixed gaseous and liquid fuels (such as the combustion technology of kerosene mixed with hydrogen fuel) is still in its early stages in the aviation field and will become a key direction for future development. Therefore, the combustion technology of mixed gaseous and liquid fuels is one of the key technologies for solving low-carbon issues in the aviation field and is of great significance for emission reduction. However, for example, the physicochemical properties and combustion characteristics of large-molecule liquid aviation kerosene and small-molecule gaseous hydrogen differ greatly. The combustion of liquid hydrocarbon fuels requires atomization, evaporation, and mixing with air. The flame propagation speed is slow, requiring components (such as flame stabilizers) to create a backflow low-speed zone for flame stabilization; however, due to the high diffusion rate and strong reactivity of hydrogen, the flame propagation speed is fast, making backfire problems prone to occur in the low-speed zone. Summary of the Invention

[0004] This application provides a gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner, which can reduce the occurrence of backfire, improve the stability of combustion and the uniformity of combustion temperature, and reduce the generation of pollutants.

[0005] This application provides a gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner, including multiple nozzle units discretely arranged on the same injection surface. Each nozzle unit includes: a central channel, one end of which forms a central nozzle on the injection surface, and the other end of which is a liquid fuel inlet; a first combustion-supporting channel, which surrounds the central channel, one end of which forms a first combustion-supporting outlet on the injection surface, and the other end of which is a first combustion-supporting inlet for introducing combustion air; and a second mixing channel, which surrounds the first combustion-supporting channel, one end of which forms a second mixing channel outlet on the injection surface. The second mixing channel has an inlet at one end for introducing combustion air; an injection channel, one end of which is located on the inner wall of the second mixing channel and forms an injection hole, and the other end of which is a gaseous fuel inlet; a swirling element, which is fluidly disposed in the first combustion channel to cause the combustion air flowing out from the first combustion outlet to swirl around the central nozzle; wherein, on the injection surface, the first combustion outlet and the second mixing channel outlet are annular and coaxially arranged, and the axis of the first combustion outlet is on the central nozzle; half of the difference between the outer diameter and the inner diameter of the first combustion outlet is the first radial width x1, and half of the difference between the outer diameter and the inner diameter of the second mixing channel outlet is the second radial width x2, where x1 > x2.

[0006] In the above technical solution, the inner wall of the second mixing channel is provided with injection holes. The injection channel can send gaseous fuel into the second mixing channel through the injection holes, so that the combustion air and gaseous fuel in the second mixing channel are mixed. This pre-mixing of gaseous fuel and combustion air in the second mixing channel can achieve pre-mixed combustion of gaseous fuel and combustion air, which can make the combustion temperature of the gaseous fuel and combustion air mixture uniform and effectively reduce the occurrence of high temperature hot spots during combustion, thereby reducing pollutant emissions. Secondly, the first radial width is greater than the second radial width, that is, the radial width of the first combustion outlet is greater than the radial width of the second mixing channel outlet. When combustion air is introduced into the first combustion channel and the second mixing channel, the gas flow velocity of the gaseous fuel and combustion air mixture ejected from the outlet of the second mixing channel is greater than the gas flow velocity of the combustion air ejected from the outlet of the first combustion outlet, which can effectively reduce the occurrence of backfire at the outlet of the second mixing channel. Therefore, by pre-mixing the gaseous fuel and combustion air in the second mixing channel, and with the high gas flow velocity of the gaseous fuel and combustion air mixture at the outlet of the second mixing channel, backfire can be effectively prevented. In addition, the jet shear layer formed by the combustion of the mixed gas on one side of the injection surface can stabilize the flame. As a result, the combustion of the gaseous fuel and combustion air mixture is stable and the combustion temperature is uniform, effectively reducing the generation of pollutants.

[0007] In some embodiments of this application, in each nozzle unit, a plurality of injection holes are formed on the inner wall of the second mixing channel, the plurality of injection holes are evenly spaced along the circumference, and each injection hole is provided with a corresponding injection channel.

[0008] In some embodiments of this application, each nozzle unit further includes a distribution channel arranged around the second mixing channel, and the connection between the distribution channel and the injection channel constitutes the gas fuel inlet.

[0009] In some embodiments of this application, the central channel is straight, the first combustion-supporting channel and the second mixing channel are annular channels with progressively increasing diameters, and the central channel, the first combustion-supporting channel and the second mixing channel are coaxially arranged.

[0010] In some embodiments of this application, the swirling element is a swirler with multiple swirling blades, the multiple swirling blades being spaced apart around the central channel, the installation angle of the swirling blades being α, and satisfying 30°≤α≤60°; the swirler is coaxially arranged with the central channel, and the swirling degree of the swirler is 0.5-1.5.

[0011] In some embodiments of this application, the liquid fuel inlet of all the nozzle units is connected to the same main liquid channel.

[0012] In some embodiments of this application, the diameter of each nozzle unit is 10mm-30mm; the first radial width x1 of the first combustion outlet satisfies: 5mm≤x1≤30mm; the diameter D of the central nozzle satisfies: 3mm≤D≤6mm; and the second radial width x2 of the second mixing channel satisfies: 2mm≤x2≤10mm.

[0013] In some embodiments of this application, the central nozzle is conical with a cone angle of 20°-120°.

[0014] In some embodiments of this application, the diameter of a single spray hole is 0.2mm-2mm, 8-20 spray holes are arranged on the inner wall of each second mixing channel, and the distance between the spray hole and the spray surface is 10mm-50mm.

[0015] In some embodiments of this application, the spray surface is planar; the plurality of nozzle units are arranged in a circular, rectangular or fan-shaped pattern in one or more circles.

[0016] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0018] Figure 1 This is a schematic diagram of a gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner provided in some embodiments of this application;

[0019] Figure 2 This is another schematic diagram of a gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner provided in some embodiments of this application;

[0020] Figure 3 This is a cross-sectional view of a nozzle unit body provided in some embodiments of this application;

[0021] Figure 4 This is a schematic diagram of a nozzle unit body provided in some embodiments of this application;

[0022] Figure 5 This is a cross-sectional view of a gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner provided in some embodiments of this application.

[0023] Figure label:

[0024] Gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200, injection surface 101, combustion zone 102.

[0025] Nozzle unit 100

[0026] Central channel 1, central nozzle 11, nozzle body 11a, liquid fuel inlet 12

[0027] First combustion-supporting channel 2, First combustion-supporting outlet 21, First combustion-supporting inlet 22

[0028] Second mixing channel 3, second mixing channel outlet 31, second mixing channel inlet 32

[0029] Injection channel 4, injection hole 41, gas fuel inlet 42

[0030] Swirl component 5, swirl blade 51

[0031] Distribution Channel 6

[0032] Liquid main channel 71, liquid fuel supply pipe 72. Detailed Implementation

[0033] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0034] The following disclosure provides numerous different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. Additionally, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0035] Hereinafter, with reference to the accompanying drawings, a gas-liquid phase mixing coaxial graded micro-mixing array nozzle burner 200 according to an embodiment of the present invention will be described.

[0036] like Figure 1 and Figure 3 As shown, the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 includes multiple nozzle units 100, which are discretely arranged on the same injection surface 101. For example, combined with Figure 1 and Figure 2 The surface of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 on one side of the axial direction is the injection surface 101, and multiple nozzle units 100 are arranged in a circle on the same injection surface 101 in one or more circles.

[0037] Each nozzle unit 100 includes a central channel 1, a first combustion-supporting channel 2, a second mixing channel 3, and an injection channel 4. One end of the central channel 1 forms a central nozzle 11 (e.g., a centrifugal nozzle) on the injection surface 101, and the other end of the central channel 1 is a liquid fuel inlet 12. The first combustion-supporting channel 2 is arranged around the central channel 1. One end of the first combustion-supporting channel 2 forms a first combustion-supporting outlet 21 on the injection surface 101, and the other end of the first combustion-supporting channel 2 is a first combustion-supporting inlet 22 to introduce combustion-supporting air. The second mixing channel 3 is arranged around the first combustion-supporting channel 2. One end of the second mixing channel 3 forms a second mixing channel outlet 31 on the injection surface 101, and the other end of the second mixing channel 3 is a second mixing channel inlet 32 ​​to introduce combustion-supporting air. One end of the injection channel 4 is located on the inner wall of the second mixing channel 3 and forms an injection hole 41. The other end of the injection channel 4 is a gaseous fuel inlet 42. Thus, when liquid fuel, combustion air, and gaseous fuel are introduced into the nozzle unit 100, the liquid fuel (e.g., kerosene) can flow from the liquid fuel inlet 12 into the central channel 1 and towards the central nozzle 11, and then the liquid fuel can be ejected from the central nozzle 11, forming a liquid fuel spray (e.g., kerosene spray); the combustion air (e.g., air or oxygen) can flow from the first combustion inlet 22 into the first combustion channel 2 and towards the first combustion outlet 21, and then the combustion air can be ejected from the first combustion outlet 21; and the combustion air (e.g., air) can flow from the second mixing channel inlet 32 ​​into the second mixing channel 3 and towards the second mixing channel outlet 31, and then the combustion air can be ejected from the second mixing channel outlet 31; the gaseous fuel flows through the injection channel 4 to the injection hole 41, and then the gaseous fuel is ejected from the injection hole 41 and flows into the second mixing channel 3, so that the gaseous fuel and the combustion air can be mixed in the second mixing channel 3 and ejected from the second mixing channel outlet 31.

[0038] It is understandable that, in a broad sense, combustion air refers to gases that support combustion, such as air or oxygen, or a mixture of other gases (such as non-combustible gases) and oxygen.

[0039] Each nozzle unit 100 also includes a swirling fluid disposed within the first combustion channel 2, so that the combustion air flowing from the first combustion outlet 21 swirls around the central nozzle 11. Thus, the swirling fluid can generate a swirling flow at the first combustion outlet 21, forming a recirculation zone on the injection surface 101, thereby enabling the combustion air to mix and burn with liquid fuel (e.g., liquid fuel spray) or with gaseous fuel, resulting in a more stable combustion process.

[0040] In this design, on the injection surface 101, the first combustion outlet 21 and the second mixing channel outlet 31 are annular and coaxially arranged. The axis of the first combustion outlet 21 is on the central nozzle 11, which allows the sprayed liquid fuel, combustion air and gaseous fuel to be approximately coaxially arranged with the combustion air mixture, so that the liquid fuel, combustion air and gaseous fuel can be better mixed evenly to ensure stable combustion.

[0041] Furthermore, half the difference between the outer and inner diameters of the first combustion outlet 21 is the first radial width x1, and half the difference between the outer and inner diameters of the second mixing channel outlet 31 is the second radial width x2, where x1 > x2. Therefore, when combustion air is introduced into the first combustion channel 2 and the second mixing channel 3, the gas flow velocity of the mixed gas (gas fuel and combustion air mixed in the second mixing channel 3) ejected from the second mixing channel outlet 31 is greater than the gas flow velocity of the combustion air ejected from the first combustion outlet 21. This effectively reduces the occurrence of backfire at the second mixing channel outlet 31, ensuring stable combustion of the gas fuel. Secondly, the relatively fast gas flow velocity of the mixed gas ejected from the second mixing channel outlet 31 results in a shorter residence time of the mixed gas (gas fuel and combustion air) within the second mixing channel 3, effectively reducing the probability of spontaneous combustion within the second mixing channel 3 and improving the safety of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200.

[0042] In some examples, combined Figure 3On the one hand, the inner wall of the second mixing channel 3 is provided with injection holes 41. The injection channel 4 can send gaseous fuel into the second mixing channel 3 through the injection holes 41. The combustion air introduced into the second mixing channel 3 flows from the inlet 32 ​​of the second mixing channel towards the outlet 31 of the second mixing channel, so that the combustion air and gaseous fuel are mixed in the second mixing channel 3 and then sprayed out together from the outlet 31 of the second mixing channel. This allows the gaseous fuel and combustion air to be premixed in the second mixing channel 3, which can realize the premixed combustion of gaseous fuel and combustion air. This makes the combustion temperature of the gaseous fuel and combustion air mixture uniform, effectively reducing the occurrence of high temperature hot spots during combustion, thereby reducing pollutant emissions (for example, high temperature hot spots will increase the emission of pollutants such as NOx). On the other hand, the first radial width is greater than the second radial width, that is, the radial width of the first combustion outlet 21 is greater than the radial width of the second mixing channel outlet 31. When combustion air is introduced into the first combustion channel 2 and the second mixing channel 3, the gas flow velocity of the gaseous fuel and combustion air mixture ejected from the second mixing channel outlet 31 is greater than the gas flow velocity of the combustion air ejected from the first combustion outlet 21, which can effectively reduce the occurrence of backfire at the second mixing channel outlet 31. Thus, by pre-mixing the gaseous fuel and combustion air in the second mixing channel 3, and ensuring a faster gas flow velocity of the gaseous fuel and combustion air mixture at the second mixing channel outlet 31, the nozzle unit 100 can effectively prevent backfire. Furthermore, the jet shear layer formed by the combustion of the mixed gas on one side of the injection surface 101 can stabilize the flame, thereby ensuring stable combustion of the gaseous fuel and combustion air mixture and uniform combustion temperature, effectively reducing the generation of pollutants.

[0043] Optionally, the first combustion-supporting outlet 21 is located on the side of the second mixing channel outlet 31 away from the central nozzle 11 (e.g., the second mixing channel outlet 31 is located radially outside the first combustion-supporting outlet 21). Combined Figure 3 The central nozzle 11 is located at the center of the nozzle unit 100, the second mixing channel outlet 31 is located at the outermost edge of the nozzle unit 100, and the first combustion-supporting outlet 21 is located between the central nozzle 11 and the second mixing channel outlet 31. Liquid fuel is sprayed from the center of the nozzle unit 100, and the mixture of gaseous fuel and combustion-supporting air (combustion-supporting air in the second mixing channel 3) is sprayed from the outermost edge of the nozzle unit 100. The combustion-supporting air (combustion-supporting air in the first combustion-supporting channel 2) is located between the mixed gas and the liquid fuel spray. Therefore, this application employs liquid fuel spray diffusion from the center of the nozzle unit 100, and the outermost gaseous fuel is first mixed with combustion-supporting air in the second mixing channel 3 before being sprayed from the second mixing channel outlet 31 (e.g., micro-premixed combustion technology). This can improve combustion stability and combustion temperature uniformity, thereby improving the flame stability of the nozzle unit 100 at low loads and reducing pollutant emissions at high loads.

[0044] In some examples, combined Figure 3 The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 includes multiple nozzle units 100, which are located on the same injection surface 101. Therefore, the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 disperses the mixing process of fuel (liquid fuel and gaseous fuel) with combustion air across multiple nozzle units 100. This reduces dependence on swirling mixing methods and, to some extent, avoids backfire caused by vortex breaking during combustion due to strong swirling. Furthermore, the relatively high airflow velocity within the second mixing channel 3 of the nozzle unit 100 effectively reduces boundary layer backfire and turbulent flame propagation backfire, thereby improving combustion stability. Secondly, multiple nozzle units 100 are located on the same injection surface 101, and mixing occurs between the multiple nozzle units 100 during combustion (for example, the fuel injected by multiple nozzle units 100 mixes with the combustion air). This results in a larger specific surface area and stronger heat loss in the premixing zone of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200, which is beneficial to improving the combustion performance of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200.

[0045] Optionally, the supply of combustion air, gaseous fuel, and liquid fuel to each nozzle unit 100 can be controlled independently. Thus, the supply ratio of combustion air, gaseous fuel, and liquid fuel in each nozzle unit 100 can be adjusted individually. That is, by adjusting the supply amount (e.g., flow rate) of combustion air, gaseous fuel, and liquid fuel in the nozzle unit 100, the combustion heat release of the nozzle unit 100 can be dynamically adjusted, which can effectively suppress the occurrence of combustion instability and improve the combustion stability of the nozzle unit 100 during operation.

[0046] Optionally, the supply amount (supply amount of combustion air, gaseous fuel, and liquid fuel) of all nozzle units 100 of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 can be controlled individually. The supply amount of different nozzle units 100 can be adjusted, thereby adjusting the output power of a single nozzle unit 100. This allows for more precise adjustment of the partial or overall output power of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200, better adapting to combustion and output power requirements under different conditions (e.g., different loads). Secondly, the number of nozzle units 100 in the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 can be adjusted to regulate its output power. Of course, by adjusting the output power of the nozzle unit 100 to regulate the temperature distribution on the injection surface 101, and by adjusting the flow rate of the fuel and combustion air supplied by the nozzle unit 100, the residence time of the fuel (liquid and gaseous fuel) on the injection surface 101 (e.g., combustion zone 102) can be adjusted, thereby synergistically controlling the generation of pollutants (NOx) and reducing pollutant emissions.

[0047] In the above technical solution, the inner wall of the second mixing channel 3 is provided with injection holes 41. The injection channel 4 can send gaseous fuel into the second mixing channel 3 through the injection holes 41, so that the combustion air and gaseous fuel in the second mixing channel 3 are mixed. This pre-mixing of gaseous fuel and combustion air in the second mixing channel 3 can achieve pre-mixed combustion of gaseous fuel and combustion air, which can make the combustion temperature of the gaseous fuel and combustion air mixture uniform and effectively reduce the occurrence of high temperature hot spots during combustion, thereby reducing pollutant emissions. Secondly, the first radial width is greater than the second radial width, that is, the radial width of the first combustion outlet 21 is greater than the radial width of the second mixing channel outlet 31. When combustion air is introduced into the first combustion channel 2 and the second mixing channel 3, the gas flow velocity of the gaseous fuel and combustion air mixture ejected from the second mixing channel outlet 31 is greater than the gas flow velocity of the combustion air ejected from the first combustion outlet 21, which can effectively reduce the occurrence of backfire at the second mixing channel outlet 31. Therefore, by pre-mixing the gaseous fuel and combustion air in the second mixing channel 3, and by ensuring that the gaseous fuel and combustion air mixture at the outlet 31 of the second mixing channel has a relatively high gas flow velocity, backfire can be effectively prevented. Furthermore, the jet shear layer formed by the combustion of the mixed gas on one side of the injection surface 101 can stabilize the flame. As a result, the combustion of the gaseous fuel and combustion air mixture is stable and the combustion temperature is uniform, effectively reducing the generation of pollutants.

[0048] Optionally, combustion air can be introduced into the first combustion inlet 22 and the second mixing channel inlet 32, and the airflow velocity of the combustion air introduced into the second mixing channel inlet 32 ​​is greater than the airflow velocity of the combustion air introduced into the first combustion inlet 22.

[0049] Alternatively, in other embodiments, the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 includes a nozzle unit 100.

[0050] In some embodiments of this application, such as Figure 3 As shown, in each nozzle unit 100, a plurality of injection holes 41 are formed on the inner wall of the second mixing channel 3. The plurality of injection holes 41 are evenly spaced along the circumference, and each injection hole 41 is provided with an injection channel 4.

[0051] Optionally, the shape of the injection hole 41 is not limited. For example, the shape of the injection hole 41 can be circular, rectangular, or elliptical.

[0052] In the above technical solution, multiple injection holes 41 are evenly spaced along the inner wall of the second mixing channel 3 so that the combustion air in the second mixing channel 3 can be mixed with the gaseous fuel in all parts of the circumference. This makes the mixing of combustion air and gaseous fuel in the second mixing channel 3 more uniform, which is conducive to more uniform and stable combustion of the mixed gas and can reduce the generation of pollutants.

[0053] In some embodiments of this application, such as Figure 3 and Figure 5 As shown, each nozzle unit 100 also includes a distribution channel 6, which surrounds the second mixing channel 3, and the connection between the distribution channel 6 and the injection channel 4 constitutes a gas fuel inlet 42.

[0054] For example, combining Figure 3 Each nozzle unit 100 also includes a distribution channel 6, which is arranged around the second mixing channel 3 and is connected to one end of the plurality of injection channels 4. The other end of each injection channel 4 is located on the inner wall of the second mixing channel 3 and forms an injection hole 41. The gaseous fuel is distributed to each injection channel 4 in the distribution channel 6 and flows into the second mixing channel 3 from the corresponding injection hole 41. Thus, the distribution channel 6 can ensure that the amount of gaseous fuel distributed to each injection channel 4 is equal, so as to ensure uniform mixing of combustion air and gaseous fuel in the second mixing channel 3. Secondly, the distribution channel 6 can alleviate the pressure fluctuation of the gaseous fuel inflow and improve the injection pressure stability and flow stability of the gaseous fuel in the plurality of injection holes 41.

[0055] In the above technical solution, the connection between the distribution channel 6 and the injection channel 4 corresponding to each nozzle unit 100 is beneficial to ensure that the amount of gaseous fuel distributed by the distribution channel 6 to each injection channel 4 is equal, so as to ensure that the combustion air and gaseous fuel are mixed evenly in the second mixing channel 3. Secondly, the distribution channel 6 can alleviate the fluctuation of the incoming gaseous fuel pressure and improve the injection pressure stability and flow stability of the gaseous fuel in the multiple injection holes 41.

[0056] In some embodiments of this application, such as Figure 3 As shown, the central channel 1 is a straight line, and the first combustion-supporting channel 2 and the second mixing channel 3 are annular channels with progressively increasing diameters, and the central channel 1, the first combustion-supporting channel 2, and the second mixing channel 3 are coaxially arranged.

[0057] For example, combining Figure 3 The central channel 1, the first combustion-supporting channel 2, and the second mixing channel 3 are coaxially arranged. The central channel 1 extends along a straight line to form a cylindrical structure. The first combustion-supporting channel 2 and the second mixing channel 3 are arranged sequentially from the inside to the outside along the central channel 1. The outer diameter of the second mixing channel 3 is larger than the outer diameter of the first combustion-supporting channel 2.

[0058] In the above technical solution, by setting the central channel 1, the first combustion-supporting channel 2, and the second mixing channel 3 coaxially, the gaseous fuel, combustion-supporting air, and liquid kerosene ejected from the nozzle unit 100 can be arranged approximately coaxially, which facilitates the mixing and combustion of gaseous fuel, combustion-supporting air, and liquid kerosene, and helps to improve the uniformity and stability of the combustion temperature.

[0059] In some embodiments of this application, combined with Figure 3 and Figure 4 The swirling element 5 is a swirler with multiple swirling blades 51. The multiple swirling blades 51 are arranged at intervals around the central channel 1. The installation angle of the swirling blades 51 is α, and satisfies 30°≤α≤60°.

[0060] Optionally, the swirler is coaxially arranged with the central channel 1, and the swirling degree of the swirler is 0.5-1.5. Thus, by setting the swirling degree of the swirler within a suitable range, it is beneficial to the combustion stability of the nozzle unit 100 at the injection surface 101, and at the same time, it effectively reduces the occurrence of backfire.

[0061] Optionally, the installation angle of the swirl blade 51 can be 30°, 45°, 50°, 55°, or 60°, etc.; the swirl intensity of the cyclone can be 0.5, 0.8, 1, 1.2, or 1.5, etc.

[0062] In the above technical solution, by setting the installation angle of the swirl blade 51 within a suitable range, the swirl element 5 can better drive the combustion air to generate a recirculation zone at the first combustion outlet 21, so as to better stabilize the flame.

[0063] In some embodiments of this application, combined with Figure 5 All nozzle units 100 have liquid fuel inlets 12 connected to the same liquid main channel 71.

[0064] For example, combining Figure 5 The liquid main channel 71 is connected to the liquid fuel inlet 12 of all nozzle units 100. The liquid fuel is diverted through the liquid main channel 71 to the liquid fuel inlet 12 of all nozzle units 100, and then the liquid fuel flows from the liquid fuel inlet 12 into the central channel 1 and is ejected from the central nozzle 11.

[0065] Optionally, the flow channel diameter of the liquid main channel 71 is 1mm-10mm.

[0066] In the above technical solution, by setting the liquid fuel inlet 12 of all nozzle units 100 to be connected to the same liquid main channel 71, it is possible to ensure that the pressure of the liquid fuel flowing to the liquid fuel inlet 12 of all nozzle units 100 is equal. This is beneficial to ensure that the amount of liquid fuel distributed from the liquid main channel 71 to all nozzle units 100 is equal, and can improve the flame stability of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 during operation.

[0067] In some embodiments of this application, combined with Figure 3 The diameter of each nozzle unit 100 is 10mm-30mm; the first radial width x1 of the first combustion outlet 21 satisfies: 2mm≤x1≤10mm; the diameter D of the center nozzle 11 satisfies: 3mm≤D≤6mm; the second radial width x2 of the second mixing channel 3 satisfies: 5mm≤x2≤30mm.

[0068] Optionally, the diameter of each nozzle unit 100 can be 10mm, 15mm, 20mm, 25mm, or 30mm, etc.; the first radial width of the first combustion outlet 21 can be 2mm, 4mm, 5mm, 7mm, 8mm, or 10mm, etc.; the diameter of the center nozzle 11 can be 3mm, 4mm, 5mm, or 6mm, etc.; and the second radial width of the second mixing channel 3 can be 5mm, 8mm, 10mm, 15mm, 20mm, 25mm, or 30mm, etc.

[0069] In the above technical solution, by setting the diameter of each nozzle unit 100 within a suitable range, it is beneficial to reduce the risk of backfire in the nozzle unit 100 and facilitate the dense arrangement of multiple nozzle units 100; by setting the first radial width of the first combustion outlet 21 within a suitable range, it is ensured that the first combustion outlet 21 sprays out suitable combustion air, which is beneficial to more complete combustion and improved combustion stability; by setting the diameter of the central nozzle 11 within a suitable range, it is ensured that the central nozzle 11 can spray out suitable liquid fuel, and it is beneficial to the atomization of liquid fuel, which facilitates the mixing and combustion of liquid fuel with combustion air; by setting the second radial width of the second mixing channel 3 within a suitable range, it is beneficial to increase the gas flow rate in the second mixing channel 3 and to make the second mixing channel 3 form a slit-like channel, so that the combustion air and gaseous fuel are mixed in the second mixing channel 3, and a jet shear layer is formed on the injection surface 101, which can better stabilize the flame.

[0070] Optionally, the inner wall of the second mixing channel 3 is provided with injection holes 41. Gaseous fuel flows into the second mixing channel 3 from the injection holes 41 and mixes with the combustion air in the second mixing channel 3. Since the second radial width of the outlet 31 of the second mixing channel is small, the mixing effect of gaseous fuel and combustion air in the second mixing channel 3 can be improved, making the mixture more uniform and achieving a more uniform combustion temperature field, further reducing the occurrence of local high-temperature zones during combustion. For example, compared to some technologies where the outlet size of the second mixing channel is larger and swirl flow is generally used for flame stabilization combustion, in this embodiment of the application, the outlet size of the second mixing channel 31 is smaller, and premixing technology (gaseous fuel and combustion air are premixed in the second mixing channel 3) is used, which can further enhance the premixing effect, making the combustion temperature of the mixed gas more uniform and effectively avoiding the occurrence of local high-temperature zones.

[0071] In some embodiments of this application, the central nozzle 11 is conical with a cone angle of 20°-120°.

[0072] For example, the central nozzle 11 is conical with a cone angle between 20° and 120°, which allows the liquid fuel spray from the central nozzle 11 to form a conical structure with a cone angle between 20° and 120°. This facilitates better mixing and combustion of the liquid fuel spray with the combustion air, which is beneficial for improving the uniformity of combustion temperature.

[0073] In the above technical solution, by setting the central nozzle 11 to be conical and the cone angle to be at a suitable cone angle, the liquid fuel spray ejected from the central nozzle 11 is in a suitable shape (e.g., a conical structure) and the cone angle of the liquid fuel spray is in a suitable range, which facilitates better mixing and combustion of the liquid fuel spray with the combustion air and helps to improve the uniformity of combustion temperature.

[0074] In some embodiments of this application, combined with Figure 3 The diameter of a single injection hole 41 is 0.2mm-2mm. 8-20 injection holes 41 are arranged on the inner wall of each second mixing channel 3. The distance between the injection hole 41 and the injection surface 101 is 10mm-50mm.

[0075] For example, combining Figure 3 Both the first combustion channel 2 and the second mixing channel 3 are formed as annular channels, and the second mixing channel 3 is located radially outside the first combustion channel 2. Multiple injection holes 41 are arranged on the inner wall of the second mixing channel 3 away from the first combustion channel 2. The multiple injection holes 41 are arranged equidistantly along the circumference of the second mixing channel 3 to form a ring on the inner wall of the second mixing channel 3. A certain distance is spaced between the injection holes 41 and the injection surface 101 in the axial direction of the second mixing channel 3 so that the gaseous fuel ejected from the injection holes 41 can be mixed with the combustion air at a suitable distance, which is beneficial to improving the uniformity of the combustion temperature of the mixed gas and reducing the generation of pollutants.

[0076] Optionally, the diameter of a single spray hole 41 can be 0.2mm, 0.5mm, 0.8mm, 1mm, 1.5mm, or 2mm, etc.; the distance between the spray hole 41 and the spray surface 101 can be 10mm, 15mm, 20mm, 30mm, 40mm, or 50mm, etc.

[0077] In the above technical solution, by setting the diameter of the injection hole 41 within a suitable range, the appropriate gaseous fuel ejected from the injection hole 41 can be mixed with the combustion air in the second mixing channel 3, thereby improving the uniformity of the mixture. By arranging an appropriate number of injection holes 41 on the inner wall of each second mixing channel 3, the two adjacent injection holes 41 in the circumferential direction of the second mixing channel 3 can have an appropriate circumferential distance, which facilitates the full mixing of gaseous fuel and combustion air in the second mixing channel 3. By setting the distance between the injection hole 41 and the injection surface 101 within a suitable range, the injection hole 41 and the injection surface 101 in the second mixing channel 3 can have an appropriate distance, allowing the gaseous fuel and combustion air to mix at an appropriate distance, thereby improving the uniformity of the mixture and thus helping to improve the uniformity of the combustion temperature of the mixed gas and reduce the generation of pollutants.

[0078] In some embodiments of this application, combined with Figure 5 The spray surface 101 is a plane; multiple nozzle units 100 are arranged in a circle, rectangle or fan shape in one or more circles.

[0079] For example, combining Figure 5 The injection surface 101 of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 is formed as a plane. Multiple nozzle units 100 are arranged in a circle, rectangle or fan shape in one or more circles on the injection surface 101. Thus, when multiple nozzle units 100 are working, the multiple flames formed by the combustion of multiple nozzle units 100 on the injection surface 101 form a planar flame, which can effectively shorten the overall flame length and reduce or avoid the formation of large-scale backflow zones. This can reduce the residence time of reactants in the high-temperature zone, thereby reducing the generation of pollutants (such as NOx) and thus reducing pollutant emissions.

[0080] Optionally, the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 has 10-36 nozzle units 100.

[0081] In the above technical solution, by setting the spray surface 101 as a plane, multiple flames formed by the combustion of multiple nozzle units 100 on the spray surface 101 can form a planar flame, which can effectively shorten the overall flame length and reduce or avoid the formation of large-scale backflow zones, thereby reducing the residence time of reactants in the high-temperature zone, which can reduce the generation of pollutants (such as NOx) and reduce pollutant emissions.

[0082] Optionally, the minimum boundary distance between two adjacent nozzle units 100 is 5mm-10mm, which makes it easy for the minimum boundary distance between two adjacent nozzle units 100 to be within a suitable range. This allows for a compact arrangement of multiple nozzle units 100, that is, a compact flame distribution of each nozzle unit 100. This can improve the uniformity of the outlet temperature distribution of the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 located on the injection surface 101, and to a certain extent avoid interference (such as flame interaction between multiple nozzle units 100), which is beneficial to achieving stable flame combustion.

[0083] Of course, the number of nozzle units 100 and the distance between two adjacent nozzle units 100 (e.g., minimum boundary distance) can be adjusted according to the power (e.g., output power) and outlet temperature requirements of the gas-liquid phase mixing coaxial graded micro-mixing array nozzle burner 200. Furthermore, the component distribution of the nozzle units 100 on the injection surface 101 can be changed by adjusting the arrangement of the nozzle units 100.

[0084] The following is for reference. Figures 1-5A gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 according to an embodiment of the present invention is described in detail with reference to a specific example. It is to be understood that the following description is merely illustrative and not a specific limitation of the invention.

[0085] like Figures 1-5 As shown, the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 has an injection surface 101 formed at one axial end. The injection surface 101 is planar, and the downstream side of the injection surface 101 is the combustion zone 102 in the direction of airflow. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 includes multiple nozzle units 100, which are arranged in a circular and equidistant ring (or two rings) on the injection surface 101. Each nozzle unit 100 includes a central channel 1, a first combustion-supporting channel 2, and a second mixing channel 3. The central channel 1 is straight and has a cylindrical structure, while the first combustion-supporting channel 2 and the second mixing channel 3 have an annular structure. The central channel 1, the first combustion-supporting channel 2, and the second mixing channel 3 are coaxial and arranged sequentially from the inside to the outside along the radial direction of the central channel 1.

[0086] Each nozzle unit 100 also includes a distribution channel 6 and multiple injection channels 4. The distribution channel 6 is arranged around the second mixing channel 3 and is connected to the multiple injection channels 4. The connection between the distribution channel 6 and the injection channels 4 forms a gaseous fuel inlet 42. Multiple injection holes 41 are formed on the inner wall of the second mixing channel 3. The multiple injection holes 41 are arranged evenly spaced along the circumference of the second mixing channel 3. One end of the injection channel 4 is located on the inner wall of the second mixing channel 3 and forms an injection hole 41. A nozzle body 11a is provided in the central channel 1. The nozzle body 11a forms a central nozzle 11. The central nozzle 11 is located on the injection surface 101 and is connected to the central channel 1. A liquid fuel inlet 12 is formed at the end of the central channel 1 away from the central nozzle 11. The first combustion-supporting channel 2 forms a first combustion-supporting outlet 21 and a first combustion-supporting inlet 22. The second mixing channel 3 forms a second mixing channel outlet 31 and a second mixing channel inlet 32. The first combustion-supporting outlet 21 and the second mixing channel outlet 31 are both located on the injection surface 101. The first combustion channel 2 is provided with a swirl element 5 so that the combustion air flowing out from the first combustion outlet 21 swirls around the central nozzle 11.

[0087] The first combustion-supporting outlet 21 and the second mixing channel outlet 31 are annular and coaxially arranged. The axis of the first combustion-supporting outlet 21 is on the central nozzle 11. The central nozzle 11, the first combustion-supporting outlet 21 and the second mixing channel outlet 31 are also coaxially arranged. The first radial width of the first combustion-supporting outlet 21 is greater than the second radial width of the second mixing channel outlet 31. The second radial width of the second mixing channel 3 is between 2 mm and 10 mm. That is, the second mixing channel 3 is formed as an annular slit channel.

[0088] In addition, the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 also includes a combustion air supply structure, a gas fuel supply structure, and a liquid fuel supply structure. The combustion air supply structure can supply combustion air to the first combustion inlet 22 and the second mixing channel outlet 31 of the multiple nozzle units 100. The combustion air entering the first combustion inlet 22 flows along the first combustion channel 2, first through the swirl element 5, and finally flows from the first combustion outlet 21 to the combustion zone 102. The combustion air entering the second mixing channel inlet 32 ​​flows along the second mixing channel 3 and from the first combustion outlet 21 to the combustion zone 102. The gas fuel supply structure includes a gas fuel supply manifold, and the gas fuel supply manifold connects to the multiple nozzle units. When the distribution channel 6 of the body 100 is connected, the gaseous fuel entering the distribution channel 6 flows into the second mixing channel 3 from the injection hole 41. The gaseous fuel mixes with the combustion air in the second mixing channel 3 and flows together from the first combustion outlet 21 to the combustion zone 102. The liquid fuel supply structure includes a liquid main channel 71 and multiple liquid fuel supply pipes 72. Each liquid fuel supply pipe 72 is connected to the liquid fuel inlet 12 of a corresponding nozzle unit body 100. The liquid fuel is distributed from the liquid main channel 71 to the multiple liquid fuel supply pipes 72, and then flows from the liquid fuel inlet 12 to the nozzle body 11a and is sprayed out from the central nozzle 11 to form a conical liquid fuel spray in the combustion zone 102.

[0089] For example, taking kerosene (e.g., aviation kerosene) as the liquid fuel, air as the combustion air, and hydrogen as the gaseous fuel as an example, combined with... Figure 3 and Figure 5 In the combustion zone 102 corresponding to each nozzle unit 100, the kerosene spray from the central nozzle 11 is located at the center, the mixed gas from the second mixing channel outlet 31 is located at the outermost position, and the air from the first combustion-supporting outlet 21 is located between the kerosene spray and the mixed gas.

[0090] Hydrogen gas flows into the second mixing channel 3 through the injection hole 41 and mixes with air within the second mixing channel 3 (premixing technology). The second mixing channel 3 is formed as an annular slit channel (micro-mixing technology), which can be understood as an annular slit micro-premixing channel. This allows the hydrogen-air mixture to form a jet shear layer in the combustion zone 102. The jet shear layer can stabilize the flame combustion of the corresponding nozzle unit 100 in the combustion zone 102. At the same time, the gas flow velocity of the mixed gas at the outlet 31 of the second mixing channel is fast, and the residence time in the second mixing channel 3 is short, which can effectively reduce the occurrence of backfire and spontaneous combustion. Secondly, the air ejected from the first combustion outlet 21 of the first combustion-supporting channel 2 passes through the swirl element 5 to form a recirculation zone in the combustion zone 102. This allows the kerosene spray ejected from the central nozzle 11 to mix and burn with air, as well as the mixed gas to burn with air, which can improve the uniformity of combustion temperature and reduce the generation of pollutants.

[0091] As can be seen, downstream of the nozzle unit 100, a central swirling kerosene combustion zone and an outer shear layer hydrogen mixing combustion zone are formed in the direction of airflow. Of course, the gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner 200 of this embodiment can achieve the mixed combustion of hydrogen and kerosene, which is beneficial for reducing carbon emissions.

[0092] In the description of this invention, it should be understood that the terms "center," "length," "width," "upper," "lower," "front," "rear," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0093] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0094] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0095] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner, characterized in that, It includes multiple nozzle units, which are discretely arranged on the same spray surface; each nozzle unit includes: A central channel, one end of which forms a central nozzle on the injection surface, and the other end of which is a liquid fuel inlet; The first combustion-supporting channel is arranged around the central channel. One end of the first combustion-supporting channel forms a first combustion-supporting outlet on the injection surface, and the other end of the first combustion-supporting channel is a first combustion-supporting inlet to introduce combustion-supporting air. A second mixing channel is arranged around the first combustion-supporting channel. One end of the second mixing channel forms a second mixing channel outlet on the injection surface, and the other end of the second mixing channel is a second mixing channel inlet to introduce combustion-supporting air. An injection channel, one end of which is located on the inner wall of the second mixing channel and forms an injection hole, and the other end of which is a gaseous fuel inlet; A swirling element is disposed within the first combustion channel to cause combustion air flowing out of the first combustion outlet to swirl around the central nozzle. Wherein, on the spray surface, the first combustion-supporting outlet and the second mixing channel outlet are annular and coaxially arranged, and the axis of the first combustion-supporting outlet is on the central nozzle; Half of the difference between the outer diameter and the inner diameter of the first combustion-supporting outlet is the first radial width x1, and half of the difference between the outer diameter and the inner diameter of the second mixing channel outlet is the second radial width x2, where x1 > x2.

2. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to claim 1, characterized in that, In each nozzle unit, a plurality of injection holes are formed on the inner wall of the second mixing channel. The plurality of injection holes are evenly spaced along the circumference, and each injection hole is provided with a corresponding injection channel.

3. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to claim 2, characterized in that, Each of the nozzle units also includes a distribution channel arranged around the second mixing channel, the connection between the distribution channel and the injection channel forming the gas fuel inlet.

4. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to claim 1, characterized in that, The central channel is straight, and the first combustion-supporting channel and the second mixing channel are annular channels with progressively increasing diameters, and the central channel, the first combustion-supporting channel, and the second mixing channel are coaxially arranged.

5. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to claim 1, characterized in that, The swirling element is a swirling device with multiple swirling blades, which are spaced apart around the central channel. The installation angle of the swirling blades is α, and satisfies 30°≤α≤60°.

6. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to claim 1, characterized in that, The liquid fuel inlets of all the nozzle units are connected to the same main liquid channel.

7. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to claim 1, characterized in that, The diameter of each nozzle unit is 10mm-30mm; The first radial width x1 of the first combustion outlet satisfies: 5mm≤x1≤30mm; The diameter D of the central nozzle satisfies: 3mm≤D≤6mm; The second radial width x2 of the second mixing channel satisfies: 2mm≤x2≤10mm.

8. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to claim 1, characterized in that, The central nozzle is conical with a cone angle of 20°-120°.

9. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to claim 1, characterized in that, The diameter of a single injection hole is 0.2mm-2mm, and 8-20 injection holes are arranged on the inner wall of each second mixing channel. The distance between the injection hole and the injection surface is 10mm-50mm.

10. The gas-liquid phase mixing coaxial staged micro-mixing array nozzle burner according to any one of claims 1-9, characterized in that, The spray surface is a plane; Multiple nozzle units are arranged in one or more circles, either in a circular, rectangular, or fan shape.

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