Fire grate, burner and water heater

Abstract

The invention discloses a fire grate, a combustor and a water heater, and relates to the technical field of water heaters, the fire grate comprises a fire grate body, the fire grate body is provided with a mixing cavity, a first air inlet flow channel and a second air inlet flow channel, the mixing cavity is provided with an air outlet, and the air inlet end of the first air inlet flow channel is provided with an injection opening used for introducing air and fuel gas; the exhaust end of the first air inlet flow channel is communicated with a mixing cavity, the air inlet end of the second air inlet flow channel is provided with an air inlet used for introducing air, the exhaust end of the second air inlet flow channel is communicated with the first air inlet flow channel, and the second air inlet flow channel is used for jetting flow to the first air inlet flow channel. A jet flow angle is formed between the jet flow direction of the second gas inlet flow channel and the gas conveying direction of the first gas inlet flow channel, and the jet flow angle is larger than 45 degrees and not larger than 70 degrees. And the combustion head part is arranged at the air outlet, and the combustion head part is provided with a fire hole communicated with the mixing cavity. According to the technical scheme provided by the invention, emission of carbon monoxide and nitrogen oxide can be reduced.

Description

Technical Field

[0001] This invention relates to the field of water heater technology, and in particular to a burner, a burner, and a water heater. Background Technology

[0002] Traditional burners often suffer from insufficient primary air intake and inadequate mixing of combustion gas and air inside the burner. This results in significant differences in combustion equivalence ratios at the burner outlet and poor flame uniformity, leading to increased emissions of carbon monoxide (CO) and nitrogen oxides (NOx). Summary of the Invention

[0003] The main objective of this invention is to provide a burner, a flame burner, and a water heater designed to reduce emissions of carbon monoxide and nitrogen oxides.

[0004] To achieve the above objectives, the present invention provides a fire extinguisher comprising: The burner body has a mixing chamber, a first air intake channel, and a second air intake channel. The mixing chamber has an outlet. The inlet end of the first air intake channel is provided with an injector for introducing air and fuel gas. The outlet end of the first air intake channel is connected to the mixing chamber. The inlet end of the second air intake channel is provided with an air intake for introducing air. The outlet end of the second air intake channel is connected to the first air intake channel. The second air intake channel is used to jet gas into the first air intake channel. The jetting direction of the second air intake channel forms a jetting angle with the gas delivery direction of the first air intake channel. The jetting angle is greater than 45° and not greater than 70°. A combustion head is disposed at the gas outlet, and the combustion head has a flame hole communicating with the mixing chamber.

[0005] In one embodiment, the second air intake channel has a jet section connected to the first air intake channel, and the cross-sectional area of ​​the jet section decreases from the air inlet toward the first air intake channel.

[0006] In one embodiment, the jet section includes a first wall and a second wall disposed opposite to each other along the extension direction of the first air intake channel. The first wall and / or the second wall are gradually inclined toward the side away from the ejector port along the jet direction of the second air intake channel, and the distance between the first wall and the second wall is gradually reduced along the jet direction of the second air intake channel.

[0007] In one embodiment, the first air intake channel has at least one ejector section extending from the ejector port toward the mixing chamber. The ejector section has a tapered section and a diffusing section arranged and connected along the airflow delivery direction. The flow cross-sectional area of ​​the tapered section decreases toward the diffusing section, and the flow cross-sectional area of ​​the diffusing section increases toward the direction away from the tapered section. The portion where the tapered section and the diffusing section meet forms the throat of the ejector section. The exhaust end of the second air intake channel is connected to at least one of the throats of the ejector section.

[0008] In one embodiment, the burner body has a first side and a second side opposite to each other along a first direction, and a third side and a fourth side opposite to each other along a second direction. The ejector port is located on the first side, the air inlet is located on the third side, and the air outlet is located on the fourth side. The first air inlet channel extends from the ejector port toward the second side, and the second air inlet channel extends from the air inlet toward the fourth side and is inclined toward a side away from the ejector port. The first direction is the length direction of the burner body, the second direction is the height direction of the burner body, and the air inlet is located on the bottom side of the burner body.

[0009] In one embodiment, the combustion head includes a flame distribution plate and a metal mesh. The flame distribution plate is provided with a plurality of flame holes, and the metal mesh is stacked on top of the flame distribution plate, with the metal mesh covering the plurality of flame holes.

[0010] In one embodiment, the metal mesh is stacked in three or four layers along its thickness direction; And / or, the mesh count of the metal mesh is not less than 30 mesh and not more than 40 mesh; And / or, the metal mesh is made of iron-chromium-aluminum.

[0011] In one embodiment, the fire distribution plate has a first plate surface disposed away from the mixing chamber, the sum of the total areas of the plurality of fire holes is defined as S1, the area of ​​the first plate surface is defined as S2, and the ratio of S1 to S2 is not less than 0.5 and not greater than 0.65.

[0012] In one embodiment, the flame distribution plate includes a plurality of combustion units spaced apart along the length of the flame plate body. Each combustion unit has a plurality of flame holes, and the plurality of flame holes of each combustion unit includes a first flame hole and a plurality of second flame holes. The first flame hole extends along the width of the flame plate body, and a plurality of second flame holes are respectively provided on both sides of the first flame hole along the length of the flame plate body. The plurality of second flame holes are spaced apart along the width of the flame plate body.

[0013] The present invention also proposes a burner comprising the fire bar as described above.

[0014] The present invention also proposes a water heater, including the burner described above.

[0015] The technical solution of this invention connects the ejector port, the first intake channel, the mixing chamber, and the flame hole in sequence, and the air inlet, the second intake channel, and the first intake channel in sequence. The jet direction of the second intake channel forms a jet angle with the intake direction of the first intake channel, which is greater than 45° and not greater than 70°. Air is supplied to the second intake channel through the air inlet, and the air is then obliquely jetted into the first intake channel through the second intake channel. This increases the primary air content in the first intake channel, improves the primary air coefficient, and suppresses the formation of thermal nitrogen oxides (NOx). Furthermore, the air jetted from the second intake channel forms a counter-mixing reaction with the combustion gas and air in the first intake channel, enhancing fluid turbulence within the first intake channel. This results in a more thorough and uniform mixing of air and combustion gas in the first intake channel, reducing carbon monoxide (CO) emissions from the flue gas. Furthermore, the air jet in the second intake duct has a component that moves away from the injector, preventing excessive resistance and back pressure on the air and fuel entering the first intake duct from the injector. This avoids fuel leakage caused by backflow from the injector in the first intake duct, ensuring safety. In this way, the primary air coefficient inside the burner is effectively increased, and the mixing of air and fuel is improved, effectively reducing emissions of carbon monoxide (CO) and nitrogen oxides (NOx). Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the structure of an embodiment of the fire briquette provided by the present invention; Figure 2 for Figure 1 A schematic diagram of the structure of the burner body of the center burner; Figure 3 for Figure 2 A schematic diagram of the airflow direction of the central burner body; Figure 4 This is a schematic diagram of the internal structure of the fire grill body; Figure 5 for Figure 1 A schematic diagram of the combustion head of the intermediate burner; Figure 6 for Figure 5Top view of the combustion head; Figure 7 for Figure 6 A magnified view of a section at point A in the middle; Figure 8 This is a schematic diagram of a burner embodiment provided by the present invention.

[0018] Explanation of icon numbers: 1000. Burner; 100. Flame purlin; 10. Flame purlin body; 101. Mixing chamber; 101a. Air outlet; 1011. First chamber section; 1012. Second chamber section; 102. First air intake channel; 102a. Ejector port; 1021. Ejector section; 1021a. Converging section; 1021b. Diverging section; 1021c. Throat; 10211. First ejector section; 10212. Second ejector section; 10213. Third ejector section; 103. Second Air intake channel; 103a, air intake port; 1031, jet section; 1031a, first wall surface; 1031b, second wall surface; 1032, inlet section; 10a, first side; 10b, second side; 10c, third side; 10d, fourth side; 20, combustion head; 20a, combustion unit; 21, flame distribution plate; 211, flame hole; 211a, first flame hole; 211b, second flame hole; 21a, first plate surface; 22, metal mesh.

[0019] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0022] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0023] Traditional burners often suffer from insufficient primary air intake and inadequate mixing of combustion gas and air inside the burner. This results in significant differences in combustion equivalence ratios at the burner outlet and poor flame uniformity, leading to increased emissions of carbon monoxide (CO) and nitrogen oxides (NOx).

[0024] This invention proposes a fire grill 100.

[0025] Please see Figures 1 to 3 In one embodiment of the present invention, the burner 100 includes a burner body 10 and a combustion head 20. The burner body 10 has a mixing chamber 101, a first air intake channel 102, and a second air intake channel 103. The mixing chamber 101 has an outlet 101a. The air intake end of the first air intake channel 102 is provided with an injection port 102a for introducing air and fuel gas. The exhaust end of the first air intake channel 102 is connected to the mixing chamber 101. The air intake end of the second air intake channel 103 is provided with an air intake port 103a for introducing air. The exhaust end of the second air intake channel 103 is connected to the first air intake channel 102. The second air intake channel 103 is used to jet gas into the first air intake channel 102. The jetting direction of the second air intake channel 103 and the gas conveying direction of the first air intake channel 102 form a jetting angle, which is greater than 45° and not greater than 70°. The combustion head 20 is located at the outlet 101a and has a flame hole 211 that communicates with the mixing chamber 101.

[0026] The burner body 10 constitutes the main support structure of the burner 100. The burner body 10 is hollow, forming a mixing chamber 101, a first air intake channel 102, a second air intake channel 103, an ejector port 102a, and an air inlet 103a. For ease of manufacturing, the burner body 10 can be constructed by joining two sheet metal parts together and fixing them by welding or riveting to ensure the reliable sealing of the internal flow channels. The ejector port 102a and the air inlet 103a can be located on the same side of the burner body 10, on adjacent sides of the burner body 10, or on opposite sides of the burner body 10. For example, when applied to a fan-driven water heater, the ejector port 102a can be located on one side of the burner body 10 along its length so as to communicate with the nozzle of the gas distribution device of the burner 1000. The air inlet 103a can be located on the bottom side of the burner body 10 so as to communicate with the air outlet of the fan below the burner 1000. The air outlet 101a of the mixing chamber 101 can be located on the top of the burner body 10, so that the flame holes 211 on the combustion head 20 face upwards.

[0027] The combustion head 20 has flame holes 211, and the number of flame holes 211 is usually multiple. These multiple flame holes 211 can be arranged at intervals along the length of the burner body 10. The ejector port 102a of the burner body 10 is connected to the mixing chamber 101 via the first air intake channel 102, and then the mixing chamber 101 is connected to the multiple flame holes 211 of the combustion head 20. The ejector port 102a is used to supply air and fuel gas to the first air intake channel 102, and the air and fuel gas are transported to the mixing chamber 101 for mixing via the first air intake channel 102, and then transported from the mixing chamber 101 to the flame holes 211 for ignition to produce a combustion flame. In practical applications, the nozzle of the gas distribution device of the burner 1000 can be used to inject fuel gas into the ejector port 102a, so that the fuel gas enters the first air intake channel 102. At the same time, external air can also enter the first air intake channel 102 through the ejector port 102a by self-priming or forced draft. Optionally, the first intake channel 102 is at least partially constructed as a Venturi channel, so that the high-speed flow of the gas in the first intake channel 102 generates a local low-pressure zone. The suction generated by the local low-pressure zone draws external air from the ejector port 102a into the first intake channel 102, and then delivers gas and air to the mixing chamber 101 through the first intake channel 102.

[0028] Understandably, the flow direction of the combustion gas and air in the first intake duct 102 is the same, making it difficult to form strong turbulence. This results in insufficient mixing of the combustion gas and air, and the relatively small amount of air introduced through the injector 102a of the first intake duct 102 leads to insufficient primary air content within the first intake duct 102, resulting in a low primary air coefficient inside the burner 100. The primary air coefficient is the ratio of the amount of combustion air pre-mixed with the combustion gas in the burner 1000 to the theoretically required amount of air. If the primary air coefficient is too low, it will lead to an increase in thermal nitrogen oxide (NOx) emissions.

[0029] To improve the mixing efficiency of fuel gas and air in the first intake air passage 102 and increase the primary air coefficient, the technical solution of this application also provides an air inlet 103a and a second intake air passage 103 in the burner body 10. The air inlet 103a is connected to the first intake air passage 102 via the second intake air passage 103. Thus, air can be supplied to the second intake air passage 103 through the air inlet 103a, and then supplied to the first intake air passage 102 from the second intake air passage 103, thereby increasing the primary air content in the first intake air passage 102 and improving the primary air coefficient. Furthermore, the second intake air passage 103 is used to jet gas into the first intake air passage 102. The jetting direction of the second intake air passage 103 forms a jetting angle with the gas delivery direction of the first intake air passage 102. The jetting direction of the second intake air passage 103 extends from the intake end towards the outlet end and is inclined towards the side away from the ejector port 102a. Thus, air can be obliquely jetted into the first intake channel 102 through the second intake channel 103. Since the jetting direction of the second intake channel 103 intersects with the gas transport direction in the first intake channel 102, the air jetted from the second intake channel 103 cross-jet with the gas and air in the first intake channel 102, forming a counter-current mixing, which enhances the fluid disturbance in the first intake channel 102, thereby making the mixing of air and gas in the first intake channel 102 more complete and uniform.

[0030] Furthermore, a jet angle α is formed between the jet direction of the second inlet air passage 103 and the gas delivery direction of the first inlet air passage 102. The jet angle α is greater than 45° and not greater than 70°, that is, 45° < α ≤ 70°. In this way, the jet angle is moderate. Specifically, the jet angle is no greater than 70° to ensure it is not too large, allowing the air jetted obliquely from the second intake channel 103 to have a component moving away from the ejector port 102a. This prevents excessive resistance and back pressure on the air and fuel entering the first intake channel 102 from the ejector port 102a, avoiding fuel leakage and ensuring safety. The jet angle is greater than 45° to ensure it is not too small, reducing pressure loss when air enters the second intake channel 103 through the intake port 103a. This allows the air in the second intake channel 103 to maintain a high velocity and jet towards the first intake channel 102, improving the mixing of air and fuel and ensuring thorough mixing. For example, the jet angle α can be 46°, 48°, 50°, 55°, 60°, 65°, 70°, or any angle within the aforementioned range.

[0031] The gas delivery direction of the first intake channel 102 refers to the flow direction of gas within the first intake channel 102. For example, the burner body 10 has a first side 10a and a second side 10b opposite each other along a first direction. An ejector port 102a is located on the first side 10a of the burner body 10. The first intake channel 102 extends from the ejector port 102a along the first direction toward the second side 10b of the burner body 10. When air and fuel gas enter the first intake channel 102 through the ejector port 102a, they flow along the first direction toward the second side. In this case, the gas delivery direction of the first intake channel 102 is from the first side toward the second side along the extension direction of the first intake channel 102, and the gas delivery direction of the first intake channel 102 is parallel to the central axis of the first intake channel 102. The jet direction of the second intake channel 103 refers to the direction of the airflow ejected from the second intake channel 103 toward the first intake channel 102. For example, if the second air intake channel 103 is connected to the first air intake channel 102 through the jet section 1031, then the jet direction of the second air intake channel 103 is parallel to the central axis of the jet section 1031.

[0032] Optionally, the air inlet 103a is connected to the air outlet of the fan, allowing air to be blown into the air inlet 103a by the fan. Compared to the scheme of using the local negative pressure generated by the first air intake channel 102 to draw external air from the air inlet 103a into the second air intake channel 103, using the fan to force air into the air inlet 103a can, on the one hand, increase the air intake volume and effectively increase the air volume inside the burner 100; on the other hand, the fan can generate greater wind pressure during operation, which is conducive to increasing the gas flow velocity from the air inlet 103a into the second air intake channel 103, and thus the second air intake channel 103 can jet air at high speed towards the first air intake channel 102, further improving the mixing effect of air and gas, and making the air and gas mix more thoroughly. For a fan-driven gas water heater, the fan is generally located at the bottom of the burner with the fan outlet facing upwards. In order to better introduce the air volume of the fan, the air inlet 103a can optionally be located on the bottom side of the burner body 10.

[0033] The burner 100 of the present invention includes a burner body 10 and a combustion head 20. The burner body 10 has a mixing chamber 101, a first air intake channel 102, a second air intake channel 103, an ejector port 102a, and an air inlet 103a. The combustion head 20 has a flame hole 211. The ejector port 102a, the first air intake channel 102, the mixing chamber 101, and the flame hole 211 are sequentially connected, and the air inlet 103a, the second air intake channel 103, and the first air intake channel 102 are sequentially connected. Thus, air and fuel gas are supplied to the first air intake channel 102 through the ejector port 102a, and the air and fuel gas are transported to the mixing chamber 101 through the first air intake channel 102 for mixing, and then transported from the mixing chamber 101 to the flame hole 211 for ignition to generate a combustion flame. Simultaneously, air is supplied to the second intake duct 103 through the air inlet 103a. This air is then obliquely jetted into the first intake duct 102 via the second intake duct 103, increasing the primary air content in the first intake duct 102, improving the primary air coefficient, and suppressing the formation of thermal nitrogen oxides (NOx). Furthermore, a jet angle is formed between the jet direction of the second intake duct 103 and the gas delivery direction of the first intake duct 102, with the jet angle being greater than 45° and not greater than 70°. This causes the air jetted from the second intake duct 103 to form a cross-jet with the combustion gas and air in the first intake duct 102, resulting in opposing mixing and enhanced fluid turbulence within the first intake duct 102. Consequently, the mixing of air and combustion gas within the first intake duct 102 is more thorough and uniform, reducing carbon monoxide (CO) emissions in the flue gas. Furthermore, the air jet in the second intake duct 103 has a component that moves away from the injector 102a, which prevents excessive resistance and back pressure on the air and fuel entering the first intake duct 102 from the injector 102a. This avoids fuel leakage caused by backflow from the injector 102a in the first intake duct 102, ensuring safety. In this way, the primary air coefficient inside the combustor 100 is effectively increased, and the mixing of air and fuel is improved, effectively reducing emissions of carbon monoxide (CO) and nitrogen oxides (NOx).

[0034] In order to further improve the jet effect, such as Figure 2 As shown, in one embodiment, the second air intake channel 103 has a jet section 1031 connected to the first air intake channel 102, and the cross-sectional area of ​​the jet section 1031 decreases from the air inlet 103a toward the first air intake channel 102.

[0035] In this embodiment, the cross-sectional area of ​​the jet section 1031 decreases from the air inlet 103a toward the first air intake channel 102. That is, the cross-sectional area of ​​the jet section 1031 near the air inlet 103a is relatively large, which helps reduce air resistance and increase the air intake. The cross-sectional area decreases towards the exhaust end of the jet section 1031. Since the cross-sectional area is smaller, the gas velocity is faster. Thus, the air is accelerated as it passes through the jet section 1031, allowing the second air intake channel 103 to jet air at high speed into the first air intake channel 102. This further enhances the mixing effect between air and fuel gas, resulting in a more thorough and uniform mixture and further reducing CO and NOx emissions from the flue gas. The cross-sectional area of ​​the jet section 1031 can decrease gradually from the air inlet 103a toward the first air intake channel 102, or decrease in a stepped manner. Optionally, the cross-sectional area of ​​the jet section 1031 is gradually reduced from the air inlet 103a toward the first air inlet channel 102. This makes the structure of the jet section 1031 simpler and does not cause excessive resistance to the airflow, which is more conducive to achieving high-speed jetting into the first air inlet channel 102.

[0036] Optionally, such as Figure 3 and Figure 4 As shown, the jet section 1031 includes a first wall surface 1031a and a second wall surface 1031b disposed opposite to each other along the extension direction of the first air intake channel 102. The first wall surface 1031a and / or the second wall surface 1031b are gradually inclined away from the ejector port 102a along the jet direction of the second air intake channel 103. The distance between the first wall surface 1031a and the second wall surface 1031b is gradually reduced along the jet direction of the second air intake channel 103.

[0037] For example, the first air intake channel 102 extends along a first direction (e.g., the length direction of the firebox body 10), and the jet section 1031 includes a first wall surface 1031a and a second wall surface 1031b disposed opposite each other along the first direction, wherein the first wall surface 1031a is located on the side of the second wall surface 1031b closer to the ejector port 102a. The first wall surface 1031a is gradually inclined away from the ejector port 102a along the jet direction, and the second wall surface 1031b is also gradually inclined away from the ejector port 102a along the jet direction. The first wall surface 1031a and the second wall surface 1031b have different inclination angles to ensure that the distance between the first wall surface 1031a and the second wall surface 1031b gradually decreases along the jet direction.

[0038] By gradually tilting the first wall surface 1031a and / or the second wall surface 1031b of the jet section 1031 away from the ejector port 102a along the jet direction of the second inlet channel 103, the distance between the first wall surface 1031a and the second wall surface 1031b gradually decreases along the jet direction of the second inlet channel 103. This causes the flow cross-sectional area of ​​the jet section 1031 to gradually decrease along the jet direction, thereby accelerating the jet. Furthermore, by setting the first wall surface 1031a and / or the second wall surface 1031b to gradually tilt away from the ejector port 102a along the jet direction, the airflow in the jet section 1031 can be guided, allowing the airflow to be injected into the first air intake channel 102 at an angle away from the ejector port 102a. This can improve the uniformity of air and gas mixing in the first air intake channel 102 and avoid excessive resistance to the gas in the first air intake channel 102, which would cause the gas to leak out from the ejector port 102a.

[0039] Optionally, the second air intake duct 103 further includes an inlet section 1032, through which the air inlet 103a connects to the jet section 1031. The central axis of the inlet section 1032 coincides with the central axis of the air inlet 103a. Air enters the inlet section 1032 through the air inlet 103a and is then transported to the jet section 1031, where it is jetted into the first air intake duct 102. By setting the inlet section 1032, it is ensured that the air inlet 103a can form a planar inlet on one side of the fire briquette body 10 (e.g., the bottom side of the fire briquette body 10). This facilitates the installation of the fire briquette with other planes and allows the air inlet 103a to be positioned opposite the air outlet of the fan. The inlet section 1032 can guide the airflow blown by the fan more smoothly into the jet section 1031, thereby reducing pressure loss and allowing the air in the jet section 1031 to maintain a high velocity and jet towards the first air intake duct 102. Optionally, the length of the inlet section 1032 is less than the length of the jet section 1031. This ensures that the length of the jet section 1031 of the second inlet channel 103 is sufficient, allowing the air to be fully accelerated within the jet section 1031 before being jetted at high speed into the first inlet channel 102, achieving high-speed collision mixing with the combustion gas and further improving the uniformity of the air-fuel mixture.

[0040] like Figure 2 and Figure 4As shown, in one embodiment, the first air intake channel 102 has at least one ejector section 1021 extending from the ejector port 102a toward the mixing chamber 101. The ejector section 1021 has a tapered section 1021a and a diffusing section 1021b arranged and connected along the airflow conveying direction. The flow cross-sectional area of ​​the tapered section 1021a decreases toward the diffusing section 1021b, and the flow cross-sectional area of ​​the diffusing section 1021b increases toward the direction away from the tapered section 1021a. The portion where the tapered section 1021a and the diffusing section 1021b meet forms the throat 1021c of the ejector section 1021. The exhaust end of the second air intake channel 103 is connected to at least one of the throats 1021c of the ejector section 1021.

[0041] The ejector section 1021 of the first inlet flow channel 102 is configured as a Venturi flow channel. The ejector section 1021 includes a tapering section 1021a, a diverging section 1021b, and a throat 1021c located between the tapering section 1021a and the diverging section 1021b. The throat 1021c can be the interface between the tapering section 1021a and the diverging section 1021b, or it can be a flow segment of a certain length. The number of ejector sections 1021 can be set according to the actual length of the flow channel; it can be one, two, or more sections.

[0042] It is understandable that when the flow cross-sectional area of ​​the converging section 1021a of the ejector section 1021 decreases from the ejector port 102a to the expanding section 1021b, a local negative pressure zone can gradually form near the end of the converging section 1021a as air and gas pass through it. This negative pressure actively draws the gas and air from the ejector port 102a, achieving efficient ejection and initial mixing. In addition, when the flow cross-sectional area of ​​the expanding section 1021b of the ejector section 1021 increases from the end near the converging section 1021a towards the mixing chamber 101, the flow velocity of the gas and air gradually decreases and the pressure gradually recovers as they pass through the expanding section 1021b. During this process, strong turbulence is formed, allowing the gas and air to fully penetrate and mix, further improving the mixing uniformity. In this way, when the first intake channel 102 delivers gas and air, the gas and air can be fully mixed, thereby improving the uniformity of the gas-air mixture when the first intake channel 102 is inlet.

[0043] Furthermore, the exhaust end of the second intake channel 103 is connected to at least one of the throats 1021c of the ejector section 1021, that is, the exhaust end of the second intake channel 103 is connected to the narrowing portion of the ejector section 1021. Since the pressure is lowest at the throat 1021c of the ejector section 1021, there is a large pressure difference between the air inlet 103a of the second intake channel 103 and the throat 1021c of the first intake channel 102, making it easier for external air to enter the first intake channel 102 through the second intake channel 103.

[0044] In practical applications, to ensure the jet flow rate of the second inlet channel 103, the connection port between the second inlet channel 103 and the first inlet channel 102 needs a certain opening area. However, the throat 1021c of the ejector section 1021 is usually small and insufficient to open a large connection port. Therefore, the connection port of the exhaust end of the second inlet channel 103 can be opened on the flow channel wall of the tapering section 1021a and / or the expanding section 1021b near the throat 1021c.

[0045] Optionally, multiple ejector sections 1021 are provided, and the multiple ejector sections 1021 are arranged and connected sequentially from the ejector port 102a to the mixing chamber 101.

[0046] It is understandable that, since the ejector section 1021 can accelerate the flow and decelerate the mixing of gas when conveying gas, when the first inlet flow channel 102 has multiple ejector sections 1021 arranged in sequence and connected, the airflow can undergo multiple acceleration-deceleration processes through the first inlet flow channel 102, so that the gas and air in the first inlet flow channel 102 can be mixed multiple times, thereby further improving the uniformity of gas and air mixing in the first inlet flow channel 102.

[0047] Optionally, such as Figure 2 As shown, the multiple ejector sections 1021 include a first ejector section 10211, a second ejector section 10212 and a third ejector section 10213, and the second air intake channel 103 is connected to the second ejector section 10212.

[0048] Understandably, since the first ejector section 10211 is directly connected to the ejector port 102a, it will directly draw in external air from the ejector port 102a and perform preliminary mixing with the combustion gas entering the first ejector section 10211. If the second intake channel 103 is connected to the expanding section 1021b of the first ejector section 10211, it may affect the air ejected from the first intake channel 102 and the preliminary mixing of air and combustion gas within the first intake channel 102. Furthermore, the third ejector section 10213 is directly connected to the mixing chamber 101. If the second intake channel 103 is connected to the expanding section 1021b of the third ejector section 10213, the air entering from the second intake channel 103 can only mix with the main airflow through this section and then directly enter the mixing chamber 101, which may result in poor mixing. Therefore, connecting the second intake channel 103 with the expanding section 1021b of the second ejector section 10212 can avoid affecting the air ejected by the first intake channel 102 and the initial mixing of the gas. At the same time, it can ensure that the air supplemented by the second intake channel 103 can be mixed again, ensuring that both the first intake channel 102 and the second intake channel 103 can work in an orderly manner.

[0049] Optionally, the mixing chamber 101 includes a first chamber section 1011 and a second chamber section 1012. The first chamber section 1011 and the second chamber section 1012 are arranged sequentially from the first air inlet channel 102 to the air outlet 101a. The flow cross-sectional area of ​​the first chamber section 1011 decreases from the first air inlet channel 102 to the second chamber section 1012, and the flow cross-sectional area of ​​the second chamber section 1012 increases from the second chamber section 1012 to the air outlet 101a.

[0050] This configuration allows the gas and air input from the first intake channel 102 to mix after passing through multiple ejector sections 1021, and the air input from the second intake channel 103 to mix with the gas input from the first intake channel 102 within the first intake channel 102. The gases input from both channels can then be accelerated through the first section 1011 of the mixing chamber 101 and decelerated through the second section 1012 of the mixing chamber 101, resulting in further mixing. This not only increases the air intake volume but also further enhances the uniformity of the air-gas mixture.

[0051] The volume of the mixing chamber 101 can be set to be greater than the sum of the volumes of the first inlet channel 102 and the second inlet channel 103. Furthermore, the volume of the second chamber section 1012 can be set to be greater than the volume of the first chamber section 1011. The mixed gas after secondary mixing in the mixing chamber 101 has sufficient diffusion space, and the gas flow rate can be reduced, thereby making the gas flow rate distribution delivered from the second chamber section 1012 to the outlet 101a more uniform.

[0052] like Figure 3As shown, in one embodiment, the ignition grid body 10 has a first side 10a and a second side 10b opposite to each other along a first direction, and a third side 10c and a fourth side 10d opposite to each other along a second direction. An ejector port 102a is located on the first side 10a, an air inlet 103a is located on the third side 10c, and an air outlet 101a is located on the fourth side 10d. A first air inlet channel 102 extends from the ejector port 102a toward the second side 10b, and a second air inlet channel 103 extends from the air inlet 103a toward the fourth side 10d and is inclined toward the side away from the ejector port 102a. The first direction is the length direction of the ignition grid body 10, the second direction is the height direction of the ignition grid body 10, and the air inlet 103a is located on the bottom side of the ignition grid body 10.

[0053] In this embodiment, the first side 10a and the second side 10b are opposite sides in the length direction of the fire duct body 10, and the third side 10c and the fourth side 10d are opposite sides in the height direction of the fire duct body 10. The third side 10c is the top side of the fire duct body 10, and the fourth side 10d is the bottom side of the fire duct body 10.

[0054] An ejector port 102a is provided on the first side 10a of the burner body 10. The first air intake channel 102 extends from the ejector port 102a along the length of the burner body 10 toward the second side 10b of the burner body 10. In this way, the length of the first air intake channel 102 can be extended as much as possible, which makes it easier to provide multiple ejector sections 1021 for the first air intake channel 102 to improve the uniformity of air and gas mixing.

[0055] An air inlet 103a is located on the third side 10c of the burner body 10 (i.e., the bottom side of the burner body 10). A second air inlet channel 103 extends from the air inlet 103a along the height of the burner body 10 towards the first air inlet channel 102 and is inclined away from the ejector port 102a. This arrangement, where the extension direction of the second air inlet channel 103 intersects with that of the first air inlet channel 102, facilitates cross-jetting of the gas and air through the second air inlet channel 103 towards the first air inlet channel 102, thereby improving the uniformity of gas and air mixing within the first air inlet channel 102. Furthermore, the jetting direction of the second air inlet channel 103 is deflected away from the ejector port 102a, preventing excessive resistance to the airflow at the ejector port 102a. This facilitates the smooth delivery of air and gas along the first air inlet channel 102 to the mixing chamber 101 and prevents gas leakage from the first air inlet channel 102 through the ejector port 102a.

[0056] For gas water heaters with bottom-mounted fans, the fan is generally located at the bottom of the burner 1000, with the flame of the burner 1000 facing upwards. By placing the air inlet 103a on the bottom side of the burner body 10, the fan outlet can face the air inlet 103a of the burner body 10, which is more conducive to directly blowing air into the air inlet 103a by the fan, increasing the primary air coefficient in the burner 100. Moreover, compared to the design of placing the air inlet 103a on the side of the burner body 10, placing the air inlet 103a on the bottom side of the burner body 10 makes it easier for the airflow generated by the fan to enter the burner body 10 through the air inlet 103a. Under the same air intake, the fan speed can be appropriately reduced, which helps to reduce fan noise and reduce the overall combustion noise of the unit.

[0057] The structure of the combustion head 20 is described below.

[0058] like Figure 5 As shown, in one embodiment, the combustion head 20 includes a flame distribution plate 21 and a metal mesh 22. The flame distribution plate 21 is provided with a plurality of flame holes 211. The metal mesh 22 is stacked with the flame distribution plate 21 and covers the plurality of flame holes 211.

[0059] It is understandable that when the metal mesh 22 covers multiple flame holes 211, the dense mesh structure of the metal mesh 22 can play the role of flame division. When the mixed gas is sprayed out from the multiple flame holes 211 on the flame distribution plate 21 and ignited, the flame spreads upward. The dense mesh of the metal mesh 22 divides the relatively concentrated flame into countless uniform and stable micro flames, thereby avoiding the flame from merging and forming local high temperature areas.

[0060] Meanwhile, the mesh openings of the metal mesh 22 can generate a certain flow resistance to the ejected airflow. The uniformly distributed resistance formed by the metal mesh 22 helps to balance the airflow velocity across the entire combustion surface, preventing the gas from being excessively concentrated in certain burner holes 211, thus avoiding excessively high local flame temperatures and allowing the flame to spread evenly on the surface of the metal mesh 22. This avoids concentrated flames and excessively high local flame temperatures during combustion, which would lead to the formation of large amounts of thermal nitrogen oxides.

[0061] Optionally, the metal mesh 22 is stacked in three or four layers along its thickness direction.

[0062] Understandably, if too many layers of metal mesh 22 are stacked, it will result in greater gas flow resistance. When the gas flows out of the burner holes 211, it will encounter greater flow resistance, affecting combustion. If fewer layers of metal mesh 22 are stacked, such as only one layer, the gas flow resistance will be smaller, making it difficult to ensure that the gas is evenly ejected from the burner holes 211. Therefore, three or four layers of metal mesh 22 are stacked to ensure moderate gas flow resistance and to ensure that the gas is evenly distributed to each burner hole 211, thereby ensuring a more uniform flame distribution during combustion.

[0063] Optionally, the mesh size of the metal mesh 22 is not less than 0.55 mm and not more than 0.6 mm. For example, the mesh size of the metal mesh 22 can be a square mesh, and the mesh size can be the width of the mesh. This setting can avoid the mesh size being too small, which would affect the smooth flow of gas, and also avoid the mesh size being too large, which would prevent the metal mesh 22 from uniformly separating the flame. For example, the mesh size can be 0.55 mm, 0.56 mm, 0.57 mm, 0.58 mm, 0.59 mm, 0.6 mm, and any point value within the range [0.55, 0.6].

[0064] Optionally, the wire diameter of the metal mesh 22 is not less than 0.22 mm and not more than 0.25 mm. This setting ensures that the metal mesh 22 has sufficient wire diameter, thereby providing sufficient structural strength and durability in high-temperature environments, and preventing damage and deformation due to prolonged heating. Simultaneously, sufficient metal content allows the metal mesh 22 to have better thermal conductivity, which is beneficial for uniform temperature distribution. For example, the wire diameter of the metal mesh 22 can be 0.22 mm, 0.23 mm, 0.24 mm, 0.25 mm, or any value within the range [0.22, 0.25].

[0065] Optionally, the mesh count of the metal mesh 22 is not less than 30 mesh and not more than 40 mesh. It can be understood that a mesh count between 30 and 40 meshes means there are 30 to 40 holes per inch of length. This roughly corresponds to a mesh aperture of approximately 0.425 mm to 0.595 mm. This configuration ensures that the mesh of the metal mesh 22 is dense enough to effectively divide the flame into uniform micro-flames, avoiding localized high temperatures, while also allowing sufficient airflow without causing excessive resistance to the flow of the gas mixture. This ensures that the firebox 100 has sufficient heat load output and prevents the flame from concentrating on a few larger fire holes 211, which could lead to excessively high combustion temperatures. For example, the mesh count of the metal mesh 22 can be 30, 32, 34, 36, 38, or 40 meshes.

[0066] Optionally, the metal mesh 22 is made of iron-chromium-aluminum alloy. It is understandable that iron-chromium-aluminum alloy has better high-temperature resistance, can withstand the high temperatures generated by combustion, and can prevent deformation under high-temperature combustion conditions, thus extending the service life of the metal mesh 22.

[0067] Optionally, the combustion head 20 is welded to the burner body 10 to ensure assembly reliability. The combustion head 20 may also include a connecting edge circumferentially disposed around the burner plate 21. The connecting edge may be integrally formed with the burner plate 21 and can be welded to the inner peripheral wall of the mixing chamber 101 to achieve welding fixation between the combustion head 20 and the burner body 10.

[0068] Optionally, the metal mesh 22 is welded to the fire distribution plate 21. Specifically, the metal mesh 22 and the fire distribution plate 21 can be fixed by welding, for example, by spot welding. Of course, other welding methods can also be used to fix the metal mesh 22 and the fire distribution plate 21; this is not limited here.

[0069] like Figure 6 As shown, in one embodiment, the fire distribution plate 21 has a first plate surface 21a disposed away from the mixing chamber 101. The total area of ​​the plurality of fire holes 211 is defined as S1, and the area of ​​the first plate surface 21a is defined as S2. The ratio of S1 to S2 is not less than 0.5 and not greater than 0.65.

[0070] The first plate surface 21a can be defined as the combustion surface of the flame distribution plate 21. When the ratio of the total area of ​​multiple flame holes 211 to the combustion surface is between 0.5 and 0.65, it avoids the situation where the total area of ​​the flame holes 211 occupies too little of the combustion surface area, resulting in excessively fast gas output velocity from each flame hole 211, leading to an excessively long flame that concentrates in a few flame holes 211, causing localized high temperatures and the generation of high-temperature nitrogen oxides. Conversely, it avoids the situation where the total area of ​​the flame holes 211 occupies too much of the combustion surface area, resulting in insufficient structural strength of the flame distribution plate 21 and potentially excessively dispersed flames, leading to insufficient combustion intensity. Therefore, setting the ratio of the total area of ​​multiple flame holes 211 to the combustion surface between 0.5 and 0.65 ensures that the gas flow rate and combustion uniformity are balanced, guaranteeing combustion intensity while preventing the generation of nitrogen oxides from localized high temperatures. For example, the ratio of S1 to S2 can be 0.5, 0.52, 0.55, 0.56, 0.58, 0.6, 0.62, 0.65, or any point value within the interval [0.5, 0.65].

[0071] The arrangement of the flame holes 211 on the flame distribution plate 21 is described below, such as... Figure 6 and Figure 7As shown, in one embodiment, the fire distribution plate 21 includes a plurality of combustion units 20a spaced apart along the length direction of the fire plate body 10. Each combustion unit 20a has a plurality of fire holes 211. The plurality of fire holes 211 of each combustion unit 20a includes a first fire hole 211a and a plurality of second fire holes 211b. The first fire hole 211a extends along the width direction of the fire plate body 10. A plurality of second fire holes 211b are respectively provided on both sides of the first fire hole 211a along the length direction of the fire plate body 10. The plurality of second fire holes 211b are spaced apart along the width direction of the fire plate body 10.

[0072] For example, such as Figure 7 As shown, each combustion unit 20a may include four second flame holes 211b. Two second flame holes 211b may be distributed on both sides of the first flame hole 211a of each combustion unit 20a. The two second flame holes 211b are spaced apart along the width direction of the firebox body 10. This arrangement ensures that each combustion unit 20a consists of a large strip-shaped flame hole 211 and two strip-shaped flame holes 211 on each side of the large strip-shaped flame hole 211. Within each combustion unit 20a, the first flame hole 211a can serve as a central anchor point, establishing a stable and continuous reference flame band. The multiple second flame holes 211b on both sides can serve as distribution points, dispersing the flame energy and forming a small, stable flame group, preventing excessive flame concentration at any point on a single combustion unit 20a.

[0073] Furthermore, by diverting the total gas flow rate within a combustion unit 20a through a large first burner hole 211a and multiple small auxiliary burner holes 211, the heat release is more dispersed and gentler compared to concentrating all the gas on a few points for combustion, thus fundamentally eliminating the conditions for generating local high-temperature zones.

[0074] Furthermore, the larger flame formed by the first fire hole 211a and the smaller flame formed by the second fire hole 211b restrain each other. The adjacent flames can preheat each other through thermal radiation and thermal conduction, stabilize each other, and form a stable combustion field, making the combustion on the entire fire distribution plate 21 more stable.

[0075] In addition to setting multiple combustion units 20a, the number of flame holes 211 located on both sides of the burner body 10 along its length can be increased. For example, the number of second flame holes 211b on both sides of the combustion units 20a can be increased, doubling the number of second flame holes 211b on both sides of the burner body 10 along its length, from two to four. This raises the ignition point and prevents the combustion temperature on both sides of the burner 100 from being too low due to insufficient gas supply. It also makes the temperature distribution of the entire combustion area along the length of the burner 100 more uniform, preventing excessively high temperatures in local combustion areas and the generation of thermal nitrogen oxides.

[0076] like Figure 8 As shown, the present invention also proposes a burner 1000, which includes a burner 100. The specific structure of the burner 100 is as described in the above embodiments. Since the burner 1000 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, and will not be described in detail here. The burner 1000 may include a frame and burners 100 disposed within the frame. Multiple burners 100 may be arranged side by side.

[0077] The present invention also proposes a water heater, including a burner 1000. The specific structure of the burner 1000 is as described in the above embodiments. Since this water heater adopts all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated upon here. The water heater includes, but is not limited to, a forced-draft gas water heater with a bottom-mounted fan, or a forced-extraction gas water heater with an top-mounted fan, etc.

[0078] For example, the burner 1000 can be applied to a forced-draft gas water heater with a bottom-mounted fan. The gas water heater includes a fan, burner 1000, heat exchanger, and fume hood arranged sequentially from bottom to top. The fan drives airflow from bottom to top, so that air enters into a single burner 100 of the burner 1000, or between two adjacent burners 100, to provide sufficient air for combustion in the burner 1000. Optionally, the air inlet 103a of the second air intake channel 103 of the burner 100 is located on the bottom side of the burner body 10, which is more conducive to blowing air directly into the air inlet 103a by the fan, increasing the primary air coefficient in the burner 100. Moreover, compared with the scheme of setting the air inlet 103a on the side of the burner body 10, setting the air inlet 103a on the bottom side of the burner body 10 makes it easier for the airflow generated by the fan to enter the burner body 10 through the air inlet 103a. Under the same air intake volume, the fan speed can be appropriately reduced, which is conducive to reducing fan noise and reducing the combustion noise of the whole machine.

[0079] The above description is merely an exemplary embodiment of the present invention and does not limit the scope of protection of the present invention. Any equivalent structural transformations made based on the technical concept of the present invention and the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present invention.

Claims

1. A fire grill, characterized in that, include: The burner body has a mixing chamber, a first air intake channel, and a second air intake channel. The mixing chamber has an outlet. The inlet end of the first air intake channel is provided with an injector for introducing air and fuel gas. The outlet end of the first air intake channel is connected to the mixing chamber. The inlet end of the second air intake channel is provided with an air intake for introducing air. The outlet end of the second air intake channel is connected to the first air intake channel. The second air intake channel is used to jet gas into the first air intake channel. The jetting direction of the second air intake channel forms a jetting angle with the gas delivery direction of the first air intake channel. The jetting angle is greater than 45° and not greater than 70°. A combustion head is disposed at the gas outlet, and the combustion head has a flame hole communicating with the mixing chamber.

2. The fire grill as described in claim 1, characterized in that, The second air intake channel has a jet section connected to the first air intake channel, and the cross-sectional area of ​​the jet section decreases from the air inlet toward the first air intake channel.

3. The fire grill as described in claim 2, characterized in that, The jet section includes a first wall and a second wall that are disposed opposite to each other along the extension direction of the first air intake channel. The first wall and / or the second wall are gradually inclined toward the side away from the ejector port along the jet direction of the second air intake channel. The distance between the first wall and the second wall is gradually reduced along the jet direction of the second air intake channel.

4. The fire grill as described in claim 1, characterized in that, The first air intake channel has at least one ejector section extending from the ejector port toward the mixing chamber. The ejector section has a tapered section and a diffusing section arranged and connected along the airflow delivery direction. The flow cross-sectional area of ​​the tapered section decreases toward the diffusing section, and the flow cross-sectional area of ​​the diffusing section increases toward the distance from the tapered section. The portion where the tapered section and the diffusing section meet forms the throat of the ejector section. The exhaust end of the second air intake channel is connected to at least one of the throats of the ejector sections.

5. The fire briquette as described in any one of claims 1 to 4, characterized in that, The fire briquette body has a first side and a second side opposite to each other along a first direction, and a third side and a fourth side opposite to each other along a second direction. The ejector port is located on the first side, the air inlet is located on the third side, and the air outlet is located on the fourth side. The first air inlet channel extends from the ejector port toward the second side, and the second air inlet channel extends from the air inlet toward the fourth side and is inclined toward the side away from the ejector port. The first direction is the length direction of the fire briquette body, the second direction is the height direction of the fire briquette body, and the air inlet is located on the bottom side of the fire briquette body.

6. The fire briquette as described in any one of claims 1 to 4, characterized in that, The combustion head includes a flame distribution plate and a metal mesh. The flame distribution plate has multiple flame holes, and the metal mesh is stacked on top of the flame distribution plate, covering the multiple flame holes.

7. The fire grill as described in claim 6, characterized in that, The metal mesh is stacked in three or four layers along its thickness direction; And / or, the mesh count of the metal mesh is not less than 30 mesh and not more than 40 mesh; And / or, the metal mesh is made of iron-chromium-aluminum.

8. The fire grill as described in claim 6, characterized in that, The fire distribution plate has a first plate surface disposed away from the mixing chamber. The total area of ​​the plurality of fire holes is defined as S1, and the area of ​​the first plate surface is defined as S2. The ratio of S1 to S2 is not less than 0.5 and not greater than 0.

65.

9. The fire grill as described in claim 6, characterized in that, The fire distribution plate includes a plurality of combustion units spaced apart along the length of the fire plate body. Each combustion unit has a plurality of fire holes. The plurality of fire holes in each combustion unit include a first fire hole and a plurality of second fire holes. The first fire hole extends along the width of the fire plate body. A plurality of second fire holes are respectively provided on both sides of the first fire hole along the length of the fire plate body. The plurality of second fire holes are spaced apart along the width of the fire plate body.

10. A burner, characterized in that, Includes the fire rack as described in any one of claims 1 to 9.

11. A water heater, characterized in that, Includes the burner as described in claim 10.

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