Flame stabilizing fire cover for combustor and combustor

Abstract

A flame stabilizing fire cover for a combustor comprises a fire cover body, the fire cover body is provided with a gas mixing cavity with a downward opening, a main fire hole communicated with the gas mixing cavity is formed in the outer side wall of the fire cover body, and an annular groove surrounding the outer side wall is formed in an outlet of the main fire hole. The annular groove is inwards cut in the axis direction of the main fire hole; the distance from the circumferential edge of the end, close to the inlet of the main fire hole, of the longitudinal section of the annular groove to the axis of the main fire hole is smaller than the distance from the circumferential edge of the end, located at the outlet of the main fire hole, of the longitudinal section of the annular groove to the axis of the main fire hole. Compared with the prior art, the technical scheme provided by the utility model has the advantages that the design is more excellent, the gas supplementing and flame stabilizing effects are more obvious, the combustion is more sufficient, and the processing difficulty is not increased.

Description

Technical Field

[0001] The utility model relates to the field of fire covers, in particular to a flame-stabilizing fire cover for a burner. Background Art

[0002] At present, the multiple main fire holes opened by the fire cover of the burner are basically independent of each other. The flame separation phenomenon of this fire cover is very obvious (the flame is separated from the fire hole, and sometimes the flame can be seen to vibrate violently or even erratic. This phenomenon is called "flame separation"), and there is a problem of low thermal efficiency. Therefore, in order to improve the combustion stability, a few manufacturers will set a circle of flame stabilizing holes and / or flame stabilizing grooves above or below the main fire hole to strengthen the flame intensity and improve the combustion stability. However, the flame stabilizing effect of this structural design is often limited, and it is impossible to fundamentally solve the problem of rapid decline of the main fire hole gas flow rate from the main fire hole inlet to the main fire hole outlet, and it is also impossible to achieve the purpose of mutual flame stabilization between adjacent main fire holes from the root of the flame. Therefore, it is impossible to effectively reduce the tendency of flame separation. For example, the Chinese utility model patent with the authorization announcement number CN201155762Y and the title of the stove head fire cover discloses: a stove head fire cover, a plurality of main fire holes and flame stabilizing holes are provided on the fire cover, and at least one ring groove is provided on the peripheral surface of the fire cover below the main fire hole, and a plurality of flame stabilizing holes are arranged in the ring groove at intervals. The technical solution described in the utility model adopts the technical solution of flame stabilization by superimposing flame stabilization grooves to achieve the purpose of flame stabilization, but the above-mentioned problems of poor effect and inability to stabilize flames with each other still exist.

[0003] Based on the above technical problems, some manufacturers have further developed a solution in which the annular groove is connected to the main fire hole in order to obtain a better flame stabilization effect. For example, the Chinese utility model patent with the authorization announcement number CN213421093U and the title of stove fire cover discloses: the stove fire cover includes a fire cover body, the fire cover body includes a circular outer wall, the outer wall is provided with a plurality of main fire holes, the outer wall is also provided with a plurality of air guide blind holes, and the outer surface of the outer wall is provided with a plurality of annular grooves, and the plurality of annular grooves are all recessed inward and connected with the plurality of main fire holes and the plurality of air guide blind holes. However, from the perspective of structural design, the technical solution described in the utility model cannot achieve the purpose of rapidly reducing the gas flow rate from the main fire hole inlet to the main fire hole outlet. Even if the annular groove is connected to the main fire hole to supplement air and stabilize the flame, the effect cannot reach the ideal state.

[0004] In addition, some manufacturers have proposed a design that is superior to the above scheme, which uses a scheme of superimposing annular grooves on the main fire holes to further expand the air intake cross section. For example, the Chinese utility model patent with the authorization announcement number CN205402715U and entitled a burner flame stabilizing fire cover discloses: including a fire cover body (1), a gas mixing chamber (2) on the lower end surface of the fire cover body (1), a plurality of main fire holes (3) communicating with the gas mixing chamber (2) are provided between the outer side and the inner side of the fire cover body (1), and an annular groove (4) is provided at the outlet of the main fire hole (3) on the fire cover body (1). However, the technical scheme described in the utility model does not make further optimization in terms of rapidly reducing the gas flow rate from the main fire hole inlet to the main fire hole outlet, so the actual flame stabilizing effect does not reach the extreme state. Utility Model Content

[0005] Based on the above technical problems, the utility model provides a flame stabilizing cover for a burner and a burner with better design, more significant gas replenishment and flame stabilizing effects, more complete combustion, and no increased processing difficulty.

[0006] The utility model mainly adopts the following technical solutions:

[0007] A flame-stabilizing fire cover for a burner comprises a fire cover body, the fire cover body having an air mixing chamber opening downward, an outer wall of the fire cover body being provided with a main fire hole communicating with the air mixing chamber, an annular groove surrounding the outer wall being formed at the outlet of the main fire hole, the annular groove cutting inwardly along the axial direction of the main fire hole, a distance from a circumferential edge of a longitudinal cross section of the annular groove at one end close to an inlet of the main fire hole to the axis of the main fire hole being smaller than a distance from a circumferential edge of a longitudinal cross section of the annular groove at one end located at an outlet of the main fire hole to the axis of the main fire hole.

[0008] Wherein, the width of the annular groove at the outlet of the main fire hole is smaller than the aperture of the main fire hole, so that the annular groove passes through the main fire hole.

[0009] Wherein, the longitudinal cross-section of the annular groove is one of a "convex" shape, a "{" shape, a knife handle shape, a pen tip shape, a triangle, and a trapezoid.

[0010] Wherein, the angle between the axis direction of the main fire hole and the horizontal direction is 0 to 60°.

[0011] Wherein, the maximum width of the annular groove is between 0.5 mm and 1.8 mm.

[0012] The cutting depth of the annular groove is between 2 mm and 6 mm, and the ratio of the cutting depth of the annular groove to the length of the main fire hole is between 0.2 and 0.75.

[0013] Wherein, a limiting protrusion protruding downward is also formed at the bottom end of the outer side wall.

[0014] Among them, the outer wall is arranged opposite to the inner wall of the fire cover body and together with the top wall of the fire cover body, encloses the gas mixing chamber. The top wall extends obliquely inward and downward and protrudes from the inner wall to form an energy-gathering edge.

[0015] Among them, the outer wall is also provided with a flame stabilizing hole and / or a flame stabilizing groove connected with the gas mixing chamber, and the flame stabilizing hole and / or the flame stabilizing groove are located above and / or below the main fire hole, and the aperture of the flame stabilizing hole is smaller than the aperture of the main fire hole and / or the width of the flame stabilizing groove is smaller than the aperture of the main fire hole.

[0016] Wherein, a plurality of the main fire holes are circumferentially distributed on the outer side wall, and at least a portion of the main fire holes have reduced apertures and are arranged at intervals to form a furnace frame fire avoidance zone.

[0017] A burner adopts the flame stabilizing cover for the burner.

[0018] According to the technical scheme described in the utility model, the following beneficial effects are achieved: the distance from the circumferential edge of the longitudinal section of the annular groove cut inward along the axis of the main fire hole to the axis of the main fire hole is less than the distance from the circumferential edge of the longitudinal section of the annular groove at one end near the main fire hole inlet to the axis of the main fire hole. This "narrow inside and wide outside" structural design can not only reduce the gas flow resistance at the outlet of the main fire hole, but also facilitate the rapid cutting off of the gas supply from the inlet of the main fire hole to the outlet of the main fire hole, thereby reducing the flame separation phenomenon; it can also increase the air intake area at the outlet of the main fire hole, which is conducive to the replenishment of primary air, so that the gas and air are mixed more fully, the oxygen is replenished more fully, the combustion is more complete, and the flame temperature is higher. In addition, the main fire holes that are independent of each other are connected in series through the annular groove, so that the adjacent main fire holes are mutually restrained from the root of the flame to achieve the purpose of flame stabilization. Moreover, the alternating arrangement of the main fire holes and the annular grooves also lengthens the boundary line of the main fire hole, increases the contact area between the gas and the air to achieve secondary air replenishment, and the combustion is more complete. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the fire cover shown in the first embodiment of the present application.

[0020] Figure 2 for Figure 1 Schematic diagram of the longitudinal section structure of the medium fire cover.

[0021] Figure 3 To show that the longitudinal section of the annular groove is trapezoidal Figure 2 Enlarged view of part B in the middle.

[0022] Figure 4 To show that the longitudinal section of the annular groove is triangular Figure 2 Enlarged view of part B in the middle.

[0023] Figure 5 To show that the longitudinal section of the annular groove is a "convex" shape Figure 2 Enlarged view of part B in the middle.

[0024] Figure 6 To show that the longitudinal section of the annular groove is "{"-shaped Figure 2 Enlarged view of part B in the middle.

[0025] Figure 7 To show that the longitudinal section of the annular groove is shank-shaped Figure 2 Enlarged view of part B in the middle.

[0026] Figure 8 This is the fire cover shown in the second embodiment of the present application.

[0027] Fig. 9 for Figure 8 Flat view of the fire cover.

[0028] Fig.10 This is the fire cover shown in the third embodiment of the present application.

[0029] Fig.11 for Fig.10 Flat view of the fire cover.

[0030] 1 fire cover body, 10 gas mixing chamber, 11 outer side wall, 111 limiting protrusion, 12 inner side wall, 13 top wall, 131 energy gathering edge, 20 main fire hole, 21 inlet, 22 outlet, 30 annular groove, 40 flame stabilizing hole, A furnace frame fire avoidance area. DETAILED DESCRIPTION

[0031] The technical solution of the utility model is further described below in conjunction with the accompanying drawings:

[0032] See also Figures 2 to 7As shown, a flame-stabilizing fire cover for a burner comprises a fire cover body 1, the fire cover body 1 has a mixing chamber 10 opening downward, an outer wall 11 of the fire cover body 1 is provided with a main fire hole 20 communicating with the mixing chamber 10, an annular groove 30 surrounding the outer wall 11 is formed at an outlet 22 of the main fire hole 20, the annular groove 30 is cut inwardly along the axial direction of the main fire hole 20, and a distance from a circumferential edge of a longitudinal section of the annular groove 30 at an end near an inlet 21 of the main fire hole 20 to the axis of the main fire hole 20 is smaller than a distance from a circumferential edge of a longitudinal section of the annular groove 30 at an end located at an outlet 22 of the main fire hole 20 to the axis of the main fire hole 20. In the present application, the annular groove adopts such a "narrow inside and wide outside" design, which can not only reduce the gas flow resistance at the outlet of the main fire hole, facilitate the rapid cutting off of the gas supply from the main fire hole inlet to the outlet of the main fire hole, thereby reducing the flame separation phenomenon; but also can increase the air intake area at the outlet of the main fire hole, which is conducive to the replenishment of primary air, so that the gas and air are mixed more fully, the oxygen replenishment is more sufficient, the combustion is more complete, and the flame temperature is higher. Compared with the design of "equal width inside and outside" of the annular groove in the prior art, it can significantly improve the speed of cutting off the gas supply from the inlet of the main fire hole to the outlet of the main fire hole, the flame stabilization effect is more obvious, and the thermal efficiency is as high as 80% or more (the national standard first-level energy efficiency is 63%). In addition, the independent main fire holes are connected in series through the annular groove, so that the adjacent main fire holes are mutually restrained from the root of the flame to achieve the purpose of flame stabilization. Moreover, the alternating arrangement of the main fire hole and the annular groove also lengthens the boundary line of the main fire hole, increases the contact area between the gas and the air to achieve secondary air replenishment, and the combustion is more complete. Preferably, the longitudinal cross-section of the annular groove 30 can adopt a gradually widening structural design or a staged widening structural design from the circumferential edge of the longitudinal cross-section of the annular groove 30 at one end near the inlet 21 of the main fire hole 20 to the circumferential edge of the longitudinal cross-section of the annular groove 30 at one end located at the outlet 22 of the main fire hole 20. In actual production, in order to further reduce the difficulty of processing, it is faster and more convenient to adopt a gradually widening structural design. Please note that the "circumferential edge" of the above-mentioned longitudinal cross-section of the annular groove refers to the contour formed by the groove walls on both sides of the annular groove in its longitudinal cross-section.

[0033] See also Figures 1 to 11 As shown, the width of the annular groove 30 at the outlet 22 of the main fire hole 20 is smaller than the aperture of the main fire hole 20, so that the annular groove 30 runs through the main fire hole 20. Preferably, the width of the annular groove 30 at the outlet 22 of the main fire hole 20 is smaller than the radius of the main fire hole 20, so as to ensure that the mixing ratio of gas and air will not be affected by excessive air intake. In the present application, the main fire hole and the annular groove are arranged alternately, which lengthens the boundary line of the main fire hole, increases the contact area between the gas and the air, realizes secondary air replenishment, and burns more fully.

[0034] See also Figures 2 to 7As shown, the longitudinal cross section of the annular groove 30 is one of a "convex" shape, a "{" shape, a handle shape, a pen tip shape, a triangle, and a trapezoid. Preferably, the longitudinal cross section of the annular groove 30 is a trapezoid, which is more convenient for machine tools to process. More preferably, the offset angle of the two waists of the trapezoid is 5°.

[0035] See also Figures 2 to 7 As shown, the angle between the axis direction of the main fire hole 20 and the horizontal direction is 0 to 60°.

[0036] See also Figures 2 to 7 As shown, the maximum width of the annular groove 30 is between 0.5 mm and 1.8 mm.

[0037] See also Figures 2 to 7 As shown, the cutting depth of the annular groove 30 is between 2 mm and 6 mm, and the ratio of the cutting depth of the annular groove 30 to the length of the main fire hole 20 is between 0.2 and 0.75.

[0038] See also Figures 2 to 7 As shown in FIGS. 9 and 11, a downwardly protruding stopper 111 is formed at the bottom of the outer wall 11. This structure is designed to cooperate with the flame distribution plate of the burner to prevent relative displacement between the fire cover body and the flame distribution plate.

[0039] See also Figure 2 As shown, the outer wall 11 is arranged opposite to the inner wall 12 of the fire cover body 1 and together with the top wall 13 of the fire cover body 1 encloses the gas mixing chamber 10. The top wall 13 extends inwardly and downwardly and protrudes from the inner wall 12 to form an energy-gathering edge 131.

[0040] See also Figures 8 to 11 As shown, the outer wall 11 is also provided with a flame stabilizing hole 40 and / or a flame stabilizing groove connected to the gas mixing chamber 10, and the flame stabilizing hole 40 and / or the flame stabilizing groove are located above and / or below the main fire hole 20, and the aperture of the flame stabilizing hole 40 is smaller than the aperture of the main fire hole 20 and / or the width of the flame stabilizing groove is smaller than the aperture of the main fire hole 20. Preferably, the flame stabilizing hole 40 and the flame stabilizing groove can be connected to the gas mixing chamber 10 respectively. Preferably, as in the prior art, the flame stabilizing hole 40 and the flame stabilizing groove can be "superimposed" on each other (that is, the two are connected to each other) and then connected to the gas mixing chamber 10. Through this structural design, it can further play the role of stabilizing the flame and increasing the firepower.

[0041] See also Fig.10 , 11 As shown, a plurality of main fire holes 20 are circumferentially distributed on the outer side wall 11, and the apertures of at least a portion of the main fire holes 20 are reduced and arranged at intervals to form a grate fire avoidance area A. Please note that "reduced" in this application means that the apertures of at least a portion of the main fire holes are smaller than the apertures of other main fire holes that have not changed. Preferably, the main fire holes located in the grate fire avoidance area A are arranged more densely.

[0042] Furthermore, a burner adopts the above-mentioned flame stabilizing cover for the burner.

[0043] Although the specific implementation modes of the present invention have been described above, those skilled in the art may modify the present invention without departing from the spirit and principle of the present invention. The protection scope of the present invention is defined by the claims and their equivalents.

Claims

1. A flame-stabilizing fire cap for a burner, comprising a fire cap body, the fire cap body having a gas mixing chamber opening downward, an outer wall of the fire cap body having a main fire hole communicating with the gas mixing chamber, an annular groove surrounding the outer wall being formed at the outlet of the main fire hole, Features: The annular groove cuts inwardly along the axial direction of the main fire hole, and the distance from the circumferential edge of the longitudinal section of the annular groove at one end near the entrance of the main fire hole to the axis of the main fire hole is smaller than the distance from the circumferential edge of the longitudinal section of the annular groove at one end located at the exit of the main fire hole to the axis of the main fire hole.

2. The flame stabilizing cap for a burner according to claim 1, Features: The width of the annular groove at the outlet of the main fire hole is smaller than the aperture of the main fire hole, so that the annular groove passes through the main fire hole.

3. The flame stabilizing cover for a burner according to claim 1 or 2, Features: The longitudinal cross section of the annular groove is one of a "convex" shape, a "{" shape, a handle shape, a pen tip shape, a triangle, and a trapezoid.

4. The flame stabilizing cap for a burner according to claim 1, Features: The angle between the axis direction of the main fire hole and the horizontal direction is 0 to 60 degrees.

5. The flame stabilizing cap for a burner according to claim 1, Features: The maximum width of the annular groove is between 0.5 mm and 1.8 mm.

6. The flame stabilizing cap for a burner according to claim 1, Features: The cutting depth of the annular groove is between 2 mm and 6 mm, and the ratio of the cutting depth of the annular groove to the length of the main fire hole is between 0.2 and 0.

75.

7. A flame stabilizing cover for a burner according to any one of claims 1, 2, 4 to 6, Features: The bottom end of the outer side wall is also formed with a limiting protrusion protruding downward.

8. The flame stabilizing cap for a burner according to claim 7, Features: The outer wall is arranged opposite to the inner wall of the fire cover body and together with the top wall of the fire cover body encloses the gas mixing chamber. The top wall extends obliquely inward and downward and protrudes from the inner wall to form an energy-gathering edge.

9. A flame stabilizing cap for a burner according to any one of claims 1, 2, 4 to 6, and 8, Features: The outer wall is also provided with a flame stabilizing hole and / or a flame stabilizing groove connected to the gas mixing chamber, and the flame stabilizing hole and / or the flame stabilizing groove are located above and / or below the main fire hole, and the aperture of the flame stabilizing hole is smaller than the aperture of the main fire hole and / or the width of the flame stabilizing groove is smaller than the aperture of the main fire hole.

10. A flame stabilizing cover for a burner according to any one of claims 1, 2, 4 to 6, and 8, Features: A plurality of main fire holes are circumferentially distributed on the outer side wall, and at least a portion of the main fire holes have reduced apertures and are arranged at intervals to form a furnace frame fire avoidance zone.

11. A burner, Features: A flame stabilizing cover for a burner as claimed in any one of claims 1 to 10 is used.

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