gas burner

Abstract

To provide a porous ceramic gas burner capable of suppressing pressure loss. [Solution] The gas burner comprises a burner body having an inlet end for introducing flammable gas, a nozzle for ejecting flammable gas, an overall flow path configured between the inlet end and the nozzle for circulating the flammable gas, a flow path partition made of porous ceramic that divides the overall flow path into a plurality of flow paths along an axis from the inlet end to the nozzle and allows the flammable gas to pass through, a sealing portion provided at different positions in the flow direction of the flammable gas between adjacent flow paths, and a flame-holding portion provided at the nozzle for holding the flame, and a mounting member for attaching the burner body to the flow path of the flammable gas.

Description

Technical Field

[0001] The present disclosure relates to a gas burner.

Background Art

[0002] Conventionally, as a burner for burning combustible gas, a burner having a flashback prevention function has been proposed. (See Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, a flame barrier using porous ceramics is disposed adjacent to the upstream side of the combustion chamber to prevent flashback. However, there is a limit to reducing the diameter of the holes formed in the flame barrier, and the pressure loss also increases.

[0005] The present disclosure has been made in consideration of the above facts, and an object thereof is to provide a gas burner having a flashback prevention function while suppressing pressure loss.

Means for Solving the Problems

[0006] A gas burner according to the first embodiment comprises a burner body having an inlet end for introducing flammable gas, a nozzle for ejecting flammable gas, an overall flow path configured between the inlet end and the nozzle for circulating the flammable gas, a flow path partition made of porous ceramics that divides the overall flow path into a plurality of unit flow paths along an axis from the inlet end to the nozzle and allows the flammable gas to pass through, a sealing portion provided at different positions in the flow direction of the flammable gas between adjacent unit flow paths, and a flame-holding portion formed at the nozzle for holding the flame, and a mounting member for attaching the burner body to the flow path of the flammable gas.

[0007] In the first embodiment of the gas burner, flammable gas flowing in from the inlet end of a unit flow path is blocked by a sealing section and moves through the flow path partition to an adjacent unit flow path. If the sealing section of the destination unit flow path is on the inlet side, the flammable gas flows out from the outlet of that unit flow path. If the sealing section of the destination unit flow path is at the outlet, the gas moves further through the flow path partition to a unit flow path with an open outlet. Combustion then takes place in the flame-holding section formed at the outlet.

[0008] According to the first embodiment of the gas burner, since the flow channel partitions are formed from porous ceramics, it can be manufactured relatively easily. Furthermore, by allowing the flammable gas to flow through the flow channel partitions, the area of ​​the flow channel partitions through which the flammable gas permeates can be made larger than the cross-sectional area of ​​the unit flow channel into which the flammable gas flows, thereby reducing the pressure loss of the flammable gas. In addition, the sealing portion and the flow channel partitions prevent the flame from passing through, thus preventing flashback from the outlet side to the inlet side.

[0009] A gas burner of the second embodiment further comprises a heat transfer suppression unit provided between the outlet and the inlet end, which suppresses heat transfer from the flame holder to the inlet end, in addition to the gas burner of the first embodiment.

[0010] According to the gas burner of the second embodiment, the heat transfer suppression unit suppresses heat transfer from the flame holder to the inlet end, thereby suppressing high-temperature ignition upstream of the heat transfer suppression unit.

[0011] A third embodiment of the gas burner is configured such that, in the gas burner of the first embodiment, the sealing portion includes an inlet end sealing portion that seals the inlet end of a portion of the plurality of unit flow paths, and an outlet sealing portion that seals the remaining outlets of the plurality of unit flow paths.

[0012] According to the third embodiment of the gas burner, a sealing portion can be easily formed because it is formed at the inlet end or outlet.

[0013] The gas burner of the fourth embodiment is a flashback prevention device of the third embodiment, wherein the inlet end sealing portion and the outlet sealing portion are alternately formed in adjacent unit flow paths.

[0014] According to the gas burner of the fourth embodiment, the area of ​​the channel partition through which the flammable gas permeates can be increased in adjacent unit channels, and the flammable gas that flows in from one unit channel can be discharged from the adjacent unit channel, thereby further reducing the pressure loss of the flammable gas.

[0015] In the fifth embodiment of the gas burner, the plurality of unit flow paths have a polygonal cross-section.

[0016] According to the fifth embodiment of the gas burner, the flow channel partitions between adjacent unit flow channels can be made of a constant thickness, thereby reducing the pressure loss of the flammable gas.

[0017] A gas burner according to a sixth embodiment further comprises a check member positioned upstream of the burner body and preventing the burner body from moving upstream relative to the mounting member.

[0018] According to the sixth embodiment of the gas burner, even if an impact is applied to the burner body toward the upstream side, the check valve can prevent it from moving toward the upstream side.

Advantages of the Invention

[0019] According to the technology of the present disclosure, a gas burner having an anti-backfire function while suppressing pressure loss can be provided.

Brief Description of the Drawings

[0020] [Figure 1] (A) is a schematic view showing a state where the gas burner of the present embodiment is attached to a flow path of a combustible gas, and (B) is a perspective view of the gas burner. [Figure 2] (A) of the present embodiment is a partial configuration diagram on the upstream side of the gas burner, and (B) is a plan view of the gas burner as viewed from the upstream side. [Figure 3] It is a front view of the gas burner of the present embodiment. [Figure 4] It is a perspective view of the gas burner of the present embodiment. [Figure 5] It is a longitudinal sectional view of the gas burner of the present embodiment. [Figure 6] It is a longitudinal sectional view of a modified gas burner of the present embodiment. [Figure 7] It is a perspective view of another modified gas burner of the present embodiment. [Figure 8] It is a front view of another modified gas burner of the present embodiment. [Figure 9] It is a perspective view of another modified gas burner of the present embodiment. [Figure 10] It is a longitudinal sectional view of another modified gas burner of the present embodiment.

Modes for Carrying Out the Invention

[0021] Hereinafter, the gas burner according to the present disclosure will be described with reference to the drawings.

[0022] The gas burner 10 according to this disclosure is attached to the end of the combustible gas flow path 12, as shown in Figure 1(A). In the combustible gas flow path 12, the oxygen supply path 12A and the combustible gas supply path 12B merge on the upstream side, and a mixture of oxygen and combustible gas flows through it. Examples of combustible gases include hydrogen gas, methane gas, city gas, LP gas, and butane gas.

[0023] The gas burner 10 comprises a burner body 20 and a mounting member 22 for attaching the burner body 20 to the flammable gas flow path 12. The mounting member 22 is a hollow rectangular tube with a joining flange portion 22A at one end and an annular flame-holding portion 23 at the other end. The mounting member 22 is joined to the end of the flammable gas flow path 12 at the joining flange portion 22A. As shown in Figure 1(B), the annular flame-holding portion 23 is integrally molded to the other end of the mounting member 22. The burner body 20 is housed inside the mounting member 22.

[0024] Inside the mounting member 22, there is a check valve member 22B, which has an inner diameter smaller than the outer diameter of the burner body 20 (see Figures 2(A) and 2(B)). The check valve member 22B is located on the inlet end 20A side of the burner body 20 (described later), that is, upstream of the burner body 20. The check valve member 22B is welded to the mounting member 22.

[0025] As shown in Figures 3 and 4, the burner body 20 has an outer wall portion 24 that is a rectangular tube with a diameter slightly smaller than that of the mounting member 22. As shown in Figure 5, one end opening of the outer wall portion 24 (left side in Figure 5) becomes the inlet end 20A, and the other end opening of the outer wall portion 24 (right side in Figure 5) becomes the nozzle 20B. The axis (tubular axis) of the outer wall portion 24 from the inlet end 20A to the nozzle 20B is defined as the axial direction S.

[0026] Multiple unit channels 26A and 26B are formed inside the outer wall portion 24. The multiple unit channels 26A and 26B are divided into multiple rows alternately in the vertical and horizontal directions by channel partition walls 28, and have a rectangular cross-section. The multiple unit channels 26A and 26B have the same cross-sectional shape. The multiple unit channels 26A and 26B form an overall channel 26 inside the burner body 20, extending from one end of the cylinder to the other. The burner body 20 is arranged such that the direction of the openings of the multiple unit channels 26A and 26B coincides with the direction of the openings of the mounting member 22. The thickness T1 of the channel partition walls 28 is formed to be thinner than the horizontal length L1 and vertical length L2 of the cross-section of the unit channels 26A and 26B.

[0027] The thickness T1 of the flow channel partition wall 28 is preferably formed to an average of 0.2 mm to 0.8 mm. If it is thinner than 0.2 mm, the partition wall strength will not be sufficient and it will be prone to damage, and if it is thicker than 0.8 mm, the pressure loss will tend to be high. The lateral length L1 and vertical length L2 of the cross-section of the unit flow channels 26A and 26B are preferably formed to an average of 50 mm to 150 mm. If it is shorter than 50 mm, the gas passage area will be small and the pressure loss will tend to be high, and if it is longer than 150 mm, the device will be large and difficult to handle.

[0028] The channel partition wall 28 is formed of porous ceramics. The outer wall portion 24 is also formed of the same porous ceramics, and the outer wall portion 24 and the channel partition wall 28 are integrally molded. The porous ceramics forming the channel partition wall 28 preferably consists mainly of silicon carbide, cordierite, mullite, and alumina, with a porosity of 30-50% and an average pore diameter of 5-20 μm. If the porosity is less than 30%, the pressure loss tends to be high, and if it is greater than 50%, the strength of the partition wall tends to be insufficient. If the average pore diameter is less than 5 μm, the pressure loss tends to be high, and if it is greater than 20 μm, it tends to cause insufficient strength or the initiation of cracks.

[0029] The unit flow path 26A has an inlet end sealing portion 30A that seals the inlet end 20A side. The inlet end sealing portion 30A prevents the unit flow path 26A from passing through from the inlet end 20A to the nozzle 20B. The unit flow path 26B has an outlet sealing portion 30B that seals the nozzle 20B side. The outlet sealing portion 30B prevents the unit flow path 26B from passing through from the inlet end 20A to the nozzle 20B.

[0030] The inlet end sealing portion 30A and the nozzle sealing portion 30B are formed of porous ceramics.

[0031] It is preferable that the porous ceramics forming the inlet end sealing portion 30A and the outlet sealing portion 30B be made of the same material as the porous ceramics forming the flow channel partition wall 28. By using the same material, the coefficient of thermal expansion will be the same, thus preventing cracks from starting during heating.

[0032] The axial length S L of the inlet end sealing portion 30A and the outlet sealing portion 30B is longer than the thickness T1 of the flow path partition wall 28. It is preferable that the length L be formed to be about 2 mm to 10 mm. If it is shorter than 2 mm, there is a possibility of sealing failure, and if it is longer than 10 mm, the effective area of ​​the partition wall becomes small, which tends to increase pressure loss. In addition, the area of ​​the flow path partition wall 28 along the axial direction S of adjacent unit flow paths 26A and 26B is set to be larger than the sum of the cross-sectional areas of unit flow paths 26A and 26B.

[0033] An elastically deformable expandable member 40 is positioned across the entire surface between the inner circumferential surface of the mounting member 22 and the outer circumferential surface of the burner body 20 (see Figure 3). By contracting the expandable member 40 and positioning the burner body 20 inside the mounting member 22, the burner body 20 can be press-fitted into the mounting member 22. The expandable member 40 also deforms in accordance with the expansion and contraction of the burner body 20 and the mounting member 22, absorbing such expansion and contraction. As the expandable member 40, a fiber mat material mainly composed of alumina or silica can be used.

[0034] A flame-holding section 21 is formed at the nozzle 20B. The flame-holding section 21 is composed of the end face of the nozzle 20B of the burner body 20 and the annular flame-holding section 23 of the mounting member 22. An ignition section 25 is provided near the flame-holding section 21.

[0035] Next, the effects and advantages of the gas burner 10 of this embodiment will be described.

[0036] In this embodiment, since an inlet end sealing portion 30A and an outlet sealing portion 30B are formed in adjacent unit flow paths 26A and 26B, respectively, flammable gas flowing in from one unit flow path 26B can be discharged downstream from the adjacent unit flow path 26A. The flammable gas flowing through the flammable gas flow path 12 is supplied from the inlet end 20A side of the burner body 20 and flows into the unit flow path 26B. The incoming flammable gas permeates through the flow path partition wall 28 and moves to the adjacent unit flow path 26A, and is discharged from the outlet 20B side of the unit flow path 26A. Since the area of ​​the flow path partition wall 28 is set to be larger than the sum of the cross-sectional areas of the unit flow paths 26A and 26B, pressure loss can be reduced.

[0037] When the ignition unit 25 ignites the flammable gas sent from the nozzle 20B side, the flammable gas burns and a flame is generated in the flame holder 21. Even if the flame were to travel backward from the flame holder 21, the unit flow paths 26A and 26B of the burner body 20 are designed so that they do not penetrate from the inlet end 20A to the nozzle 20B. The inlet end sealing section 30A, the nozzle sealing section 30B, and the flow path partition wall 28 prevent the backfire from penetrating.

[0038] Furthermore, in this embodiment, since a check valve member 22B is provided, even if an impact is applied to the burner body 20 from the downstream side to the upstream side, the check valve member 22B can prevent the burner body 20 from moving upstream.

[0039] In this embodiment, an inlet end sealing portion 30A and an outlet sealing portion 30B are formed, but sealing portions may be formed at positions other than the ends. In this case, as shown in Figure 6, sealing portions 32A are formed in the unit flow path 26A and sealing portion 32B is formed in the unit flow path 26B, and these are formed at different positions in the axial direction S within a range in which the area of ​​the flow path partition wall 28 through which the flammable gas permeates is greater than the cross-sectional area of ​​the unit flow paths 26A and 26B into which the flammable gas flows.

[0040] Furthermore, in this embodiment, the unit flow paths 26A and 26B have a rectangular cross-section, but the cross-section may be a polygon other than a rectangle (pentagon, hexagon, etc.). It may also be a circular cross-section. As in this embodiment, by using a polygonal shape, the flow path partition wall 28 between adjacent unit flow paths 26A and 26B can be made of a constant thickness, thereby reducing the pressure loss of the flammable gas.

[0041] Furthermore, in this embodiment, since a check valve member 22B is provided, even if an impact is applied to the burner body 20 from the downstream side to the upstream side, the check valve member 22B can prevent the burner body 20 from moving upstream.

[0042] Furthermore, in this embodiment, the mounting member 22 and the burner body 20 have a square cross-section, but as shown in Figures 7 and 8, the burner body 20R may have a circular cross-section. In this case, a cylindrical outer wall portion 24R corresponding to the outer wall portion 24 is formed, and the unit flow paths 26A and 26B form an overall flow path 26R with a circular cross-section. In addition, an expandable member 40R is arranged on the outer circumferential surface of the burner body 20R.

[0043] Furthermore, the burner body 20 of this embodiment and the modified burner body 20R may be formed as a burner body 20X by joining sectional parts 36A to 36D, which are divided along the axial direction S, with a joining member 42, as shown in Figure 9. In this case, the joining member 42 is a material that can expand and contract, similar to the expandable member 40R. With this configuration, the expansion and contraction of the burner body 20X can also be absorbed by the joining member 42. In addition, since the volume of each of the integrally molded sectional parts 36A to 36D can be reduced, the amount of expansion and contraction can also be reduced.

[0044] In this embodiment, the cross-sectional area of ​​the burner body 20, 20R, and the sub-parts 36A to 36D is 500 mm². 2 ~10000mm 2 It is preferable that it be within the range of 500mm. 2 Smaller sizes tend to result in higher pressure loss, such as 10,000 mm. 2 If the size is larger, it tends to become more difficult to manufacture in terms of moldability and other factors.

[0045] Alternatively, as shown in Figure 10, the burner body 20 may be configured in two parts, with two burner bodies 20-1 and 20-2 arranged in series within the mounting member 22 with an axial gap S R between them. Each of the burner bodies 20-1 and 20-2 is equipped with multiple unit flow paths 26A and 26B, an inlet end sealing section 30A, and an outlet sealing section 30B. In this case, the outlet 20B of the upstream burner body 20-1 does not constitute a flame retaining section. With this configuration, the gap R functions as a heat transfer suppression section, and heat transfer from the flame retaining section 21 to the inlet end 20A can be suppressed. Therefore, high-temperature ignition upstream of the gap R can be suppressed. [Explanation of symbols]

[0046] 10 Gas Burners 12. Flammable gas flow path 20, 20R, 20X Burner Body 20A inlet end 20B spout 21 Flame holding part 22 Mounting components 26, 26R Overall flow path 26A Unit channel 26B Unit channel 28 Flow channel partition 30A Inlet end sealing part 30B Spout sealing part 32A Sealing part 32B Sealing part R spacing (heat transfer suppression section)

Claims

1. The inlet end into which the flammable gas flows, A nozzle that releases flammable gas, A whole flow path is formed between the inlet end and the outlet, through which the flammable gas flows, The overall flow path is divided into multiple unit flow paths with a rectangular cross-section along an axis extending from the inlet end to the outlet, and the flow path partitions are made of porous ceramics that allow the flammable gas to pass through. Each of the aforementioned unit flow paths has a non-penetrating inlet end and outlet, and adjacent unit flow paths are provided with sealing portions at different positions in the flow direction of the flammable gas, A flame-holding section formed in the aforementioned nozzle to hold the flame, A burner body having, A mounting member for attaching the burner body to the flow path of the combustible gas, A gas burner equipped with a gas burner.

2. The inlet end into which the flammable gas flows, A nozzle that releases flammable gas, A whole flow path is formed between the inlet end and the outlet, through which the flammable gas flows, The overall flow path is divided into multiple unit flow paths with a rectangular cross-section along an axis extending from the inlet end to the outlet, and the flow path partitions are made of porous ceramics that allow the flammable gas to pass through. Each of the aforementioned unit flow paths has a non-penetrating inlet end and outlet, and adjacent unit flow paths are provided with sealing portions at different positions in the flow direction of the flammable gas, A flame-holding section formed in the aforementioned nozzle to hold the flame, A burner body having, A mounting member for attaching the burner body to the flow path of the combustible gas, Equipped with, An elastically deformable expandable / contractable member is disposed between the inner circumferential surface of the mounting member and the outer circumferential surface of the burner body. Gas burner.

3. A heat transfer suppression unit is provided between the nozzle and the inlet end to suppress heat transfer from the flame-holding unit to the inlet end side. A gas burner according to claim 1 or claim 2, further comprising the above.

4. The sealing portion includes an inlet end sealing portion that seals the inlet ends of some of the unit flow paths, and an outlet sealing portion that seals the remaining outlets of the unit flow paths. A gas burner according to claim 1 or claim 2.

5. The inlet end sealing portion and the outlet sealing portion are formed of porous ceramics made of the same material as the flow path partition. The gas burner according to claim 4.

6. The gas burner according to claim 4, wherein the inlet end sealing portion and the outlet sealing portion are alternately formed in adjacent unit flow paths.

7. The gas burner according to claim 1 or claim 2, further comprising a check member disposed on the upstream side of the burner body and preventing the burner body from moving upstream relative to the mounting member.

Images