Laminar premixed flat flame burner and its operation method

Abstract

This invention discloses a laminar flow premixed flat flame burner and its operating method. The laminar flow premixed flat flame burner includes: a circular tube shell; multiple gas tubes, which are axially parallel and oriented along the axial direction of the circular tube shell. Each gas tube includes multiple inner tubes and multiple outer tubes. The inner tubes are connected to a premixed fuel gas source, and the outer tubes are connected to a protective gas source. The outer tubes are closely arranged radially inside the circular tube shell, and the inner tubes are closely arranged radially inside the outer tubes. Each gas tube is tangent to at least three other gas tubes, allowing the multiple gas tubes to be tightly disposed within the circular tube shell by friction. The upper ends of the multiple gas tubes are flush with the upper end of the circular tube shell; and a cooling tube tightly coiled around the outer circumference of the circular tube shell. The laminar flow premixed flat flame burner according to this invention has advantages such as stable flame, flat flame, uniform flame temperature, simple structure, convenient manufacturing, and low cost.

Description

Technical Field

[0001] This invention relates to the field of burner manufacturing technology, and more specifically, to a laminar flow premixed flat flame burner and a method for operating the laminar flow premixed flat flame burner. Background Technology

[0002] Combustion is a flow phenomenon accompanied by chemical reactions and is an essential energy conversion pathway in human production and daily life, permeating almost all areas of industrial production. Understanding the mechanisms behind combustion is crucial for improving combustion efficiency, reducing environmental pollution, and designing specialized combustion processes. However, the combustion process is extremely complex, involving chemical reactions, heat and mass transfer, and fluid motion, making its mechanism research a major challenge. In the field of combustion research, it is often necessary to generate simplified, specialized flames to facilitate research. Laminar premixed planar flames are one such example, with wide applications including serving as standard flame calibration sources for laser combustion diagnostic technology, microgravity flame research, and studies on soot formation mechanisms.

[0003] Flat flame burners in related technologies can produce stable planar flames, but their manufacturing process is complex, expensive, and difficult to produce. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a laminar flow premixed flat flame burner, which has the advantages of stable flame, flat flame, uniform flame temperature, simple structure, convenient manufacturing, and low cost.

[0005] The present invention also proposes an operating method for the laminar premixed flat flame burner.

[0006] To achieve the above objectives, according to an embodiment of the first aspect of the present invention, a laminar flow premixed flat flame burner is provided, the laminar flow premixed flat flame burner comprising: a circular tube shell; a plurality of gas tubes, the plurality of gas tubes being axially parallel and oriented along the axial direction of the circular tube shell, the plurality of gas tubes including a plurality of inner tubes and a plurality of outer tubes, the inner tubes being connected to a premixed fuel gas source, the outer tubes being connected to a protective gas source, the plurality of outer tubes being closely arranged radially inside the circular tube shell, the plurality of inner tubes being closely arranged radially inside the plurality of outer tubes, each gas tube being tangent to at least three gas tubes such that the plurality of gas tubes are tightly disposed within the circular tube shell by friction, the upper ends of the plurality of gas tubes being flush with the upper end of the circular tube shell; and a cooling tube, the cooling tube being tightly coiled around the outer circumferential surface of the circular tube shell, the cooling tube being connected to a circulating coolant source.

[0007] The laminar premixed flat flame burner according to embodiments of the present invention has advantages such as stable flame, flat flame, uniform flame temperature, simple structure, convenient manufacturing, and low cost.

[0008] In addition, the laminar premixed flat flame burner according to the above embodiments of the present invention may also have the following additional technical features:

[0009] According to one embodiment of the present invention, a plurality of the outer tubes are arranged in 1-3 layers in the radial direction of the circular tube shell, each layer comprising a plurality of the outer tubes arranged closely in the circumferential direction of the circular tube shell.

[0010] According to one embodiment of the present invention, the outer diameter of the inner tube is less than or equal to 1.3 mm.

[0011] According to one embodiment of the present invention, both the gas pipe and the circular pipe shell are made of high-temperature resistant materials.

[0012] According to one embodiment of the present invention, the outer diameter of the circular tube shell is 31-41 mm and the inner diameter is 27-37 mm.

[0013] According to one embodiment of the present invention, the axial lengths of the gas tube and the circular tube housing are equal and are 10-20 mm.

[0014] According to one embodiment of the present invention, the outer surface of the cooling pipe is coated with thermally conductive mud.

[0015] According to one embodiment of the present invention, the cooling pipe is disposed at the lower part of the circular tube housing.

[0016] According to one embodiment of the present invention, the protective gas source is a nitrogen source, a helium source, or an argon source.

[0017] According to an embodiment of the second aspect of the present invention, a method for operating a laminar premixed flat flame burner according to an embodiment of the first aspect of the present invention is provided, comprising the following steps:

[0018] Premixed gas is introduced into the inner tube;

[0019] Ignite the premixed gas;

[0020] A protective gas is introduced into the outer tube;

[0021] Circulating coolant is introduced into the cooling pipe to begin the experiment;

[0022] After the experiment, the premixed gas, the protective gas, and the circulating coolant were sequentially shut off.

[0023] The operation method of the laminar flow premixed flat flame burner according to the embodiments of the present invention has the advantages of flame stability, flame flatness, and uniform flame temperature by utilizing the laminar flow premixed flat flame burner described in the first aspect of the present invention.

[0024] 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

[0025] 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:

[0026] Figure 1 This is a schematic diagram of the structure of a laminar flow premixed flat flame burner according to an embodiment of the present invention.

[0027] Figure 2 This is a flowchart of the operation method of a laminar premixed flat flame burner according to an embodiment of the present invention.

[0028] Reference numerals: 1. Laminar flow premixed flat flame burner; 10. Circular tube shell; 21. Inner tube; 22. Outer tube; 30. Cooling tube. Detailed Implementation

[0029] 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.

[0030] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "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.

[0031] 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 according to the specific circumstances.

[0032] The laminar premixed flat flame burner 1 according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0033] like Figure 1 and Figure 2 As shown, the laminar flow premixed flat flame burner 1 according to an embodiment of the present invention includes a circular tube shell 10, a plurality of gas pipes and a cooling pipe 30.

[0034] Multiple gas pipes are axially parallel and oriented along the axial direction of the circular tube housing 10. Each gas pipe includes multiple inner tubes 21 and multiple outer tubes 22. The inner tubes 22 are connected to a premixed fuel gas source, and the outer tubes 21 are connected to a protective gas source. The outer tubes 22 are closely arranged radially inside the circular tube housing 10. In the radial direction of the circular tube housing 10, the inner tubes 21 are closely arranged inside the outer tubes 22. Each gas pipe is tangent to at least three other gas pipes, allowing the multiple gas pipes to be tightly disposed within the circular tube housing 10 by friction. The upper ends of the multiple gas pipes are flush with the upper end of the circular tube housing 10 (the vertical direction is shown by the arrows in the figure and is for illustrative purposes only, not a limitation on the actual arrangement direction). A cooling pipe 30 is tightly coiled around the outer circumferential surface of the circular tube housing 10 and is connected to a circulating coolant source.

[0035] It should be understood here that the premixed gas refers to the mixed gas after the gas and the combustion-supporting gas have been mixed in advance.

[0036] According to an embodiment of the present invention, the laminar premixed flat flame burner 1 can form an inner honeycomb gas chamber by providing a plurality of inner tubes 21. When the laminar premixed flat flame burner 1 is working, premixed gas is passed through and ignited to generate a premixed planar flame.

[0037] Furthermore, by setting multiple outer tubes 22, the outer honeycomb gas chamber is formed by the closely arranged multiple outer tubes 22. When the laminar flow premixed flat flame burner 1 is working, a protective gas is introduced to form a protective gas shield around the planar flame generated by the inner tube 21, which avoids air convection causing instability of the planar flame, thereby ensuring that the generated planar flame is flat and stable, with uniform temperature, and is not easily affected by the experimental external environment.

[0038] In other words, the laminar premixed flat flame burner 1 according to the embodiment of the present invention can achieve a flat, stable, and uniformly heated planar flame by relying only on the closely arranged inner tube 21 and outer tube 22. Compared with the flat flame burners in related technologies that use expensive and complex structures such as high-temperature resistant porous ceramics, the structure is simpler, the manufacturing difficulty is lower, and the manufacturing cost is lower.

[0039] Furthermore, by making each gas tube tangent to at least three gas tubes so that multiple gas tubes are arranged in the circular tube housing 10 by friction, on the one hand, the number of inner tubes 21 and outer tubes 22 can be guaranteed to form a honeycomb-shaped gas chamber structure. On the other hand, the inner tubes 21 and outer tubes 22 are fixed by radial friction, avoiding the difficult drilling and welding process. This further facilitates the production and manufacturing of the laminar flow premixed flat flame burner 1, further reduces the manufacturing cost of the laminar flow premixed flat flame burner 1, and also makes it easier to disassemble and maintain the laminar flow premixed flat flame burner 1.

[0040] In addition, by setting up a cooling pipe 30, circulating coolant is supplied when the laminar premixed flat flame burner 1 is working. The cooling pipe 30 and the circulating coolant can be used to cool the round tube shell 10 to avoid overheating failure of the laminar premixed flat flame burner 1.

[0041] Therefore, the laminar premixed flat flame burner 1 according to the embodiments of the present invention has the advantages of stable flame, flat flame, uniform fire temperature, simple structure, convenient manufacturing and low cost.

[0042] The laminar premixed flat flame burner 1 according to a specific embodiment of the present invention is described below with reference to the accompanying drawings.

[0043] In some specific embodiments of the present invention, such as Figure 1 and Figure 2 As shown, the laminar flow premixed flat flame burner 1 according to an embodiment of the present invention includes a circular tube shell 10, a plurality of gas pipes and a cooling pipe 30.

[0044] Specifically, such as Figure 1 As shown, multiple outer tubes 22 are arranged in 1-3 layers radially along the circular tube shell 10, each layer comprising multiple outer tubes 22 closely arranged circumferentially along the circular tube shell 10. This allows for a reduction in the thickness of the protective gas layer while ensuring its effectiveness in generating the protective gas layer, thereby guaranteeing the area of ​​the planar flame.

[0045] Specifically, multiple gas tubes can be arranged as closely as possible within the circular tube housing 10. Those skilled in the art can determine the number and arrangement of the gas tubes based on the outer diameter of the gas tubes and the inner diameter of the circular tube housing 10.

[0046] Optionally, the outer diameter of the inner tube 21 is less than or equal to 1.3 mm. Preferably, the inner diameter of the inner tube 21 is 0.8 mm and the outer diameter is 1.0 mm. Specifically, the premixed gas can be a mixture of ethylene and a combustion-supporting gas. This ensures that the outer diameter of the inner tube 21 is smaller than the flameout distance of the gas, thus preventing backfire.

[0047] Specifically, the outer tube 22 can have the same diameter as the inner tube 21 to facilitate the processing and manufacturing of the gas tube.

[0048] The outer tube 22 may also have a different diameter than the inner tube 21. It can be increased or decreased according to actual needs to increase the friction between the gas tubes, making the structure of the laminar premixed flat flame burner 1 more stable and preventing the gas tubes from falling off.

[0049] Advantageously, both the gas pipe and the cylindrical shell 10 are made of high-temperature resistant materials. Specifically, the inner tube 21, the outer tube 22, and the cylindrical shell 10 can be made of aerospace alloy or 304 stainless steel. This prevents the gas pipe and the cylindrical shell 10 from being damaged by high temperatures during the operation of the laminar premixed flat flame burner 1.

[0050] Furthermore, the outer diameter of the circular tube shell 10 is 31-41 mm and the inner diameter is 27-37 mm. Preferably, the outer diameter is 36 mm and the inner diameter is 32 mm. This ensures the area of ​​the planar flame, increases the number of gas tubes, and facilitates the formation of honeycomb-shaped gas chambers.

[0051] Furthermore, the axial lengths of the gas pipe and the circular tube shell 10 are equal and range from 10 to 20 mm. Preferably, the axial lengths are both 15 mm. This allows the laminar premixed flat flame burner 1 to have reasonable axial dimensions, facilitating the formation of a planar flame and simplifying the processing and manufacturing of the laminar premixed flat flame burner 1.

[0052] Advantageously, the outer surface of the cooling pipe 30 is coated with thermally conductive putty. This can improve the thermal conductivity between the cooling pipe 30 and the cylindrical shell 10, and improve the cooling effect of the cooling pipe 30 on the cylindrical shell 10.

[0053] More advantageously, such as Figure 1 As shown, the cooling pipe 30 is located at the lower part of the circular tube housing 10. This prevents the cooling pipe 30 from interfering with the formation of the planar flame and from affecting the experimental results of the planar flame.

[0054] Optionally, the protective gas source is a nitrogen source, a helium source, or an argon source. This ensures the stability of the protective gas shield layer against planar flames.

[0055] The circulating coolant source can be a circulating cooling water source.

[0056] Specifically, the flow rate of the protective gas is kept consistent with the flow rate of the premixed gas to avoid pressure differentials that could lead to flame instability.

[0057] The cooling pipe 30 can be coiled multiple times on the outer circumferential surface of the circular tube housing 10 to improve the cooling effect on the circular tube housing 10.

[0058] The following describes the operation method of the laminar premixed flat flame burner 1 according to the above embodiment of the present invention, including the following steps:

[0059] Premixed gas is introduced into the inner tube 21;

[0060] Ignite the premixed gas;

[0061] Introduce protective gas into the outer tube 22;

[0062] Circulating coolant is introduced into cooling pipe 30 to begin the experiment;

[0063] After the experiment, the premixed gas, the protective gas, and the circulating coolant were sequentially shut off.

[0064] The operation method of the laminar flow premixed flat flame burner according to the embodiments of the present invention has the advantages of stable flame, flat flame, and uniform flame temperature by utilizing the laminar flow premixed flat flame burner 1 according to the above embodiments of the present invention.

[0065] Other configurations and operations of the laminar premixed flat flame burner 1 according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0066] 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.

[0067] 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 laminar premixed flat flame burner, characterized in that, include: Circular tube shell; Multiple gas tubes are provided, all axially parallel and oriented along the axial direction of the circular tube housing. Each gas tube includes multiple inner tubes and multiple outer tubes. The inner tubes are connected to a premixed gas source, and the outer tubes are connected to a protective gas source. The outer tubes are closely arranged radially inside the circular tube housing. In the radial direction of the circular tube housing, the inner tubes are closely arranged inside the outer tubes. Each gas tube is tangent to at least three other gas tubes so that the gas tubes are tightly disposed within the circular tube housing by friction. The upper ends of the gas tubes are flush with the upper end of the circular tube housing. A cooling pipe is tightly coiled around the outer circumference of the circular tube shell and is connected to a circulating coolant source. The outer surface of the cooling pipe is coated with thermally conductive mud, and the cooling pipe is located at the lower part of the circular tube shell. The outer diameter of the circular tube shell is 31-41 mm and the inner diameter is 27-37 mm. The axial length of the gas pipe and the circular tube shell are equal and are 10-20 mm.

2. The laminar premixed flat flame burner according to claim 1, characterized in that, The plurality of outer tubes are arranged in 1-3 layers in the radial direction of the circular tube shell, each layer comprising a plurality of outer tubes closely arranged in the circumferential direction of the circular tube shell.

3. The laminar premixed flat flame burner according to claim 1, characterized in that, The outer diameter of the inner tube is less than or equal to 1.3 mm.

4. The laminar premixed flat flame burner according to claim 1, characterized in that, Both the gas pipe and the cylindrical shell are made of high-temperature resistant materials.

5. The laminar premixed flat flame burner according to claim 1, characterized in that, The protective gas source is a nitrogen source, a helium source, or an argon source.

6. A method of operating a laminar premixed flat flame burner according to any one of claims 1-5, characterized in that, Includes the following steps: Premixed gas is introduced into the inner tube; Ignite the premixed gas; A protective gas is introduced into the outer tube; Circulating coolant is introduced into the cooling pipe to begin the experiment; After the experiment, the premixed gas, the protective gas, and the circulating coolant were sequentially shut off.

Images