Discrete hydrogen fuel nozzle structure with anti-oscillation measure
By designing a discrete hydrogen fuel nozzle structure with anti-oscillation measures, high-speed blending of hydrogen fuel and air and small-scale flame formation are achieved, which solves the problems of poor combustion stability and high NOx emissions of hydrogen fuel, improves combustion efficiency and reduces nitrogen oxidation Material emissions.
Patent Information
- Application Number
- CN202411116059.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-14
- Publication Date
- 2024-12-13
AI Technical Summary
Traditional combustion chambers have difficulties in achieving the stability of hydrogen combustion. Hydrogen fuel premixed combustion is prone to tempering and has poor stability. Although diffusion combustion avoids tempering, it is accompanied by high nitrogen oxide emissions, and the fuel-air ratio imbalance affects stability.
A discrete hydrogen fuel nozzle structure with anti-oscillation measures was designed. The high-speed blending of hydrogen fuel and air was achieved through the corresponding settings of the air injection port and the hydrogen fuel injection port on the nozzle plate, and the coordination of the angle and the purge hole. The small scale flame is formed to avoid backlash and oscillation, and reduce the residence time of nitrogen in the high-temperature zone through the purge holes and reduce NOx emissions.
It effectively improves the stability of hydrogen combustion, prevents tempering and combustion oscillation, reduces nitrogen oxide emissions, and improves combustion efficiency.
Smart Images
Figure CN119123423A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of burners, and in particular to a discrete hydrogen fuel nozzle structure with anti-oscillation measures. Background Art
[0002] Traditional combustion chambers have difficulties in achieving safe and stable hydrogen combustion, and it is difficult to ensure the smooth operation of hydrogen fuel combustion. Although the currently developed micro-mixed combustion technology can achieve hydrogen fuel combustion, it still has its own limitations. Premixed combustion will increase the risk of flashback due to the activity and high flame speed of hydrogen fuel. Although diffusion combustion can avoid the "flashback" problem of hydrogen fuel combustion, it will be accompanied by higher nitrogen oxide emissions, and the imbalance of the fuel-air ratio may have a negative impact on the stability of combustion. Summary of the invention
[0003] The present invention provides a discrete hydrogen fuel nozzle structure with anti-oscillation measures, which is used to solve the defects of hydrogen fuel premixed combustion in the prior art that it is easy to backfire and has poor stability.
[0004] The present invention provides a discrete hydrogen fuel nozzle structure with anti-oscillation measures, comprising: a nozzle plate, wherein the nozzle plate is provided with air injection ports along a first direction; A hydrogen fuel nozzle is arranged on the nozzle plate, wherein the hydrogen fuel nozzle is provided with a hydrogen fuel injection port along a second direction, the hydrogen fuel injection port corresponds to the air injection port, and an angle exists between the first direction and the second direction; a first fuel channel, one end of which is connected to the nozzle plate, and the first fuel channel is in communication with the air injection port; a second fuel channel, one end of which is connected to the hydrogen fuel nozzle; A plurality of purge holes are provided, and the plurality of purge holes are arranged on the nozzle plate along a first direction.
[0005] According to the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention, a plurality of air injection ports are provided, and the plurality of air injection ports are evenly distributed on the nozzle plate along the circumferential direction and surround the hydrogen fuel nozzle.
[0006] According to the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention, a plurality of hydrogen fuel injection ports are provided, and the plurality of hydrogen fuel injection ports are evenly distributed circumferentially on the outside of the hydrogen fuel nozzle, and the number of the hydrogen fuel injection ports is the same as that of the air injection ports and their positions correspond one to one.
[0007] According to the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention, the range of the angle a between the first direction and the second direction is 45°<a≤90°.
[0008] According to the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention, the second fuel channel is arranged in the first fuel channel.
[0009] According to the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention, the purge hole is a circular hole, and the aperture of the purge hole is 0.5-1.2 mm.
[0010] According to the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention, the relationship between the number B of the purge holes and the total area S of the air injection ports is 0.22S≤B≤0.45S.
[0011] According to the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention, the plurality of hydrogen fuel injection ports are evenly distributed around the outer peripheral side of the hydrogen fuel nozzle.
[0012] According to the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention, the first fuel channel is a cubic structure.
[0013] The discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention also includes a flame tube, the inner cavity of the flame tube forms a combustion chamber, the flame tube is axially connected to the first fuel channel, the first fuel channel is connected to the combustion chamber through a plurality of the air injection ports, and the second fuel channel is connected to the combustion chamber through a plurality of the hydrogen fuel injection ports.
[0014] The present invention provides a discrete hydrogen fuel nozzle structure with anti-oscillation measures, comprising: a nozzle plate, a hydrogen fuel nozzle, a first fuel channel, a second fuel channel and a purge hole, wherein mainstream air is ejected from the air injection port along a first direction via the first fuel channel, and hydrogen fuel is ejected from the hydrogen fuel injection port at a high speed along a second direction via the second fuel channel. Since the hydrogen fuel injection port corresponds to the air injection port and there is an angle between them, the hydrogen fuel injection port can be mixed with the air and burned to form a discrete flame of a microscopic scale. Through the provided purge hole, a small portion of the remaining air is ejected from the purge hole to achieve mixing and purging of residual hydrogen on the outer end face of the nozzle plate, thereby preventing a portion of hydrogen with a slower speed from staying on the end face to generate a reflow zone to cause thermoacoustic instability, thereby improving combustion stability, effectively preventing flashback and combustion oscillation, and also shortening the residence time of nitrogen in the high temperature zone due to the small scale of the reaction area, thereby achieving a reduction in NOx emissions. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0016] Figure 1 It is a structural schematic diagram of a discrete hydrogen fuel nozzle structure with anti-oscillation measures provided in an embodiment of the present invention.
[0017] Figure 2 It is a cross-sectional view of a discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by an embodiment of the present invention.
[0018] Figure 3 It is a top view of a structural schematic diagram of a discrete hydrogen fuel nozzle structure with anti-oscillation measures provided in an embodiment of the present invention.
[0019] Reference numerals: 1. Nozzle plate; 2. Hydrogen fuel nozzle; 3. First fuel channel; 4. Second fuel channel; 5. Air injection port; 6. Hydrogen fuel injection port; 7. Purge hole. DETAILED DESCRIPTION
[0020] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0021] Combine the following Figure 1-Figure 3 A discrete hydrogen fuel nozzle structure with anti-oscillation measures of the present invention is described.
[0022] The embodiment of the present invention provides a discrete hydrogen fuel nozzle structure with anti-oscillation measures, such as Figure 1-Figure 2 As shown, it includes: a nozzle plate 1, a hydrogen fuel nozzle 2, a first fuel channel 3, a second fuel channel 4 and a purge hole 7.
[0023] Among them, the nozzle plate 1 is provided with an air injection port 5 along the first direction, the hydrogen fuel nozzle 2 is arranged on the nozzle plate 1, and the hydrogen fuel nozzle 2 is provided with a hydrogen fuel injection port 6 along the second direction, the hydrogen fuel injection port 6 corresponds to the air injection port 5, and there is an angle between the first direction and the second direction; one end of the first fuel channel 3 is connected to the nozzle plate 1, and the first fuel channel 3 is connected to the air injection port 5; one end of the second fuel channel 4 is connected to the hydrogen fuel nozzle 2; a plurality of purge holes 7 are provided, and a plurality of purge holes 7 are arranged on the nozzle plate 1 along the first direction, wherein the first direction is the same as the axial direction of the first fuel channel 3, that is, perpendicular to the direction of the nozzle plate 1, and the second direction is parallel to the surface of the nozzle plate 1.
[0024] With such arrangement, the discrete hydrogen fuel nozzle structure with anti-oscillation measures provided by the present invention has the following steps: mainstream air is ejected from the air injection port 5 along a first direction via the first fuel channel 3, and hydrogen fuel is ejected from the hydrogen fuel injection port 6 along a second direction at high speed via the second fuel channel 4. Since the hydrogen fuel injection port 6 corresponds to the air injection port 5 and there is an angle between them, the hydrogen fuel injection port can be mixed with the air and burned to form a discrete flame of microscopic scale. The remaining small part of the air is ejected from the purge hole 7 through the provided purge hole 7, so as to achieve the mixing and purging of the residual hydrogen on the outer end face of the nozzle plate 1, and avoid the slower part of the hydrogen staying on the end face to generate a reflow zone to cause thermoacoustic instability, thereby improving the combustion stability, effectively preventing flashback and combustion oscillation, and also shortening the residence time of nitrogen in the high temperature zone due to the small scale of the reaction area, thereby achieving the reduction of NOx emissions.
[0025] like Figure 3 As shown, optionally, the air injection port 5 is circular, or may be other polygonal shapes such as a triangle or a rectangle, and of course may also be irregular shapes such as a cloud shape.
[0026] In this embodiment, a plurality of air injection ports 5 are provided, and the plurality of air injection ports 5 are evenly distributed on the nozzle plate 1 along the circumferential direction and surround the hydrogen fuel nozzle 2; a plurality of hydrogen fuel injection ports 6 are provided, and the plurality of hydrogen fuel injection ports 6 are evenly distributed on the outside of the hydrogen fuel nozzle 2 along the circumferential direction, and the number of hydrogen fuel injection ports 6 is the same as that of the air injection ports 5 and their positions correspond one to one.
[0027] With such an arrangement, the number of air injection ports 5 and hydrogen fuel injection ports 6 is equal, which helps to improve the fuel-air mixing effect. The hydrogen fuel is ejected laterally from the hydrogen fuel injection ports 6 at high speed and mixed strongly with the air, burning while mixing to form a plurality of discrete flames of microscopic scale. The remaining small portion of air is ejected from the purge holes 7 to achieve mixing and purging of the residual hydrogen on the outer end face of the nozzle plate 1, preventing the hydrogen with a low axial velocity from agglomerating to form a reflux zone, thereby suppressing oscillation, effectively improving the combustion efficiency, avoiding flashback and ablation, and reducing the thermoacoustic instability of hydrogen fuel combustion. In addition, the residence time of nitrogen in the high temperature zone is shortened due to the small scale of the reaction zone, thereby achieving a reduction in NOx emissions.
[0028] In some embodiments, the angle a between the first direction and the second direction is in the range of 45°<a≤90°. Preferably, the angle a is 90°, so that the hydrogen fuel is strongly mixed with the air in the form of a lateral jet after being ejected from the hydrogen fuel injection port 6 .
[0029] In this embodiment, the first fuel channel 3 is a cubic structure, the second fuel channel 4 is arranged in the first fuel channel 3, the hydrogen fuel nozzle 2 is arranged at the center of the nozzle plate 1, and multiple air injection ports 5 are evenly distributed around the hydrogen fuel nozzle 2 along the circumferential direction; wherein, the hydrogen fuel nozzle 2 can be a cylindrical structure, and the hydrogen fuel nozzle 2 is protruded on the nozzle plate 1, so that the multiple hydrogen fuel injection ports 6 are evenly distributed on the outer peripheral side of the hydrogen fuel nozzle 2 along the circumferential direction and can be sprayed laterally.
[0030] Of course, the hydrogen fuel nozzle 2 may also be other polygonal columnar structures, such as quadrangular prisms, hexagonal prisms, etc., and a plurality of hydrogen fuel injection ports 6 are evenly distributed around the outer circumference of the hydrogen fuel nozzle 2 .
[0031] In some embodiments, the purge holes 7 are circular holes evenly distributed around the air injection port 5. The number of purge holes at the end corners can be appropriately increased or the aperture can be reduced to facilitate better uniform distribution on the surface of the nozzle plate 1. The aperture of the purge holes 7 is 0.5~1.2mm.
[0032] Optionally, the relationship between the number B of the purge holes 7 and the total area S of the air injection ports 5 is 0.22S≤B≤0.45S.
[0033] Furthermore, it also includes a flame tube, the inner cavity of the flame tube forms a combustion chamber, the flame tube is axially connected to the first fuel channel 3, the first fuel channel 3 is connected to the combustion chamber through multiple air injection ports 5, and the second fuel channel 4 is connected to the combustion chamber through multiple hydrogen fuel injection ports 6.
[0034] With such arrangement, air flows into six circumferentially uniformly distributed air injection ports 5 at high speed through the first fuel channel 3, and hydrogen fuel is ejected laterally from six hydrogen fuel injection ports 6 at high speed through the second fuel channel 4, where it is strongly mixed with the air and burns while mixing, forming a plurality of discrete flames of microscopic scale, thereby improving combustion stability, effectively preventing flashback and combustion oscillation, and the residence time of nitrogen in the high temperature zone is shortened due to the small scale of the reaction zone, thereby achieving a reduction in NOx emissions.
[0035] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.
[0036] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "mode", "specific mode", or "some modes" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or mode are included in at least one embodiment or mode of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or mode. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or modes in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or modes described in this specification and the features of the different embodiments or modes, without contradiction.
[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A discrete hydrogen fuel nozzle structure with anti-oscillation measures, It is characterized in that include: A nozzle plate (1), wherein the nozzle plate (1) is provided with air injection ports (5) along a first direction; A hydrogen fuel nozzle (2) is arranged on the nozzle plate (1), the hydrogen fuel nozzle (2) is provided with a hydrogen fuel injection port (6) along a second direction, the hydrogen fuel injection port (6) corresponds to the air injection port (5), and an angle exists between the first direction and the second direction; A first fuel channel (3), one end of the first fuel channel (3) being connected to the nozzle plate (1), and the first fuel channel (3) being in communication with the air injection port (5); a second fuel channel (4), one end of the second fuel channel (4) being connected to the hydrogen fuel nozzle (2); A plurality of purge holes (7) are provided, and the plurality of purge holes (7) are arranged on the nozzle plate (1) along a first direction.
2. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 1, It is characterized in that A plurality of the air injection ports (5) are provided, and the plurality of air injection ports (5) are evenly distributed on the nozzle plate (1) along the circumferential direction and surround the hydrogen fuel nozzle (2).
3. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 2, It is characterized in that A plurality of hydrogen fuel injection ports (6) are provided, and the plurality of hydrogen fuel injection ports (6) are evenly distributed along the circumferential direction on the outside of the hydrogen fuel nozzle (2), and the number of the hydrogen fuel injection ports (6) and the air injection ports (5) are the same and their positions correspond one to one.
4. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 1, It is characterized in that The range of the angle a between the first direction and the second direction is 45°<a≤90°.
5. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 1, It is characterized in that The second fuel channel (4) is arranged in the first fuel channel (3).
6. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 1, It is characterized in that The purge hole (7) is a circular hole, and the diameter of the purge hole (7) is 0.5-1.2 mm.
7. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 1, It is characterized in that The relationship between the number B of the purge holes (7) and the total area S of the air injection ports (5) is 0.22S≤B≤0.45S.
8. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 1, It is characterized in that The plurality of hydrogen fuel injection ports (6) are evenly distributed around the outer circumference of the hydrogen fuel nozzle (2).
9. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 1, It is characterized in that The first fuel channel (3) is a cubic structure.
10. The discrete hydrogen fuel nozzle structure with anti-oscillation measures according to claim 1, It is characterized in that It also includes a flame tube, the inner cavity of which forms a combustion chamber, the flame tube is axially connected to the first fuel channel (3), the first fuel channel (3) is connected to the combustion chamber through a plurality of air injection ports (5), and the second fuel channel (4) is connected to the combustion chamber through a plurality of hydrogen fuel injection ports (6).