Adaptive premix burner

Abstract

The present invention relates to the field of commercial gas stoves, and in particular, to an adaptive premixing burner. The adaptive premixing burner comprises a premixing chamber, a first air duct, a second air duct, a gas duct and a combustion chamber; the first air duct and the gas duct are both connected to the premixing chamber; the premixing chamber is provided with a plurality of premixed gas outlets for discharging the premixed gas to the combustion chamber; the second air duct is connected to one end of the combustion chamber close to the premixing chamber. The structure of the present invention is simple, and only the gas feed amount needs to be adjusted. According to the heat load usage requirements, only the gas feed amount needs to be adjusted to achieve an adaptive ratio of air and gas, and the operation is simple and the universality is good.

Description

Technical Field

[0001] The invention relates to the field of commercial blast-type gas cookers, and in particular to an adaptive premix burner. Background Art

[0002] Currently, there are two main ways to control the premixing ratio of gas and air in the traditional blast premixed combustion system.

[0003] The first is that the gas heat load changes according to the usage demand. At the same time, the gas regulating valve is driven by the chain, gears, transmission shaft, connecting rod and other mechanical devices to change the air duct regulating valve to adjust the air volume to adapt to the reasonable air demand for gas combustion.

[0004] That is to say, the air supply and gas supply are controlled by two different valves, which are connected in a certain relationship through a series of structures, so that when one valve is adjusted, the other valve is adjusted accordingly. However, due to the difference in gas and air pressure, valve size and shape, etc., their linear changes are highly inconsistent, making it difficult to achieve a reasonable ratio of gas and air throughout the process, wasting energy and easily generating harmful gases, which in turn affects the environment. At the same time, the structure is complex, the failure rate is high, and the stability is poor.

[0005] The second method is to control the mixing ratio of gas and air through an electric proportional control valve. The specific working principle is that the gas heat load should change according to the demand. The wind speed and air volume are first adjusted through a variable speed blower, and then the change of negative pressure at different speeds at the air inlet end of the blower is used to control the intake of a corresponding amount of gas for premixing.

[0006] The second method, if it is to achieve a reasonable ratio of gas and air throughout the process, will also be restricted by factors such as the difference in gas and blast air pressure, system pipeline structure, etc., and it is also quite difficult to achieve and the system is complex, and has poor universality. Summary of the invention

[0007] The purpose of the present invention is to provide an adaptive premix burner which simplifies the structure and realizes adaptive proportioning of gas and air, thereby achieving a better combustion effect.

[0008] The embodiment of the present invention is achieved as follows:

[0009] An adaptive premixing burner comprises a premixing chamber, a first air conduit, a second air conduit, a gas conduit and a combustion chamber;

[0010] The first air conduit and the gas conduit are both in communication with the premixing chamber;

[0011] The premixing chamber is provided with a plurality of premixed gas outlets for discharging the premixed gas to the combustion chamber;

[0012] The second air conduit is communicated with one end of the combustion chamber close to the premixing chamber.

[0013] Preferably, the gas conduit is disposed in the first air conduit, and the axis of the outlet of the gas conduit is coaxial or parallel to the axis of the outlet of the first air conduit.

[0014] Preferably, the adaptive premixing burner further comprises an air inlet pipe, and an end of the first air duct away from the premixing chamber and an end of the second air duct away from the combustion chamber are both connected to the air inlet pipe.

[0015] Preferably, the axis of the air inlet pipe is perpendicular to the axis of the first air duct.

[0016] Preferably, the premixing chamber comprises a first mixing chamber and a second mixing chamber;

[0017] The first air conduit and the gas conduit are both communicated with the first mixing chamber, the first mixing chamber is communicated with the second mixing chamber, and the premixed gas outlet is arranged on the second mixing chamber.

[0018] Preferably, the inner cavity of the second mixing chamber is in the shape of a frustum of a cone, and the premixed gas outlet is arranged on the end face of the end with a larger area of ​​the frustum of the cone; the end face of the end with a smaller area of ​​the second mixing chamber is open, and the second mixing chamber is connected to the first mixing chamber through the open end.

[0019] Preferably, the premixing chamber further includes a premixing chamber, the first air conduit and the gas conduit are both in communication with the premixing chamber, and the premixing chamber is in communication with the first mixing chamber.

[0020] Preferably, the combustion chamber comprises a first combustion chamber and a second combustion chamber;

[0021] The first combustion chamber is connected to the premixing chamber through the premixed gas outlet, the second combustion chamber is connected to the first combustion chamber, and the second combustion chamber is arranged at one end of the first combustion chamber away from the premixing chamber;

[0022] The second air conduit is in communication with the first combustion chamber.

[0023] Preferably, the adaptive premix burner further comprises an air chamber, and the air chamber is arranged in an annular shape outside the first combustion chamber.

[0024] Preferably, the premixing chamber is cylindrical, and the inner tube wall of the first air duct is tangent to the inner side wall of the premixing chamber.

[0025] Preferably, the axis of the premixing chamber is perpendicular to the axis of the first air duct;

[0026] and / or,

[0027] The inner tube wall of the second air duct is tangent to the inner side wall of the air chamber.

[0028] The beneficial effects of the present invention are:

[0029] After the air and gas are mixed in the premixing chamber through the first air duct and the gas duct, the air and gas enter the combustion chamber through the premixing gas outlet for combustion. When the amount of gas passing through the gas duct is changed by the control valve, the expansion pressure generated by the combustion in the combustion chamber changes accordingly, and the inhibitory effect on the air in the air chamber entering the first combustion chamber through the air outlet will change accordingly, so that the amount of air entering the first combustion chamber through the air outlet of the air chamber changes accordingly, achieving the purpose of matching the corresponding air amount and participating in the combustion, and then forming a new balance under the action of various relevant new changing conditions, so that the gas can be fully burned. The structure of the present invention is simple. When the heat load needs to be changed, only the gas feed amount needs to be adjusted. The operation is simple and the universality is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 A schematic diagram of the structure of an adaptive premixed burner provided in an embodiment of the present invention;

[0032] Figure 2 for Figure 1 AA section view.

[0033] In the figure:

[0034] 1: air inlet pipe; 2: first air duct; 3: gas duct; 4: second air duct; 5: air chamber; 6: first mixing chamber; 7: sealing plate; 8: premixed gas outlet; 9: gas; 10: air; 11: mixed gas; 12: second mixing chamber; 13: premixed gas side outlet; 14: first combustion chamber; 15: second combustion chamber; 16: pilot burner; 17: air outlet; 18: pilot combustion chamber; 19: air inlet; 20: front mixing chamber. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0038] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0039] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0040] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] The following is combined with Figure 1 and attached Figure 2, some embodiments of the present invention are described in detail. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0042] An adaptive premixing burner comprises a premixing chamber, a first air duct 2, a second air duct 4, a gas duct 3 and a combustion chamber; the first air duct 2 and the gas duct 3 are both connected to the premixing chamber; a plurality of premixed gas outlets 8 are provided on the premixing chamber for discharging the premixed gas to the combustion chamber; the second air duct 4 is connected to one end of the combustion chamber close to the premixing chamber.

[0043] Specifically, in the present embodiment, only the front section of the gas conduit 3 is provided with a control valve, through which the flame during combustion is controlled, that is, the combustion heat load is controlled, and a reasonable ratio of gas and air that is relatively ideal throughout the entire process of design heat load usage change can be obtained, making the structure simple and easy to control.

[0044] Starting from closing, the control valve on the front section of the gas pipeline of the gas conduit 3 is opened to the minimum fire combustion state, that is, the state of the designed minimum stable combustion heat load. At this time, the flame is burning in the first combustion chamber 14, and each part is balanced under the action of positive and reverse forces. Next, the opening degree is increased by the control valve to increase the gas flow rate. In the process, a new rebalance is achieved dynamically in real time through various action mechanisms until it reaches the maximum.

[0045] More specifically, in this embodiment, the premixed gas outlet 8 is disposed on the sealing plate 7, and the sealing plate 7 is used to seal the premixing chamber.

[0046] Preferably, the gas conduit 3 is disposed in the first air conduit 2 , and the axis of the outlet of the gas conduit 3 is coaxial or parallel to the axis of the outlet of the first air conduit 2 .

[0047] Specifically, in this embodiment, the gas conduit 3 and the first air conduit 2 are coaxially arranged, the outlet of the gas conduit 3 is at the axial end of the gas conduit 3 , and the outlet of the first air conduit 2 is at the axial end of the first air conduit 2 .

[0048] The specific operating principle is as follows: the air from the first air duct 2 and the gas from the gas duct 3 are first mixed in the premixing chamber, and then discharged through the premixed gas outlet 8 and the premixed gas side outlet 13, and then contacted with the pilot flame generated by the pilot flame burner 16. When the mixed gas discharge reaches the minimum design heat load, it is ignited by the pilot flame. At this time, the gas volume and the air volume achieve a relatively reasonable ratio and reach a dynamic balance under the conditions of design pressure, resistance and caliber so that the flame can burn fully and stably. The ignited flame burns sufficiently and stably in the first combustion chamber and generates a certain flame expansion pressure. This expansion pressure has a certain inhibitory effect on the entry of the air in the air chamber 5 into the first combustion chamber 14 through the air outlet 17 of the air chamber 5, and on the entry of the mixed gas in the second mixing chamber into the first combustion chamber 14 through the premixed gas outlet 8. When the gas flow through the gas duct 3 is gradually increased through the control valve, the increase in the corresponding proportion of the blast air volume is achieved through the combined action of the following four action mechanisms:

[0049] (a) If Figure 1 As shown, since the gas conduit 3 and the first air conduit 2 are coaxially arranged, and the gas conduit 3 is arranged in the first air conduit 2, the airflow direction in the gas conduit 3 is in the same direction as the airflow direction in the first air conduit 2, and the gas outlet end of the gas conduit 3 is arranged at the position of the front premixing chamber 20, that is, the end closer to the premixing chamber. The airflow entering the first air conduit 2 from the air inlet 19 first passes through the first air conduit 2 for a distance, and is guided by the first air conduit 2. When it reaches the position of the outlet end of the gas conduit 3, it achieves the purpose of being coaxial and in the same direction with the gas airflow. Then, the gas with a certain pressure and the blast air with a certain pressure form a mutual induced action relationship, and form a dynamic balance under the conditions of their respective pressures, resistances and calibers. The increase in the amount of gas passing through the gas outlet end under the same caliber must be the result of an increase in the flow rate of the gas airflow. Due to the mutual induced effect, the increase in the flow rate of the gas airflow must break the original balance, so that the induced effect of the gas on the air is relatively enhanced, thereby allowing more air to enter, achieving the purpose of increasing the amount of air and participating in combustion, and then forming a new balance under the action of various related new changing conditions.

[0050] (ii) Under the minimum design heat load state, the flame burning in the first combustion chamber will generate a certain flame expansion pressure. This expansion pressure has a certain inhibitory effect on the air in the first combustion chamber 5 when it enters the first combustion chamber 14 through the air outlet 17 of the air chamber 5, and forms a dynamic balance. Of course, when the gas volume gradually increases, if the air cannot be increased to a reasonable proportion, then the flame burning in the first combustion chamber at this time will cause incomplete combustion due to lack of oxygen. The incomplete combustion caused by lack of oxygen will cause the combustion expansion pressure of the flame to decrease accordingly, which is commonly known as soft fire. As a result, the inhibitory effect on the air in the air chamber 5 when it enters the first combustion chamber 14 through the air outlet 17 will be reduced accordingly, so that the amount of air entering the first combustion chamber 14 through the air outlet 17 of the air chamber 5 will increase accordingly, thereby achieving the purpose of increasing the amount of air and participating in combustion, and then forming a new balance under the action of various relevant new changing conditions.

[0051] (III) Under the minimum design heat load state, the flame burning in the first combustion chamber will generate a certain flame expansion pressure. This expansion pressure will have a certain inhibitory effect on the entry of the mixed gas into the second mixing chamber through the premixed gas outlet 8 and form a dynamic balance. Of course, when the gas volume gradually increases, if the air cannot be increased to a reasonable proportion, then the flame burning in the first combustion chamber will be insufficiently burned due to lack of oxygen. The insufficient combustion caused by lack of oxygen will reduce the combustion expansion pressure of the flame accordingly, commonly known as soft fire, and the inhibitory effect on the entry of the mixed gas into the premixed gas outlet 8 will be reduced accordingly, and the original balance will be destroyed. Then, through the gas conduction in the premixed combustion chamber, the dynamic balance inhibitory effect on the gas outlet end on the gas duct 3 and the air inlet end on the first air duct 2 will also be reduced accordingly. Furthermore, through gas conduction, the dynamic balance inhibitory effect on the gas and air source ends will also be reduced accordingly. Before the new balance is established, the reduction in this inhibitory effect will dynamically cause the outlet end of the gas duct 3 to be compressed. The amount of gas entering the premixing chamber is further increased, and at the same time, the amount of air entering the premixing chamber through the first air duct 2 is also dynamically increased. From a safety perspective, in the gas and air supply system of the blast-type gas cooker, the gas source pressure of the gas is often higher than the gas source pressure of the blast air to avoid the risk of flashback explosion caused by air backflowing into the gas pipeline. Therefore, since the gas pressure is higher than the blast air pressure, the sensitivity of air entry to the change of the same reverse inhibition effect is higher than the sensitivity of gas entry to the change of the same reverse inhibition effect, so that in addition to the increase in gas volume caused by the change of the valve, the increase in gas and air entry due to the reduction of the reverse inhibition effect, the increase in air entry will be more on the basis of the reasonable combustion ratio of gas and air. For example, the reasonable ratio of natural gas to air combustion is 1:10, and the ratio of the increase in entry due to the reduction of the inhibition effect may be 1:13. The extra air will participate in compensating for the corresponding reasonable proportion of air required to increase the amount of gas due to the adjustment of the valve. Therefore, the purpose of increasing the amount of air and participating in combustion is achieved, and then a new balance is formed under the action of various relevant new changing conditions.

[0052] (IV) When the amount of gas passing through the gas duct 3 is gradually increased through the control valve, the flame that was originally fully and stably burning in the first combustion chamber at the minimum design heat load state will gradually rise in the main combustion zone of the flame and transition to the second combustion chamber due to the increase in the amount of gas. As the main fire position gradually rises, the regional pressure position in the combustion chamber changes, and the reverse suppression pressure on the air outlet 17 of the air chamber 5 will decrease accordingly, causing the amount of air entering the first combustion chamber 14 through the air outlet 17 to increase, thereby achieving the purpose of increasing the amount of air and participating in combustion, and then forming a new balance under the action of various relevant new changing conditions.

[0053] In this embodiment, the adaptive premixing burner further comprises an air inlet pipe 1 , and an end of a first air duct 2 away from the premixing chamber and an end of a second air duct 4 away from the combustion chamber are both connected to the air inlet pipe 1 .

[0054] Specifically, in this embodiment, the axis of the air inlet pipe 1 is perpendicular to the axis of the first air duct 2 .

[0055] The air inlet 19 of the first air duct 2 is arranged on the side wall of the first air duct 2, and the axis of the air inlet 19 is coaxial with the axis of the air inlet pipe 1, so that after passing through the air inlet pipe 1, the air enters the first air duct 2 facing the air inlet 19.

[0056] Preferably, the premixing chamber includes a first mixing chamber 6 and a second mixing chamber 12; the first air duct 2 and the gas duct 3 are coaxially arranged and both are connected to the first mixing chamber 6, the first mixing chamber 6 is connected to the second mixing chamber 12, and the premixed gas outlet 8 is connected to the second mixing chamber 12.

[0057] Through the two premixing steps, the fuel gas 9 and the air 10 are mixed more fully.

[0058] Specifically, in the present embodiment, the first mixing chamber 6 is outside the second mixing chamber 12, and / or the first mixing chamber 6 is below the second mixing chamber 12. After the gas 9 and the air 10 are mixed through the first mixing chamber 6, the mixed gas 11 enters the second mixing chamber 12 for mixing again, so that after two mixings, the gas 9 and the air 10 are mixed more evenly, thereby ensuring that the gas 9 can be fully burned.

[0059] Preferably, the second mixing chamber 12 has an outer shape of a truncated cone, and the premixed gas outlet 8 is arranged on the end surface of the truncated cone with a larger area.

[0060] In this embodiment, the second mixing chamber 12 is configured in a truncated cone shape, and the second mixing chamber 12 is entirely configured in the first mixing chamber 6, with the small end face of the second mixing chamber 12 at the bottom and the large end face at the top, and the connection position between the second mixing chamber 12 and the first mixing chamber 6 is at the small end face. At this time, the mixed gas 11 in the first mixing chamber 6 first passes through the lower end of the second mixing chamber 12, and then enters the second mixing chamber 12, and undergoes a space compression and expansion, a change in the gas flow direction, and an extension of the gas flow return path, so that the gas is further mixed, and the mixed gas after the change in direction can flow out more evenly through the premixed gas outlet 8.

[0061] Specifically, the second mixing chamber 12 is separated from the first combustion chamber 14 by a sealing plate 7 , and the premixed gas outlet 8 is on the sealing plate 7 , connecting the second mixing chamber 12 with the first combustion chamber 14 .

[0062] It can be seen from the above that in this embodiment, the mixing of air and fuel gas is carried out in three ways: first, mixing on the path; second, mixing by changing the direction of the airflow; third, obtaining the desired uniform upward airflow so that each air outlet can emit air evenly; and fourth, mixing by space compression and expansion.

[0063] It should be pointed out that, in the present embodiment, the outer shape of the second mixing chamber 12 can be set to a frustum, or it can be set to other shapes, such as a cylinder, a square column, etc., as long as it can achieve secondary mixing of the mixed gas 11 in terms of distance and direction.

[0064] In this embodiment, a premixed gas side outlet 13 directly connected to the combustion chamber is provided on the inner side of the upper end of the first mixing chamber 6, and its function is to utilize the relatively low-temperature premixed gas flow flowing in the first mixing chamber 6 to effectively dissipate heat from the entire inner wall of the first combustion chamber 14, because the first combustion chamber 14 itself is also a part of the overall structure of the burner, and good heat dissipation is conducive to a long service life, and the second combustion chamber 15 is relatively independent of the overall structure of the burner, and can be used as an easily replaceable consumable part, and does not affect the overall service life of the burner. Another function of the premixed gas side outlet 13 is to make the burning fire more concentrated into a bundle, and can also correspondingly avoid the high-position flame from eroding the inner walls of the first combustion chamber 14 and the second combustion chamber 15, and at the same time, the relatively concentrated flame also meets the proper characteristics of commercial blast-type gas cookers.

[0065] Preferably, the premixing chamber further includes a premixing chamber 20 , the first air conduit 2 and the gas conduit 3 are both in communication with the premixing chamber 20 , and the premixing chamber 20 is in communication with the first mixing chamber 6 .

[0066] Specifically, in the present embodiment, the gas conduit 3 is disposed in the first air conduit 2, the end of the gas conduit 3 is completely contained by the first air conduit 2, and a pre-mixing chamber 20 is formed inside the outlet end of the first air conduit 2, so that the gas output from the gas conduit 3 is first mixed with the air in the first air conduit 2, and then enters the first mixing chamber 6 for more thorough mixing.

[0067] Preferably, the combustion chamber includes a first combustion chamber 14 and a second combustion chamber 15; the first combustion chamber 14 is connected to the premixing chamber through the premixed gas outlet 8 and the premixed gas side outlet 13, the second combustion chamber 15 is connected to the first combustion chamber 14, and the second combustion chamber 15 is arranged at an end of the first combustion chamber 14 away from the premixing chamber; the second air duct 4 is connected to the first combustion chamber 14 through the air chamber 5.

[0068] Specifically, in this embodiment, the second combustion chamber 15 is above the first combustion chamber 14, the second air duct 4 is connected to the side wall of the first combustion chamber 14 through the air chamber 5, and the opening end of the long-fire combustion chamber 18 of the long-fire burner 16 is inside the first combustion chamber 14.

[0069] More specifically, in this embodiment, the second combustion chamber 15 is in the shape of a truncated cone structure, with the end with a larger area connected to the first combustion chamber 14 and the end with a smaller area at the top. Such a configuration can ensure the stability of the flame and the concentration of the flame temperature, thereby improving the performance and efficiency of the burner.

[0070] Preferably, the premixing chamber is cylindrical, and the inner tube wall of the first air duct 2 is tangent to the inner side wall of the premixing chamber.

[0071] The inner wall of the first air duct 2 is tangent to the inner wall of the premixing chamber, so that the air 10 entrained with the gas 9 spirals into the premixing chamber through the first air duct 2, which is equivalent to increasing the travel of the air 10 entrained with the gas 9 in the premixing chamber.

[0072] Similarly, in this embodiment, the inner wall of the gas conduit 3 is also tangent to the inner wall of the premixing chamber, so that when the gas 9 enters the premixing chamber, the travel distance of the gas 9 in the premixing chamber can be increased.

[0073] The increase in the travel distance of the gas 9 and the air 10 in the premixing chamber enables the gas 9 and the air 10 to be fully mixed, thereby making the combustion more complete and ensuring the combustion efficiency.

[0074] Preferably, the axis of the premixing chamber is perpendicular to the axis of the first air duct 2 .

[0075] It should be pointed out that the axis of the premixing chamber and the axis of the first air duct 2 may be perpendicular or non-perpendicular, as long as the travel of the air 10 in the premixing chamber can be increased to ensure uniform mixing of the gas 9 and the air 10.

[0076] Preferably, the adaptive premix burner further comprises an air chamber 5, which is annularly arranged outside the combustion chamber.

[0077] Specifically, in this embodiment, the inner tube wall of the second air duct 4 is tangent to the inner side wall of the air chamber 5 .

[0078] It can be seen from the above that the working principle and working process of the adaptive premixed burner of the present invention are as follows:

[0079] The gas 9 with a certain gas source pressure enters the gas conduit 3, and enters the premixing chamber through the gas conduit 3. The air 10 delivered by the blower passes through the air inlet pipe 1, and a part of it enters the first air conduit 2 through the air inlet 19, and enters the premixing chamber through the first air conduit 2, and a part of it directly enters the air chamber 5 through the second air conduit 4. The gas conduit 3, the first air conduit 2 and the gas conduit 3 are all arranged tangent to the circular premixing chamber, so that the gas 9 and the air 10 entering the circular premixing chamber can be fully and effectively mixed. The second air conduit 4 is arranged tangent to the circular secondary air chamber 5, so that the pressure of the air 10 entering the air chamber 5 is equal at the air outlet 17 close to the circular distribution. The gas conduit 3 is coaxially placed in the first air conduit 2, and the outlet end of the gas conduit 3 is placed on the side of the first air conduit 2 close to the premixing chamber and at a position not entering the premixing chamber, that is, at the position of the pre-premixing chamber 20, so that the gas 9 coming out of the gas conduit 3 can contact and mix with the air 10 in the first air conduit 2 and then enter the premixing chamber together. The air inlet 19 of the first air conduit 2 is placed at a position that is concentric with the axial direction of the air inlet pipe 1, that is, the axis of the first air conduit 2 is perpendicular to the axis of the air inlet pipe 1, so as to facilitate the stability of the amount of air entering the first air conduit 2.

[0080] During the use of commercial stoves, operators will change the size of the heat load, that is, the firepower adjustment, at any time according to different needs. Therefore, the burner of the commercial stove must have a maximum heat load and a minimum stable combustion heat load when it is designed, such as a maximum heat load of 35 kilowatts, a minimum stable combustion heat load of 8 kilowatts, and other target limits. The gas heat load of the burner of the present invention can still be controlled by the traditional method with a flow-limiting nozzle at the front end to limit the maximum heat load, and the gas volume can be controlled by a control valve such as a ball valve and a plug valve to achieve the change adjustment and shutdown of the heat load, and the matching of the reasonable amount of air 10 corresponding to different heat load changes within the upper and lower limits of the heat load is achieved by an adaptive method.

[0081] The specific process is that, first, referring to the target value of the minimum stable combustion heat load, combined with the test, the size of the opening of the air inlet on the first air duct 2 is set to ensure that the system air 10 is matched with the minimum stable combustion heat load state. A certain amount of air 10 entering the first air duct 2 contacts the gas 9 coming out of the outlet end of the gas duct 3 in the first air duct 2 in a forward direction, and enters the circular premixing chamber together in a tangential direction, rotates along the inner wall in the premixing chamber for premixing, and then enters the second premixing chamber through the lower end of the conical second premixing chamber for further full premixing. The mixed gas enters the first combustion chamber 14 through the premixed gas outlet 8 and the premixed gas side outlet, and after encountering the pilot flame source of the pilot flame burner 16, it starts to burn in the primary combustion chamber. If the opening position of the control valve is at the opening position of the minimum stable combustion heat load at this time, the flame will burn stably and sufficiently in the first combustion chamber 14 at the designed minimum heat load. At this time, the gas volume is controlled by the control valve, and the air volume is controlled by the opening of the air inlet on the first air duct 2 with a reasonable flow rate.

[0082] Since the combustion flame at this time is mainly concentrated in the first combustion chamber 14 and the combustion is sufficient, a regional combustion expansion pressure will be formed around the fully burned flame. This regional combustion expansion pressure is mainly concentrated in the first combustion chamber 14. This pressure will form a reverse inhibition effect on the overflow of the mixed gas 11 in the premixing chamber through the premixed gas outlet 8 and the premixed gas side outlet 13. This effect will be reversely transmitted to the gas conduit 3 and the first air conduit 2. Since the supply pressure of the gas 9 is much higher than the supply pressure of the air 10 of the blower, the object of this inhibition is mainly reflected in the air 10 entering from the first air conduit 2. In addition, the expansion pressure of the combustion flame will also have a relatively large reverse inhibition effect on the air 10 overflowing from the outlet of the second air conduit 4, specifically, the air outlet 17 of the air chamber 5. That is, the sufficient combustion of the gas 9 and the air 10 under the reasonable ratio at this time is based on the dynamic equilibrium state of the combustion expansion pressure, the gas pressure, the mixed gas 11 pressure, and the secondary air pressure.

[0083] Under the minimum stable combustion heat load state, as the opening degree of the control valve gradually increases, the previous dynamic balance is gradually destroyed. In theory, this will inevitably lead to an increase in the amount of gas and a relatively insufficient amount of air. The insufficient amount of air will lead to incomplete combustion, but at the same time, this incomplete combustion will also lead to a sharp drop in the regional combustion expansion pressure. This drop in pressure will correspondingly cause the reverse inhibition effect that mainly acted on the outlets of the first air duct 2 and the second air duct to drop sharply, which will correspondingly lead to an increase in the amount of air under the blast pressure that overflows from the outlet of the first air duct 2 and the air outlet 17 of the air chamber 5. The increase in the amount of air will eliminate the increase in the amount of gas. Insufficient air volume causes incomplete combustion. At the same time, as the heat load increases, the demand for combustion expansion space by the combustion flame also increases. This will inevitably cause the position of the combustion flame in the primary combustion chamber to gradually move upward toward the direction of the second combustion chamber 15. At the same time, the regional combustion expansion pressure center also gradually moves upward and away from the premixed gas outlet 8, the premixed gas side outlet 13, the air outlet 17 of the air chamber 5, etc. At this time, the increase in air volume caused by insufficient combustion and reduced regional expansion pressure is transformed into an upward movement of the regional combustion expansion pressure center, so that the reverse inhibition of air 10 can be sustained and stable, avoiding the occurrence of surge and achieving real-time dynamic rebalancing. As the heat load of the fuel gas 9 continues to increase, the action mechanism is the same until the designed maximum heat load is reached, and the heat load of the fuel gas 9 is reversely adjusted until the designed minimum stable combustion heat load, and the action mechanism is the same in the opposite direction.

[0084] The beneficial effects of the embodiments of the present invention are:

[0085] After the air and gas are mixed in the premixing chamber through the first air duct and the gas duct, the air and gas enter the combustion chamber through the premixing gas outlet for combustion. When the amount of gas passing through the gas duct is changed by the control valve, the expansion pressure generated by the combustion in the combustion chamber changes accordingly, and the inhibitory effect on the air in the air chamber entering the first combustion chamber through the air outlet will change accordingly, so that the amount of air entering the first combustion chamber through the air outlet of the air chamber changes accordingly, achieving the purpose of matching the corresponding air amount and participating in the combustion, and then forming a new balance under the action of various relevant new changing conditions, so that the gas can be fully burned. The structure of the present invention is simple. When the heat load needs to be changed, only the gas feed amount needs to be adjusted. The operation is simple and the universality is good.

[0086] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An adaptive premix burner, characterized in that: It includes a premixing chamber, a first air conduit, a second air conduit, a gas conduit and a combustion chamber; The first air conduit and the gas conduit are both in communication with the premixing chamber; The premixing chamber is provided with a plurality of premixed gas outlets for discharging the premixed gas to the combustion chamber; The second air conduit is in communication with an end of the combustion chamber close to the premixing chamber; The gas conduit is arranged in the first air conduit, and the axis of the outlet of the gas conduit is coaxial or parallel to the axis of the outlet of the first air conduit; The combustion chamber comprises a first combustion chamber and a second combustion chamber; The first combustion chamber is connected to the premixing chamber through the premixed gas outlet, the second combustion chamber is connected to the first combustion chamber, and the second combustion chamber is arranged at one end of the first combustion chamber away from the premixing chamber; The second air conduit is in communication with the first combustion chamber; It also includes an air chamber, which is arranged in an annular shape outside the first combustion chamber; The premixing chamber is cylindrical, and the inner tube wall of the first air duct is tangent to the inner side wall of the premixing chamber; The axis of the premixing chamber is perpendicular to the axis of the first air duct; and / or, The inner tube wall of the second air duct is tangent to the inner side wall of the air chamber.

2. The adaptive premix burner according to claim 1, characterized in that: It also includes an air inlet pipe, and one end of the first air conduit away from the premixing chamber and one end of the second air conduit away from the combustion chamber are both connected to the air inlet pipe.

3. The adaptive premix burner according to claim 2, characterized in that: The axis of the air inlet pipe is perpendicular to the axis of the first air duct.

4. The adaptive premix burner according to claim 1, characterized in that: The premixing chamber includes a first mixing chamber and a second mixing chamber; The first air conduit and the gas conduit are both communicated with the first mixing chamber, the first mixing chamber is communicated with the second mixing chamber, and the premixed gas outlet is arranged on the second mixing chamber.

5. The adaptive premix burner according to claim 4, characterized in that: The inner cavity of the second mixing chamber is in the shape of a frustum, and the premixed gas outlet is arranged on the end face of the frustum with a larger area; the end face of the second mixing chamber with a smaller area is open, and the second mixing chamber is connected to the first mixing chamber through the open end.

6. The adaptive premix burner according to claim 4, characterized in that: The premixing chamber further includes a premixing chamber, the first air conduit and the gas conduit are both in communication with the premixing chamber, and the premixing chamber is in communication with the first mixing chamber.

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