CN222143043U

CN222143043U - Fire grate and burner

Info

Publication number: CN222143043U
Application number: CN202420639276.3U
Authority: CN
Inventors: 余浩伦; 张锦梁; 张上兵
Original assignee: Guangdong Vanward New Electric Co Ltd
Current assignee: Guangdong Vanward New Electric Co Ltd
Priority date: 2024-03-29
Filing date: 2024-03-29
Publication date: 2024-12-10
Anticipated expiration: 2034-03-29

Abstract

The utility model relates to the technical field of gas water heaters, and in particular to a fire grate and a burner. The fire grate is staggered with mutually unconnected gas channels and air channels along the width direction, and the air channels are arranged on both sides of each of the gas channels; the top of the fire grate is provided with a connected air outlet corresponding to each of the air channels, and the top of the fire grate is provided with a plurality of fire holes along the length direction corresponding to each of the gas channels; two adjacent fire holes are staggered along the length direction of the fire grate. The gas ejected from the fire hole is cross-mixed with the air flowing out of the air outlet holes on both sides, and at the same time, by staggering the plurality of fire holes along the length direction, the contact area between the gas and the air at the fire hole is further increased, the mixing effect of the gas and the air is improved, the combustion time of the gas is reduced, and the combustion efficiency and the stability of the combustion are improved.

Description

Fire grate and burner

Technical Field

The utility model relates to the technical field of gas water heaters, in particular to a fire grate and a burner.

Background

At present, some used fuel gases have the characteristics of 1) small ignition energy, extremely easy ignition, 2) high combustion speed, concentrated combustion area, short flame and 3) very high propagation speed of premixed combustion flame, and outstanding backfire problem during low-load operation. Therefore, the above-mentioned fuel gas is usually burned in the burner by post-premixing combustion, so as to solve the tempering problem, but the fuel gas and air still cannot be mixed uniformly in time, and the mixing effect is poor, so that the combustion problems of low combustion efficiency, unstable combustion and the like are caused.

Disclosure of utility model

One of the technical problems to be solved by the utility model is to provide a fire grate which can effectively solve the technical problems of low combustion efficiency and unstable combustion caused by poor mixing effect of fuel gas in a post-premixing mode in the prior art.

The second technical problem to be solved by the utility model is to provide a burner which can effectively solve the technical problems of low combustion efficiency and unstable combustion caused by poor mixing effect of the fuel gas in a post-premixing mode in the prior art.

The first technical problem is solved by the following technical scheme:

The fire grate is characterized in that gas channels and air channels which are not communicated with each other are alternately arranged in the fire grate in the width direction, the air channels are arranged on two sides of each gas channel, the top end of the fire grate is provided with communicated air outlet holes corresponding to each air channel, the top end of the fire grate is provided with a plurality of fire holes corresponding to each gas channel in the length direction, and two adjacent fire holes are arranged in a staggered mode in the length direction of the fire grate.

Compared with the background technology, the fire grate has the beneficial effects that:

The fire grate is suitable for the fuel gas with small ignition energy, easy ignition and high combustion speed, and the fuel gas channel and the air channel are not communicated with each other, so that the fuel gas flows out from the fire hole and is premixed with the air after the fuel gas flows out from the fire hole, and tempering is avoided. And the gas sprayed out of the fire holes is mixed with the air flowing out of the air outlets on two sides in a cross manner, and two adjacent fire holes corresponding to the same gas channel are arranged in a staggered manner along the length direction of the fire row, so that the contact area of the gas at the fire holes and the air flowing out of the air outlets is further increased, the mixing effect of the gas and the air is improved, the load is reduced to be too concentrated, the occurrence of a local combustion high-temperature area is avoided, the combustion time of the gas is reduced, the combustion efficiency and the combustion stability are improved, and the combustion problem of deflagration or detonation caused by tempering is avoided.

In one embodiment, the plurality of fire holes at least include left fire holes and right fire holes which are arranged in a staggered manner along the length direction, the left fire holes are obliquely arranged towards the left side in the width direction, and the right fire holes are obliquely arranged towards the right side in the width direction.

In one embodiment, the included angle between the left fire hole and the right fire hole is 50-70 degrees.

In one embodiment, a middle fire hole is arranged between the adjacent left fire hole and right fire hole along the length direction of the fire row, and the middle fire hole is arranged vertically.

In one embodiment, the median fire hole length is shorter than the lengths of the left and right fire holes.

In one embodiment, the fire holes extend along the length of the fire row.

In one embodiment, each of the air outlet holes is provided with a turbulence structure.

In one embodiment, the fire grate comprises an inner shell and an outer shell, wherein the gas channel is arranged in the inner shell, and a plurality of fire holes are arranged at the top end of the inner shell in a staggered manner along the length direction;

The outer shell is sleeved on the inner shell and encloses two air channels with the inner shell, the top end of the outer shell and the top end of the side wall of the inner shell enclose the air outlet, and the top end of the outer shell is provided with a turbulent convex hull protruding towards the inner shell so as to form the turbulent structure.

In one embodiment, the outer shell comprises two coamings which are oppositely arranged along the width direction, the top ends of the coamings are provided with the turbulent convex hulls, the turbulent convex hulls of the coamings which are positioned on the left side of the inner shell along the width direction are in one-to-one opposite arrangement with the right fire holes, and the turbulent convex hulls of the coamings which are positioned on the right side of the inner shell along the width direction are in one-to-one opposite arrangement with the left fire holes.

In one embodiment, the top end of the outer shell is provided with a guiding flange extending obliquely upwards towards the inner shell.

In one embodiment, the two side walls of the inner shell along the width direction are provided with first convex hulls outwards in a convex mode, and the two inner side walls of the outer shell are provided with second convex hulls outwards in a convex mode.

The second technical problem is solved by the following technical scheme:

The burner comprises a main shell and a plurality of fire rows, wherein the fire rows are arranged in the main shell at intervals along the width direction.

Compared with the background technology, the burner has the beneficial effects that:

Drawings

FIG. 1 is a schematic view of a fire grate provided in an embodiment of the present utility model;

FIG. 2 is a top view of a fire grate provided by an embodiment of the present utility model;

FIG. 3 is a schematic view of the structure of an inner shell according to an embodiment of the present utility model;

FIG. 4 is an exploded view of a fire grate provided in accordance with an embodiment of the present utility model;

FIG. 5 is a schematic diagram of the flow paths of the fuel gas and air at the left fire hole provided by the embodiment of the utility model;

FIG. 6 is a schematic diagram of the flow paths of gas and air at the right fire hole provided by the embodiment of the utility model;

FIG. 7 is a schematic diagram of the flow paths of the gas and air at the median fire hole provided by the embodiment of the utility model.

The parts in the figures are named and numbered as follows:

10. Gas channel, 20, air channel, 30, fire hole, 301, left fire hole, 302, right fire hole, 303, middle fire hole, 40, air outlet hole;

1. An inner case; 11, an injection hole, 12, a first convex hull, 13, a choke convex hull;

2. The device comprises a shell, a coaming, 211, a turbulent convex hull, 212, a guiding flanging, 213 and a second convex hull.

Detailed Description

In order to make the technical problems solved, the technical scheme adopted and the technical effects achieved by the utility model more clear, the technical scheme of the utility model is further described below by a specific embodiment in combination with the attached drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting thereof. It should be further noted that, for convenience of description, only some, but not all of the drawings related to the present utility model are shown.

In the description of the present utility model, unless explicitly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, and may, for example, be fixedly connected, detachably connected, or integrally formed, mechanically connected, electrically connected, directly connected, indirectly connected through an intervening medium, or in communication between two elements or in an interaction relationship between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

In the description of the present embodiment, the terms "upper", "lower", "right", "left", and the like are orientation or positional relationships based on those shown in the drawings, merely for convenience of description and simplicity of operation, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the utility model. Furthermore, the terms "first," "second," and the like, are used merely for distinguishing between descriptions and not for distinguishing between them.

The technical scheme of the utility model is further described below by the specific embodiments with reference to the accompanying drawings.

The embodiment provides a burner which is used in equipment such as a gas water heater. Specifically, the burner includes a main housing and a plurality of fire rows disposed in the main housing at intervals in a width direction. The fuel gas is mixed with air at the fire holes of the fire row in a post-premixing mode and then burnt to generate high-temperature flue gas so as to heat water flowing through the heat exchanger.

At present, some used fuel gas has the characteristics of small ignition energy, easy ignition, high combustion speed, concentrated combustion area, short flame, very high propagation speed of premixed combustion flame, prominent backfire problem in low-load operation, low energy emissivity of flame to a furnace tube, local heat accumulation at an outlet of the burner, very high flue gas temperature, uneven temperature distribution in the furnace and the like. Therefore, the fuel gas is combusted in the combustor in a post-premixing mode, so that the problem that the fuel gas and the air cannot be uniformly mixed in time and the mixing effect is poor, and combustion problems such as low combustion efficiency and unstable combustion are caused easily.

In order to solve the above-mentioned problems, as shown in fig. 1-5, the present embodiment further provides a fire grate, in which gas channels 10 and air channels 20 that are not communicated with each other are staggered along the width direction (left-right direction in the figure), and two sides of each gas channel 10 are provided with air channels 20. The top of fire row corresponds every air channel 20 and all is provided with the venthole 40 that is linked together, and the top of fire row corresponds every gas channel 10 and all is provided with a plurality of fire holes 30 along length direction (the fore-and-aft direction in the figure), and adjacent two fire holes 30 are along the length direction dislocation set of fire row, and every fire hole 30 all extends along the length direction of fire row. The air in the air channel 20 flows out through the air outlet holes 40, so that the gas sprayed out of the fire holes 30 is mixed with the air flowing out of the air outlet holes 40 on two sides in a cross manner, and meanwhile, two adjacent fire holes 30 corresponding to the same gas channel 10 are arranged in a staggered manner along the length direction of the fire row, so that the contact area between the gas at the fire holes 30 and the air flowing out of the air outlet holes 40 is further increased, the mixing effect of the gas and the air is improved, the load is reduced to be too concentrated, the occurrence of a local combustion high-temperature area is avoided, the combustion time of the gas is shortened, the combustion efficiency and the combustion stability are improved, and the combustion problem of deflagration or detonation caused by tempering is avoided.

In one embodiment, as shown in fig. 2 and 3, the plurality of fire holes 30 includes at least a left fire hole 301 and a right fire hole 302 that are offset in the longitudinal direction, the left fire hole 301 being inclined toward the left side in the width direction, and the right fire hole 302 being inclined toward the right side in the width direction. Through the left fire holes 301 and the right fire holes 302 which are arranged in a staggered way, the contact surface between the fire holes 30 and the air at the air outlet holes 40 on the left side and the right side is increased, and the cross mixing effect of the fuel gas and the air is improved.

It should be noted that, the included angle between the left fire hole 301 and the right fire hole 302 is 50 ° -70 °, so that the left fire hole 301 and the right fire hole 302 have a suitable inclination angle, and the processing difficulty of the left fire hole 301 and the right fire hole 302 can be reduced while the large contact area with air is ensured. If the inclination angles of the left fire hole 301 and the right fire hole 302 are too large, the processing difficulty and the processing cost of the fire hole 30 are increased. If the inclination angle of the left fire hole 301 and the right fire hole 302 is too small, the mixing effect of the gas in the fire hole 30 and the air in the air outlet hole 40 is not obviously improved.

Specifically, as shown in fig. 3, a median fire hole 303 is provided between adjacent left and right fire holes 301 and 302. The left fire hole 301, the middle fire hole 303 and the right fire hole 302 are arranged in a staggered manner along the length direction, the left fire hole 301 is positioned on the left side of the middle fire hole 303, the right fire hole 302 is positioned on the right side of the middle fire hole 303, and the middle fire hole 303 is vertically arranged. The fire hole 30 of the present embodiment has three types of left fire holes 301, middle fire holes 303, and right fire holes 302. In other embodiments, the fire holes 30 may have other inclination angles, and the fire holes 30 with different inclination angles are arranged in a staggered manner along the length direction.

In one embodiment, the length of the middle fire hole 303 is shorter than the lengths of the left fire hole 301 and the right fire hole 302. Because left fire hole 301, right fire hole 302 still play the vortex effect to the air for gas and air mixing are more even, consequently with the length setting of middle position fire hole 303 length short left fire hole 301 and right fire hole 302, on satisfying the even basis of flame distribution, make gas and air intensive mixing.

In one embodiment, each of the air outlet holes 40 is provided with a turbulence structure to cause turbulence in the air flowing through the air outlet holes 40. The turbulence structure enables the air near the fire hole 30 to generate better turbulence effect, and enhances the collision mixing effect of the air and the fuel gas.

In one embodiment, as shown in fig. 4 and 5, the fire grate includes an inner casing 1 and an outer casing 2, a gas passage 10 is provided inside the inner casing 1, and a plurality of fire holes 30 are provided at the top end of the inner casing 1 in a staggered manner in the length direction. The outer shell 2 is sleeved on the inner shell 1 and encloses two air channels 20 with the inner shell 1. The top of the outer casing 2 and the top of the side wall of the inner casing 1 enclose an air outlet hole 40, and the top of the outer casing 2 is provided with a turbulence convex hull 211 protruding towards the inner casing 1 to form a turbulence structure. Specifically, the outer shell 2 includes two coamings 21 that set up relatively along width direction, and the inner shell 1 presss from both sides and locates between two coamings 21, and two lateral walls of inner shell 1 along width direction enclose into an air channel 20 with corresponding coamings 21 respectively, through setting up vortex convex hull 211 for the air that the venthole 40 of fire hole 30 left and right sides flows out has the turbulent flow effect, forms the single channel dislocation mixed combustion mode of air (turbulence) -gas (dislocation flow) -air (turbulence) at the top of fire row.

Specifically, the inner case 1 is formed by symmetrically attaching left and right side plates having the same structure and forms a gas passage 10 inside thereof. The edges of the two side plates of the inner shell 1 are attached to each other, and a good seal of the gas channel 10 is achieved. The edge of the inner shell 1 is closed, an injection hole 11 communicated with the gas channel 10 is formed at the front side of the bottom, and the gas entering from the injection hole 11 flows to the fire hole 30 at the top end of the fire row through the gas channel 10, and finally the gas and the air are fully mixed and combusted.

In one of the embodiments, as shown in fig. 3 and 4, at least one of the two side walls of the inner case 1 in the width direction is provided with a flow blocking convex hull 13 protruding into the gas passage 10. By punching the two side walls of the inner shell 1 to form the flow blocking grooves, the flow blocking grooves are recessed towards the gas channel 10 and form the flow blocking convex hulls 13 in the gas channel 10, so that the gas is uniformly distributed at the flow blocking convex hulls 13, the pressure balance inside the gas channel 10 is ensured, and the gas uniformly flows to the fire holes 30 above. Both side walls of the inner case 1 of the present embodiment in the width direction are provided with flow-blocking convex hulls 13 to enhance the uniform flow effect of the fuel gas in the fuel gas channel 10. In other embodiments, the choke convex hull 13 may also be provided on any one of the side walls of the inner housing 1.

In one embodiment, as shown in fig. 4 and 5, the two side walls of the inner shell 1 along the width direction are both provided with the first convex hull 12 in an outward convex manner, the two inner side walls (i.e. the coaming 21) of the outer shell 2 are both provided with the second convex hull 213 in an outward convex manner, and by providing the first convex hull 12 and the second convex hull 213, a turbulent flow result is formed in the air channel 20 in the fire row, so that the turbulent flow effect of the air formed in the air outlet holes 40 is further enhanced. Meanwhile, the top ends of the first convex hulls 12 are abutted against the top ends of the second convex hulls 213 in a one-to-one correspondence. When the inner shell 1 and the outer shell 2 are assembled, the first convex hull 12 and the second convex hull 213 are abutted tightly to lock the relative positions of the inner shell 1 and the outer shell 2, so that good positioning and limiting effects can be achieved, and dislocation of the inner shell 1 and the outer shell 2 is avoided. And the connection strength of the inner shell 1 and the outer shell 2 is improved, so that the overall structural stability of the fire grate is improved. The inner shell 1 of this embodiment is provided with a plurality of first convex hulls 12 at equal heights and equidistant in the front-rear direction on both sides thereof, and two coamings 21 are correspondingly provided with a plurality of second convex hulls 213 at equal heights and equidistant in the front-rear direction. It will be appreciated that the number, spacing distance and mounting height of the first and second convex hulls 12, 213 may be flexibly adjusted.

As shown in fig. 1, 5 and 6, the top end of each shroud 21 has a spoiler convex hull 211, and the spoiler convex hulls 211 on each shroud 21 are arranged in a staggered manner along the length direction, the spoiler convex hulls 211 of the shroud 21 located on the left side of the inner shell 1 along the width direction are arranged in a one-to-one opposite manner to the right fire holes 302, and the spoiler convex hulls 211 of the shroud 21 located on the right side of the inner shell 1 along the width direction are arranged in a one-to-one opposite manner to the left fire holes 301. Because the turbulent convex hull 211 of the coaming 21 on the left side is concave towards the right fire hole 302, the left air outlet hole 40 of the right fire hole 302 is close to the right fire hole 302 as much as possible, which is beneficial to improving the mixing effect of the air at the left air outlet hole 40 and the fuel gas at the right fire hole 302. Similarly, as the turbulent convex hull 211 of the coaming 21 on the right side is concave towards the left fire hole 301, the right air outlet hole 40 on the right opposite to the left fire hole 301 is close to the left fire hole 301 as much as possible, which is beneficial to improving the mixing effect of the air at the right air outlet hole 40 and the fuel gas at the left fire hole 301. The middle fire hole 303 is formed between the side wall of the spoiler convex hull 211 of the shroud 21 located on the left side and the side wall of the adjacent spoiler convex hull 211 of the shroud 21 located on the right side.

In one of the embodiments, shown in fig. 1, the top end of the outer shell 2 is provided with a guide flange 212 sloping upwards towards the inner shell 1. Specifically, the top end of the shroud 21 between two adjacent spoiler flanges 211 and the top wall of the spoiler flange 211 are each provided with a guide flange 212 extending obliquely upward toward the inner shell 1. By providing the guide flanges 212, the top ends of the fire bars form a single-channel staggered mixed combustion mode of air (turbulence orientation) -fuel gas (staggered flow) -air (turbulence orientation). Specifically, the air of the left and right air outlet holes 40 directionally flows towards the fire hole 30 under the guiding action of the guiding flanges 212 of the two coamings 21 (as shown by arrows in fig. 4-6), so that most of the air at the air outlet holes 40 at the left and right sides directionally flows to the fire hole 30 at the middle position, and the mixing effect and the combustion efficiency of the fuel gas and the air are improved. Since the median fire hole 303 extends in the length direction (i.e., is vertically disposed), the two side walls of the spoiler convex hull 211 do not need to be provided with the guide flanges 212 in an extending manner.

In one embodiment, the guide flange 212 is inclined at an angle α of 10 ° to 20 ° with respect to the height direction of the shroud 21. Specifically, the inclination angle α of the guide flange 212 may be 10 °,12 °,14 °,16 °,18 °,20 °, or the like. By setting the inclination angle α to the above-described value, the guide flange 212 guides as much of the air as possible to flow through the air outlet holes 40 in a directed manner to the fire hole 30 located at the intermediate position. If the inclination angle α is too small, the guiding effect of the guiding flange 212 is not obvious, and if the inclination angle α is too large, the opening area of the air outlet 40 is reduced, which has a certain blocking effect on the directional flow of air and is unfavorable for the supply of air.

As shown in figures 5-7, the flow path of the fuel gas in the fire row is that the fuel gas is ejected from the nozzle of the gas distribution pipe assembly at a certain flow rate under the ejection effect of the gas distribution pipe assembly of the fuel gas water heater (or the wall-mounted boiler) and enters the fuel gas channel 10 through the ejection hole 11 of the inner shell 1 of the fire row. Then, the fuel gas is uniformly split after passing through the flow blocking convex hulls 13 in the fuel gas channel 10 and uniformly flows to the fire holes 30 at the top end of the fuel gas channel 10, so that the fuel gas is uniformly combusted.

The flow path of the air in the fire row is that the air enters the left air channel 20 and the right air channel 20 from bottom to top respectively under the action of the fan component of the gas water heater. As shown in fig. 5, at the left fire hole 301, the air of the left air outlet hole 40 is turbulent under the action of the turbulent convex hull 211 of the shroud 21 on the left, and simultaneously, the air is directed to the left fire hole 301 under the guiding action of the guiding flange 212 at the top end of the shroud 21 on the left. The air of the air outlet holes 40 on the right side generates turbulence effect under the action of the turbulence convex hulls 211 of the coaming 21 on the right side and deviates near the left fire hole 301, and meanwhile, directional turbulence flow is realized towards the left fire hole 301 under the guiding action of the guiding flanges 212 at the top end of the coaming 21 on the right side, so that the air of the air outlet holes 40 on the left side and the air outlet holes 40 on the right side are collided and mixed with fuel gas flowing out of the left fire hole 301. As shown in fig. 6, at the right fire hole 302, the air of the right air outlet hole 40 is turbulent under the action of the turbulent convex hull 211 of the shroud 21 on the right, and simultaneously, the air is directed to the right fire hole 302 under the guiding action of the guiding flange 212 at the top end of the shroud 21 on the right. The air of the left air outlet holes 40 generates turbulence effect under the action of the turbulence convex hulls 211 of the left coaming plate 21 and deviates near the right fire holes 302, and meanwhile, directional turbulence flow is realized towards the right fire holes 302 under the guiding action of the guiding flanges 212 at the top ends of the left coaming plate 21, so that the air of the left air outlet holes 40 and the air of the right air outlet holes 40 are collided and mixed with fuel gas flowing out of the right fire holes 302. As shown in fig. 7, at the middle fire hole 303, the air of the left air outlet hole 40 generates turbulence effect under the action of the turbulence convex hull 211 of the shroud 21 on the left, and the air of the right air outlet hole 40 generates turbulence effect under the action of the turbulence convex hull 211 of the shroud 21 on the right, so that the air of the air outlet holes 40 on the left and right sides are collided and mixed with the fuel gas flowing out from the middle fire hole 303.

The above embodiments merely illustrate the basic principle and features of the present utility model, and the present utility model is not limited to the above embodiments, but may be varied and altered without departing from the spirit and scope of the present utility model. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims

1. The fire grate is characterized in that gas channels (10) and air channels (20) which are not communicated with each other are arranged in the fire grate in a staggered mode in the width direction, the air channels (20) are arranged on two sides of each gas channel (10), vent holes (40) which are communicated with each other are formed in the top ends of the fire grate corresponding to each air channel (20), a plurality of fire holes (30) are formed in the top ends of the fire grate corresponding to each gas channel (10) in the length direction, and two adjacent fire holes (30) are arranged in a staggered mode in the length direction of the fire grate.

2. The fire grate of claim 1, wherein the plurality of fire holes (30) includes at least a left fire hole (301) and a right fire hole (302) that are offset in the longitudinal direction, the left fire hole (301) being inclined toward the left side in the width direction, and the right fire hole (302) being inclined toward the right side in the width direction.

3. A fire row according to claim 2, characterized in that the left fire hole (301) is at an angle of 50 ° to 70 ° to the right fire hole (302).

4. Fire grate according to claim 2, characterized in that, in the length direction of the fire grate, a middle fire hole (303) is arranged between the adjacent left fire hole (301) and right fire hole (302), and the middle fire hole (303) is arranged vertically.

5. The fire row according to claim 4, characterized in that the length of the median fire hole (303) is shorter than the lengths of the left fire hole (301) and the right fire hole (302).

6. A fire grate according to claim 1, characterized in that the fire holes (30) extend in the length direction of the fire grate.

7. A fire grate as claimed in claim 2 or 4, wherein each of the air outlet holes (40) is provided with a spoiler arrangement.

8. The fire grate of claim 7, wherein the fire grate comprises an inner shell (1) and an outer shell (2), the gas channel (10) is arranged inside the inner shell (1), and a plurality of fire holes (30) are arranged at the top end of the inner shell (1) in a staggered manner along the length direction;

The outer shell (2) is sleeved on the inner shell (1) and encloses two air channels (20) with the inner shell (1), the top end of the outer shell (2) and the top end of the side wall of the inner shell (1) enclose an air outlet hole (40), and a turbulent convex hull (211) protruding towards the inner shell (1) is arranged at the top end of the outer shell (2) so as to form the turbulent structure.

9. The fire grate of claim 8, wherein the outer shell (2) comprises two coamings (21) which are oppositely arranged along the width direction, the top ends of the coamings (21) are provided with the turbulent convex hulls (211), the turbulent convex hulls (211) of the coamings (21) which are positioned on the left side of the inner shell (1) along the width direction are arranged in a one-to-one opposite mode with the right fire holes (302), and the turbulent convex hulls (211) of the coamings (21) which are positioned on the right side of the inner shell (1) along the width direction are arranged in a one-to-one opposite mode with the left fire holes (301).

10. A fire grate according to claim 8, characterized in that the top end of the outer shell (2) is provided with a guiding flange (212) extending obliquely upwards towards the inner shell (1).

11. Fire grate according to claim 8, characterized in that the two side walls of the inner shell (1) along the width direction are provided with first convex hulls (12) outwards, and the two inner side walls of the outer shell (2) are provided with second convex hulls (213) outwards.

12. A burner comprising a main casing and a plurality of fire rows according to any one of claims 1 to 11, the plurality of fire rows being disposed in the main casing at intervals in a width direction.