CN110274227B

CN110274227B - Combustion air supply circular plate and combustor system thereof

Info

Publication number: CN110274227B
Application number: CN201910433531.2A
Authority: CN
Inventors: 吕志鸿; 王东杰; 刘海涛; 胡煦东; 靳雁松; 贾川; 贾大鹏; 李源浩
Original assignee: China North Vehicle Research Institute
Current assignee: China North Vehicle Research Institute
Priority date: 2017-05-22
Filing date: 2017-05-22
Publication date: 2021-03-16
Anticipated expiration: 2037-05-22
Also published as: CN107246610B; CN107246610A; CN110260304B; CN110274227A; CN110260304A

Abstract

The invention provides a combustion air supply circular plate and a burner system thereof, wherein the combustion air supply circular plate comprises a central vent hole and a circumferential vent hole, and the circumferential vent hole is of a fan-shaped structure taking the center of the central vent hole as the center of a circle; the circumferential vent holes are asymmetrically distributed. According to the invention, through the arrangement of the shapes, positions and angles of the central vent hole and the circumferential vent hole, the fuel oil and air can be promoted to be fully mixed in the premixing ignition chamber, the contact area of the air and the fuel oil is increased at the initial stage of the movement of atomized fuel oil, the combustion speed of the fuel oil is improved, the pressure in a diffusion combustion stage is reduced, the requirement on the axial length of the combustor is favorably reduced, and the volume of the combustor is reduced.

Description

Combustion air supply circular plate and combustor system thereof

Technical Field

The invention belongs to the technical field of combustion, and particularly relates to a burner for an auxiliary starting heater of a power transmission device.

Background

The power transmission system of the special vehicle is subject to adverse factors such as friction pair locking, poor lubrication, reduction of the power supply capacity of a storage battery, difficulty in engine ignition in a low-pressure environment and the like in an extremely cold environment, and the reliability of the vehicle is greatly reduced. The warmer is used as a combustion heat exchange device, heat is transferred through cooling liquid, and a cooling system, a lubricating system, a transmission system, a power system and the like of a vehicle can be warmed under an extreme environment, so that each system reaches an optimal working state, and adverse factors faced by vehicle starting are eliminated. Meanwhile, the light weight of the vehicle and the adaptability to various extreme environmental conditions put forward the requirements of high power density, high integration, high efficiency, low consumption and high adaptability to the heater.

The existing warmer generally faces the problems of low combustion efficiency and power density and serious carbon deposition, and the most key link of the warmer technology is the combustion device which can meet the requirements of stable, efficient and rapid combustion. The combustion of the warmer is a complex physical and chemical process, and the influencing factors comprise the geometric size and shape of a combustion chamber, the turbulence intensity and scale of a combustion flow field, the existence of a vortex reverse flow region, the oil-injection atomization position and taper, the distribution of air-fuel ratio in the flow field, the turbulence diffusion mixing speed and the like. Based on the background technology and experimental research, the invention provides a premixed ignition and diffusion combustor system.

Disclosure of Invention

The invention provides a mounting base of a premixed ignition and diffusion combustor and a combustor thereof, which are applied to an atomized fuel high-pressure ignition type heater and have the characteristics of high combustion efficiency and volume power, reliable ignition, suitability for various extreme environments and high heat utilization rate.

The technical scheme is as follows: the utility model provides a diffusion combustion chamber, the diffusion combustion chamber is including a transition section of thick bamboo, a secondary air inlet section of thick bamboo, cubic air inlet transition ring, the one end of a secondary air inlet section of thick bamboo is connected to a transition section of thick bamboo rear end, and the first end of cubic air inlet transition ring is connected to the other end of a secondary air inlet section of thick bamboo, set up the fresh air inlet on the transition section of thick bamboo, a secondary air inlet section of thick bamboo sets up the fresh air inlet, cubic air inlet transition ring sets up the air.

Preferably, the transition cylinder of the diffusion combustion chamber is in a conical ring shape, and a plurality of round holes are uniformly distributed on the circumference of the transition cylinder and used as a main gas supply channel of diffusion combustion.

Preferably, two ends of the secondary air inlet cylinder of the diffusion combustion chamber are designed to be open, one end of the secondary air inlet cylinder is connected with the large-diameter end of the transition cylinder to form a diffusion combustion space, and the other end of the secondary air inlet cylinder is connected with the large-diameter end of the tertiary air inlet transition ring to be used as a diffusion combustion exhaust channel.

Preferably, a plurality of guide pipes are uniformly distributed on the outer wall of the secondary air inlet cylinder of the diffusion combustion chamber and used for secondary air inlet of the diffusion combustion chamber.

Preferably, the secondary air intake cylinder is provided with a plurality of rows of air intake holes, the length of the secondary air intake cylinder is L, the distance from the inlet of the secondary air intake cylinder is X, the inner diameter of the air intake holes is D, and D ═ F₁(X) satisfying the following requirements:

D’>0,0<＝X<L/2；

D’<0,L/2<＝X<＝L。

d' is the first derivative of D.

Preferably, along transition section of thick bamboo to cubic air inlet transition ring direction, the internal diameter of fresh air inlet is along cubic air inlet transition ring entry to cubic air inlet transition ring middle range of increase bigger and bigger, and the range that constantly reduces from cubic air inlet transition ring middle to cubic air inlet transition ring export is bigger and bigger, satisfies following requirement:

D”>0,0<＝X<L/2；

D”>0,L/2<＝X<＝L。

d "is the second derivative of D.

Preferably, a plurality of round holes are uniformly formed in the middle height of the small-diameter column ring of the tertiary air inlet transition ring of the diffusion combustion chamber, and a plurality of through holes are formed in the circumferential direction of the large-diameter transition thin plate and are respectively used for fuel oil combustion at the end of the diffusion combustion without being exhausted and the organization and fuel oil combustion of the internal flow field of the diffusion combustion chamber.

The utility model provides a combustor system, includes combustor urceolus, air feed installation base, mixes ignition chamber and diffusion combustion chamber in advance, mix ignition chamber and diffusion combustion ware in advance and set up in the combustor urceolus, and air feed installation base, mix ignition chamber and diffusion combustion chamber in advance connect gradually, and the first end of combustor urceolus is connected on the outer wall of installing support mix ignition chamber one end connection center vent in advance, diffusion combustion chamber end connection waste gas flue, the diffusion combustion chamber is preceding the diffusion combustion chamber.

As preferred, the heat transfer core sets up in the waste gas flue, the heat transfer core includes pipe and flat pipe, the flow direction of liquid all hangs down to the flow direction of waste gas in pipe and the flat pipe, along the flow direction of waste gas, distributes pipe and flat pipe in proper order.

Preferably, a plurality of dispersed heat exchange structures are arranged in the circular tube in a segmented manner, each dispersed heat exchange structure comprises a core body and a shell, the core body is arranged in the shell, the shell is fixedly connected with the inner wall of the heat exchange tube, the core body comprises a plurality of grid pieces which are arranged and combined, and grid holes are formed by connecting the grid pieces; along the flowing direction of fluid in the circular tube, a plurality of dispersed heat exchange structures are arranged in the circular tube, and the length of each dispersed heat exchange structure is longer and longer from the inlet of the circular tube to the outlet of the circular tube;

the length of the dispersing heat exchange structure is increased from the inlet of the circular tube to the outlet of the circular tube.

Compared with the prior art, the invention has the following advantages:

1) the invention provides a premixed ignition and diffusion combustor, which comprises an air supply installation base, a premixed ignition chamber, a diffusion combustion chamber and a combustor outer cylinder, wherein the four components are concentrically and serially welded to form a combustor whole. The atomized fuel oil outlet is parallel to the swirl generating plate of the premixing combustion chamber, part of air enters the premixing ignition chamber through the swirl channel, and the air flowing in a rotating mode and the atomized fuel oil are fully mixed near the oil nozzle to form fuel oil-gas mixed gas which is used as a fire source for ignition and combustion of the combustor, so that reliable ignition is guaranteed. The air entering the premixing combustion chamber from the lower-layer air hole of the shunting device has a blocking effect on the oil-gas mixture, and forms the oil-gas mixture with fuel oil as much as possible, so that the phenomenon of flame extinction after the ignition process is finished is avoided, the premixing mixture is provided for the diffusion combustion stage, the working pressure of the diffusion combustion stage is reduced, a stable flame source of the combustor is formed, and the propagation of flame and the improvement of the combustion efficiency are facilitated.

2) The diffusion combustion chamber transition cylinder is designed into an outer conical ring, the diameter of the outer conical ring is gradually increased, the contact area of fuel oil and air is increased in order to match with a large-cone-angle fuel spray nozzle and the organization of a combustion flow field, the probability that the fuel oil is attached to a wall surface is reduced, meanwhile, a plurality of round holes are formed in the circumferential direction of the transition cylinder, airflow is guided to flow to the central area of the combustion chamber, the air content near the unburned fuel oil in the flame is increased, and the combustion rate of the fuel oil is improved.

3) A plurality of cylindrical guide pipes are circumferentially arranged near the axial height of the secondary air inlet cylinder 1/2 of the diffusion combustion chamber, partial air entering the diffusion combustion air inlet channel enters the combustion chamber through the guide pipes at a high speed, ejected fuel oil and flame are lifted in the upper space, the axial moving speed is reduced, the residence time of the secondary air inlet cylinder in the combustion chamber is prolonged, and the sufficient combustion of the fuel oil is facilitated.

4) A plurality of backflow through holes are formed in the circumferential direction of a large-diameter transition thin plate of a tertiary air inlet transition ring of a diffusion combustion chamber, part of air entering a diffusion combustion air inlet channel flows upwards through the through holes, an air barrier is formed between ejected fuel and the wall of the combustion chamber, the fuel is prevented from being attached to the wall of the combustion chamber to form carbon deposition, meanwhile, the air flow is guided by a conical annular transition cylinder in the rising process of the air flow and interacts with air entering a circumferential air inlet hole of the transition cylinder to form tumble flow in the central area of the combustion chamber, the mixing degree of the fuel and the air is increased, the combustion efficiency and the combustion speed of the fuel are improved, the axial length required by the sufficient combustion of the fuel.

5) A plurality of round holes are uniformly formed in the middle height of a small-diameter column ring of a tertiary air inlet transition ring of the diffusion combustion chamber, part of air entering a diffusion combustion air inlet channel enters the tail end of the combustion chamber through the round holes, the movement speed of flame is reduced, and the air and a small part of fuel which is not burnt out in the flame are mixed and combusted, so that the combustion efficiency of the fuel is improved.

6) The waste heat exchange device is arranged in the waste gas flue, the heat exchange core body is a circular tube-flat tube combined heat exchange structure, the front end of the heat exchange core body adopts a thin-wall circular tube heat exchange structure, the rear end of the heat exchange core body adopts a plurality of rows of thin-wall flat tube heat exchange structures, and different heat exchange structures are adopted at different positions according to different heat absorption capacities, so that the film boiling phenomenon at the water side is effectively reduced, the heat load of the heat exchange core body is reduced, and the heat exchange efficiency is improved.

7) According to the heat exchange device, the heat exchange core body adopts the round tube-shaped heat exchange tube, the diameter of the heat exchange tube is gradually reduced along the flow direction of flue gas, the film boiling phenomenon at the water side can be effectively reduced, the convective heat exchange strength at the water side is increased, the heat load of the heat exchange core body is reduced, and the heat exchange efficiency is improved.

8) According to the heat exchange device, the distance between the dispersed heat exchange structures in the circular tube is continuously reduced along with the distance from the inlet of the circular tube, so that the film boiling phenomenon of the water side can be effectively reduced, the convective heat exchange strength of the water side is increased, the heat load of the heat exchange core is reduced, and the heat exchange efficiency is improved.

9) According to the heat exchange device, the length of the dispersed heat exchange structure in the circular tube is continuously reduced along with the distance from the inlet of the circular tube, so that the film boiling phenomenon of the water side can be effectively reduced, the convective heat exchange strength of the water side is increased, the heat load of the heat exchange core is reduced, and the heat exchange efficiency is improved.

10) According to the heat exchange device, the grid type dispersed heat exchange structure is arranged in the heat exchange tube, so that a steam-water mixture in the heat exchange tube is separated, the film boiling phenomenon on the water side is effectively reduced, the convective heat exchange strength on the water side is increased, the heat load of the heat exchange core is reduced, and the heat exchange efficiency is improved.

Drawings

FIG. 1 is a front view of an embodiment of a premixed ignition, diffusion combustor of the present invention;

FIG. 2 is a left side view of the premixed ignition, diffusion combustor of FIG. 1;

FIG. 3 is a front view of a premix ignition chamber cyclone generation plate of the present invention;

FIG. 4 is a cross-sectional view of a premixed ignition chamber cyclone generation plate of the present invention;

FIG. 5 is a front view of a three-layer intake transition ring for a diffusion combustor of the present invention.

FIG. 6 is a top view of a three-layer air intake transition ring for a diffusion combustor of the present invention.

FIG. 7 is a schematic view of the internal structure of the air supply mounting base of the present invention;

FIG. 8 is a schematic view of the external structure of the wind supply mounting base of the present invention;

FIG. 9 is a front view of an embodiment of the waste heat utilizing heat exchange device of the present invention;

FIG. 10 is a water side structure view of a heat exchange core of the waste heat utilization heat exchange device;

FIG. 11 is a gas side structure view of a heat exchange core of the waste heat utilization heat exchange device;

FIG. 12 is a schematic cross-sectional structure diagram of a dispersed heat exchange structure of the waste heat utilization heat exchange device;

FIG. 13 is a schematic diagram of the arrangement of the dispersed heat exchange structure of the waste heat utilization heat exchange device in the heat exchange tube;

fig. 14 is another schematic diagram of the arrangement of the heat-dispersing heat exchange structure of the waste heat utilization heat exchange device in the heat exchange tube.

In the figure: 1. mounting a bracket; positioning a boss 1-1; a flange 1-2; 2. a combustion air supply circular plate; 2-1 central vent; 2-2 circumferential vent holes; 3. a swirl generating plate; 3-1 central hole; 3-2, a rotational flow channel; 3-3 of bulges; 4. a flow divider; 5. a sleeve; 6. a transition cylinder; 7. a secondary air intake cylinder; 8. a tertiary air inlet transition ring; 9. a combustion chamber outer cylinder; 10. premixing air outlet holes; 11. premixing air inlet holes; 12. a main air supply hole; 13. a flow guide pipe; 14. a return orifice; 15. three layers of air inlet holes; 16. a flow dividing channel; 17 flues, 18 heat exchange cores, 19 front supports, 20 rear supports, 21 upper cover plates, 22 lower cover plates, 23 inlet headers, 24 outlet headers, 25 middle parts, 26 round pipes, 27 water outlet pipes, 28 separation heat exchange structures, 29 shells, 30 grid sheets, 31 grid holes, 32 flat pipes, 33 fins, 34 exhaust ports, 35 exhaust ports and 36 inner fins.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings.

As shown in fig. 1, the burner comprises a burner outer cylinder, an air supply installation base, a premixed ignition chamber and a diffusion combustion chamber, wherein the air supply installation base, the premixed ignition chamber and the diffusion combustor are sequentially connected in series, and the premixed ignition chamber and the diffusion combustor are arranged in the burner outer cylinder.

Preferably, the air supply installation base comprises an installation support 1 and a combustion air supply circular plate 2, the first end of the installation support 1 is open, the second end of the installation support is provided with the combustion air supply circular plate 2, the center of the combustion air supply circular plate 2 is provided with a central vent hole 2-1, a circumferential vent hole 2-2 is circumferentially arranged around the central vent hole 2-1, the first end of the pre-mixing ignition chamber is connected with the central vent hole 2-1, the second end of the pre-mixing ignition chamber is connected with the diffusion combustion chamber, the pre-mixing ignition chamber comprises a rotational flow generation plate 3, a flow distribution device 4 and a sleeve 5, the flow distribution device 4 and the sleeve 5 are arranged in concentric circles, the rotational flow generation plate 3 is arranged in the flow distribution device 4, a flow distribution flow passage 16 is formed between the flow distribution device 4 and the sleeve 3, the sleeve 3 extends to the central vent hole 2-1, a premixing air outlet 10 and a premixing air inlet 11 are arranged on the pipe wall of the flow dividing flow passage 16, the premixing air outlet 10 is arranged between the rotational flow generating plate 3 and the central air vent (namely, arranged at the front end of the rotational flow generating plate 3), and the premixing air inlet 11 is arranged between the rotational flow generating plate 3 and the diffusion combustion chamber; the diffusion combustion chamber includes a transition section of thick bamboo 6, a secondary air inlet section of thick bamboo 7, cubic air inlet transition ring 8, the outer wall of diverging device 4 is connected to 6 one end of a transition section of thick bamboo, and the one end of a secondary air inlet section of thick bamboo 7 is connected to the other end, and the first end of cubic air inlet transition ring 8 is connected to the other end of a secondary air inlet section of thick bamboo 7, set up fresh air inlet 12 on the transition section of thick bamboo 6, a secondary air inlet section of thick bamboo 7 sets up fresh air inlet 13, cubic air inlet transition ring 8 sets up air intake 15, 9 first ends of combustor urceolus are connected on the outer wall of installing support 1, and the second.

The invention provides a premixed ignition and diffusion combustor, which comprises an air supply installation base, a premixed ignition chamber, a diffusion combustion chamber and a combustor outer cylinder, wherein the four components are concentrically and serially welded to form a combustor whole. The atomized fuel oil outlet is parallel to the swirl generating plate of the premixing combustion chamber, part of air enters the premixing ignition chamber through the swirl channel, and the air flowing in a rotating mode and the atomized fuel oil are fully mixed near the oil nozzle to form fuel oil-gas mixed gas which is used as a fire source for ignition and combustion of the combustor, so that reliable ignition is guaranteed. The air entering the premixing combustion chamber from the lower-layer air hole of the shunting device has a blocking effect on the oil-gas mixture, and forms the oil-gas mixture with fuel oil as much as possible, so that the phenomenon of flame extinction after the ignition process is finished is avoided, the premixing mixture is provided for the diffusion combustion stage, the working pressure of the diffusion combustion stage is reduced, a stable flame source of the combustor is formed, and the propagation of flame and the improvement of the combustion efficiency are facilitated.

Preferably, the mounting bracket 1 is provided with a combustor positioning boss 1-1 to realize the mounting and positioning of the combustor.

Preferably, the mounting bracket 1 is a stepped cylinder with gradually changed diameter, the first end surface is provided with a mounting flange 1-2 for axial positioning of the combustor, and the outer side surface is provided with a mounting and fixing boss 1-1 for circumferential positioning of the combustor.

Preferably, the mounting bracket 1 has a stepped shape inside, and gradually shrinks from the first end to the second end. Thereby forming a high-efficiency and quick air inlet effect.

Preferably, the mounting bracket 1 has three steps, which are a first step, a second step and a third step from the first end to the second end, wherein the three steps are in tapered transition, and the inner diameters of the three steps are sequentially: 190mm for 180-

Further preferably, the inner diameters of the three steps are as follows: 186mm, 163mm, 138 mm.

Through above-mentioned preferred size, further improve the air inlet effect.

Preferably, the fixing boss 1-1 is installed on the second step.

The invention can effectively improve the flow speed of air entering the combustor, enhance the movement intensity of the air in the premixing ignition chamber and the diffusion combustion chamber and increase the contact area of the air and the combustion by setting the three-stage steps and optimizing the sizes of the three-stage steps.

Preferably, the total area ratio of the central vent holes to the peripheral vent holes is (3.5-4.5): 1; preferably, 3.7: 1.

Preferably, the circumferential vent hole 2-2 of the combustion air supply circular plate 2 is of a fan-shaped structure taking the center of the central vent hole 2-1 as the center of a circle.

Preferably, the circumferential ventilation holes 2-2 are asymmetrically distributed.

Preferably, 8 circumferential vent holes 2-2 are provided. 8 individual circumference ventilation hole 2-2 is asymmetric distribution, and specific distribution is: the area of the circumferential vent hole 2-2 at the lowermost portion is larger than that of the circumferential vent holes 2-2 at other positions.

Preferably, the central angles of the 7 fan rings at other positions are the same, and the corresponding spacing angles of the other 7 adjacent fan ring edges are the same.

More preferably, the central angle of the adjacent 7 fan rings is the same as the corresponding spacing angle of the adjacent fan ring edge, and is respectively 19 degrees and 26 degrees, the central angle of the other fan ring is 23.5 degrees, and the spacing angle between the other fan ring and the adjacent fan ring is 17 degrees and 30.5 degrees.

Through the shape, position and the setting of angle of above-mentioned center ventilation hole and circumference ventilation hole, can promote just intensive mixing of fuel and air in premixing ignition chamber, increase the area of contact of air and fuel at atomizing fuel motion initial stage, improve the burning rate of fuel, reduce the pressure in diffusion combustion stage, be favorable to reducing combustor axial length demand, reduce the combustor volume.

Preferably, the center of the rotational flow generating plate 3 is provided with a circular hole 3-1 which is used as an atomized fuel inlet, and the circumferential direction of the rotational flow generating plate is provided with a rotational flow channel 3-2 which is used as an inlet of combustion air.

Preferably, the swirl passage 3-2 is formed by slotting 3-2 on the swirl generation plate. The slit extends to the circular hole 3-1. It is further preferred that one side 3-3 of the slot 3-2 be turned outward (in the direction of the first end of the premixed ignition chamber) to form a swirl passage. Further preferably, the tilted side 3-3 is a bending structure, and the bending angle of the bending structure is preferably an obtuse angle. Preferably 100-. Preferably, the inflection points 3-4 are closer to the outer diameter of the swirl imparting plate. Preferably, the bending point 3-4 is spaced from the inner diameter of the swirl flow generation plate 3 by 8 to 10 times, preferably 9 times, the distance from the outer diameter.

Preferably, the distance between the front end surface of the rotational flow generating plate and the plane where the circle center of the upper premixed air outlet is located is 6 mm.

Preferably, one side 3-3 of the slot 3-2 forms a triangle with the other side 3-5 of the slot. The corresponding internal angle of the cross section triangle of the cyclone channel is 6 degrees and 65 degrees. The included angle between the tilted side 3-3 and the rotational flow generating plate is 17 degrees.

Preferably, the pre-mixing air inlet holes 11 on the flow dividing device 4 are of a cylindrical structure and extend towards the inside of the flow dividing device 4.

Preferably, the height of the columnar structure is 3 mm.

Preferably, a plurality of raised rotational flow channels 3-2 are circumferentially arranged by taking the central hole of the rotational flow generating plate 3 as a reference, the cross section of each channel is triangular, and the height of the cross section is gradually increased along the direction far away from the center of the rotational flow plate.

According to the invention, by adopting the premixing ignition chamber with a novel structure, the atomized fuel oil inlet is parallel to the swirl generation plate of the premixing combustion chamber, part of air enters the premixing ignition chamber through the swirl channel, and the air which flows in a rotating manner is fully mixed with the atomized fuel oil near the oil nozzle to form fuel oil-gas mixed gas which is used as a fire source for ignition and combustion of the combustor, so that reliable ignition is ensured.

Preferably, the diffusion combustion chamber transition cylinder 6 is in a conical ring shape, and the small-diameter end of the diffusion combustion chamber transition cylinder is connected with the outlet of the premixed ignition chamber and is used as an inlet of premixed combustion flame and diffusion combustion fuel.

Preferably, a plurality of circular holes 12 are uniformly distributed on the periphery of the transition cylinder 6 and are used as main gas supply channels for diffusion combustion.

The diffusion combustion chamber transition cylinder is designed into an outer conical ring, the diameter of the outer conical ring is gradually increased, the contact area of fuel oil and air is increased in order to match with a large-cone-angle fuel spray nozzle and the organization of a combustion flow field, the probability that the fuel oil is attached to a wall surface is reduced, meanwhile, a plurality of round holes are formed in the circumferential direction of the transition cylinder, airflow is guided to flow to the central area of the combustion chamber, the air content near the unburned fuel oil in the flame is increased, and the combustion rate of the fuel oil is improved.

Preferably, two ends of the secondary air inlet cylinder 7 of the diffusion combustion chamber are designed to be open, one end of the secondary air inlet cylinder is connected with the large-diameter end of the transition cylinder 6 to form a diffusion combustion space, and the other end of the secondary air inlet cylinder is connected with the large-diameter end of the tertiary air inlet transition ring 8 to be used as a diffusion combustion exhaust channel.

Preferably, a plurality of guide pipes 13 are uniformly distributed on the outer wall of the secondary air inlet cylinder 7 of the diffusion combustion chamber and used for secondary air inlet of the diffusion combustion chamber.

Preferably, the draft tube 13 is disposed at the 1/2 axial height plane of the secondary air intake cylinder 7.

A plurality of air inlet holes are circumferentially formed near the axial height of the secondary air inlet cylinder 1/2 of the diffusion combustion chamber, partial air entering the diffusion combustion air inlet channel enters the combustion chamber through the guide pipe at a high speed, ejected fuel oil and flame are lifted in the upper space, the axial moving speed is reduced, the residence time of the secondary air inlet cylinder in the combustion chamber is prolonged, and the sufficient combustion of the fuel oil is facilitated.

Preferably, the secondary air intake cylinder 7 is provided with a plurality of rows of air intake holes 13. The inner diameter of the air inlet hole is increased and then reduced along the direction from the transition cylinder 6 to the tertiary air inlet transition ring 8.

The length of the secondary air inlet cylinder 7 is L, the distance from the inlet of the secondary air inlet cylinder 7 is X, the inner diameter of the air inlet hole is D, and D is F₁(X) satisfying the following requirements:

D’>0,0<＝X<L/2；

D’<0,L/2<＝X<＝L。

d' is the first derivative of D.

Through the change of the inner diameter of the air inlet 13, the flow of the combustion-supporting air is changed along the axial rule according to the combustion condition of the fuel in the secondary air inlet cylinder 7, so that the combustion efficiency of the combustor can reach the best.

Through experimental discovery, through so setting up, can further improve combustion efficiency.

Further preferably, along transition section of thick bamboo 6 to the 8 directions of cubic air inlet transition ring, the internal diameter of fresh air inlet is along the cubic air inlet transition ring 8 and enters the range that increases in the middle of 8 more big and more of cubic air inlet transition ring, and the range that constantly reduces from the middle of 8 to the cubic air inlet transition ring 8 of cubic air inlet transition ring is more and more big, satisfies following requirement:

D”>0,0<＝X<L/2；

D”>0,L/2<＝X<＝L。

d "is the second derivative of D.

Experiments show that the combustion efficiency can be further improved by about 10 percent by the arrangement.

The air inlet hole is a cylindrical flow guide pipe 13, and the flow guide pipe 13 penetrates through the outer wall surface of the cylinder and is communicated with the diffusion combustion air supply channel. Preferably, the flow guide pipe 13 extends 3mm in height from the wall surface and has an inner diameter of 10 mm.

Preferably, a plurality of round holes 15 are uniformly formed in the middle height of the small-diameter column ring of the tertiary air inlet transition ring 8 of the diffusion combustion chamber, and a plurality of through holes 14 are formed in the circumferential direction of the large-diameter transition thin plate and are respectively used for fuel oil combustion at the end of the diffusion combustion without being exhausted and the organization and fuel oil combustion of the internal flow field of the diffusion combustion chamber.

The second end (i.e. the tail part, the air outlet position in fig. 1) of the tertiary air inlet transition ring 8 is connected with a waste gas flue 17, a waste heat utilization heat exchange device is arranged in the waste gas flue, the waste heat utilization heat exchange device comprises a heat exchange core 18, a heat exchange core front support 19 and a heat exchange core rear support 20, the heat exchange core 18, the front support 19 and the rear support 20 are arranged in the waste gas flue 17, the heat exchange core 18 comprises an upper cover plate 21, a lower cover plate 22 and a plurality of heat exchange tubes, the heat exchange tubes are connected and penetrate through the upper cover plate 21 and the lower cover plate 22, the front support 19 and the rear support 20 are respectively positioned at two ends of the heat exchange core 18 and form a gas side channel of the heat exchange device together with the heat; the heat exchange device is characterized in that the front support body 1 is connected with an upper heat exchange core body cover plate 21, a lower cover plate 22 and a flue 17 pipe wall, the rear support body 19 is connected with the upper heat exchange core body cover plate 21, the lower cover plate 22 and the flue 17 pipe wall, and the front support body 19, the rear support body 20, the heat exchange core body cover plate and the flue 17 pipe wall jointly form a liquid inlet header 23 and an outlet header 24 of the heat exchange device.

According to the heat exchange device, the pipe wall is used as one part of the inlet header and the outlet header of the heat exchange device, the inlet header and the outlet header of the heat exchange device are formed by utilizing the pipe wall of the flue, the whole heat exchange device is arranged in the waste gas flue, the independent arrangement of the inlet header and the outlet header is avoided, the heat exchange device occupies less space, the volume and the weight of a heat exchange core body are reduced, and the structure is compact.

Preferably, the front support 19 and the rear support 20 are tubular structures, two ends of the tube wall of the front support 19 are connected with the

lower cover plates

21 and 22 and the flue tube wall, and two ends of the tube wall of the rear support 20 are connected with the

lower cover plates

21 and 22 and the flue tube wall.

By so arranging, the front supporter 19 and the rear supporter 20 respectively form an exhaust gas inlet and an exhaust gas outlet on the exhaust gas side of the heat exchange device, further making the structure compact.

Preferably, the duct walls of the front and

rear supports

19, 20 are connected to the duct wall of the flue 17 by an intermediate member 25, and the intermediate member 25 is of a curved plate-like configuration, as shown in fig. 1.

Preferably, a water inlet pipe (not shown) and a water outlet pipe 27 of the heat exchange device are respectively arranged on the pipe wall of the flue 17 and are respectively communicated with the inlet header and the outlet header.

Preferably, the inlet header is located at a lower portion of the flue and the outlet header is located at an upper portion of the flue.

Preferably, the heat exchange pipe includes a circular pipe 26, and the circular pipe 26 is arranged perpendicular to the flow direction of the exhaust gas, and the diameter of the circular pipe 26 is smaller along the flow direction of the exhaust gas. If the distance from the exhaust gas inlet is S, the inner diameter of the circular tube is D, and if D is F (S), F '(S) <0, and F' (S) is the first derivative of F (S).

Because the inlet waste gas temperature of the waste heat utilization heat exchange device is very high, the liquid in the heat exchange pipe forms a steam-water mixture, and the proportion of a vapor phase in the steam-water mixture is lower and higher and the proportion of a liquid phase is higher and higher along the flowing direction of flue gas. Because the vapor phase proportion of front end is high, the space that consequently occupies is inevitable big, consequently through the change of pipe diameter for the pipe cross-sectional area of heat transfer device's front end is big, thereby makes inner space be enough to satisfy the distribution of liquid phase and satisfy the requirement of heat transfer pipe pressure, avoids anterior heat exchange tube pressure too big, thereby makes whole all heat exchange tube internal pressure of heat transfer core even, avoids having pressure too big, extension heat transfer device's life.

Preferably, F "(S) >0, F" (S) is the second derivative of F (S). That is, the diameter of the circular tube is gradually decreased along the flowing direction of the exhaust gas.

Experiments show that the pressure distribution in the round pipes at different positions can be further met by arranging the upper F (S) >0, and the pressure distribution in the heat exchange pipe is further ensured to be uniform.

Preferably, as shown in fig. 10, the round tubes 26 are arranged in a plurality of rows along the flow direction of the flue gas, the round tubes 26 are in a staggered structure, and the distance between the centers of the adjacent round tubes 26 is 1.1 to 1.3 times of the outer diameter of the round tubes 26. The outer diameter of the round tube 26 is the average value of the outer diameters of two adjacent heat exchange tubes.

Preferably, the diameter of the rear row of tubes 26 is 0.93 to 0.98 times the diameter of the adjacent front row of tubes in the direction of flow of the exhaust gases.

The above proportional relationship is the optimum proportional relationship through a large number of experiments. Through the setting of the pipe diameter and the space size, the pressure distribution can be optimal.

Preferably, the front support 19 forms an inlet channel on the gas side and the rear support 20 forms an outlet channel on the gas side.

Preferably, the heat exchange tube comprises a round tube 26, a plurality of separated heat exchange structures 28 are arranged in the round tube 26 in a segmented manner, each separated heat exchange structure 28 comprises a core body and a shell 29, the core body is arranged in the shell 29, the shell 29 is fixedly connected with the inner wall of the round tube 26, the core body comprises a plurality of grid pieces 30, and grid holes 31 are formed by connecting the grid pieces 30.

Because the temperature of the waste gas is very high, the flow in the round pipe can form a gas-liquid two-phase flow, the grid heat exchange dispersion heat exchange structure is arranged in the round pipe, the liquid phase and the gas phase in the two-phase fluid are separated through the dispersion heat exchange structure, the liquid phase is dispersed into small liquid masses, the gas phase is dispersed into small bubbles, the backflow of the liquid phase is inhibited, the gas phase flows smoothly, the flow stabilizing effect is achieved, and the vibration reduction and noise reduction effects are achieved. Meanwhile, the grid dispersed heat exchange structure is arranged, namely, the inner fins are additionally arranged in the heat exchange tube, so that heat exchange is enhanced, and the heat exchange effect is improved.

The invention disperses the gas-liquid two phases at all cross section positions of all heat exchange tubes, thereby realizing the dispersion of gas-liquid interface and gas phase boundary layer on the whole heat exchange tube section and the contact area of the cooling wall surface and enhancing the disturbance, greatly reducing the noise and the vibration and strengthening the heat transfer.

Preferably, the core of the partitioned heat exchange structure 28 is integrally formed.

Preferably, the core of the heat exchange structure 28 is welded by the grid plates 30.

Preferably, the grid pieces 30 are provided with communication holes. Communication between the grating holes 31 is achieved by the communication holes.

Through setting up the intercommunicating pore, can guarantee to communicate each other between the adjacent grid hole, can the pressure between the even grid hole for the fluid flow direction low pressure of high pressure runner, also can further separate liquid phase and gaseous phase when the fluid flows simultaneously, be favorable to further stabilizing two-phase flow.

Preferably, a plurality of the distributed heat exchange structures 28 are arranged in the circular tube 26 along the flowing direction (i.e. the height direction of fig. 13) of the fluid in the circular tube 26, and the distance between the adjacent distributed heat exchange structures is shorter and shorter from the inlet of the circular tube to the outlet of the circular tube. The distance from the inlet of the round pipe is set to be H, the distance between the adjacent dispersed heat exchange structures is set to be L, and L is equal to F₁(H) I.e. L is a function of the height H as a variable and L' is the first derivative of L, the following requirements are met:

L’<0；

the main reason is that the gas in the circular tube carries liquid in the rising process, the circular tube is continuously heated in the rising process, so that more and more gas in gas-liquid two-phase flow is caused, the heat exchange capacity in the circular tube is relatively weakened along with the increase of the gas phase because more and more gas phases in the gas-liquid two-phase flow, and the vibration and the noise thereof are also continuously increased along with the increase of the gas phase. The distance between adjacent dispersed heat exchange structures needs to be set shorter and shorter.

In addition, the section from the outlet of the round tube to the upper collecting tube is suddenly enlarged in space, the change of the space can cause the gas to rapidly flow out and gather upwards, so the change of the space can cause the gathered vapor phase (vapor mass) to enter the condensing collecting tube from the position of the round tube, the vapor mass leaves the position of the connecting tube and rapidly moves upwards due to the poor liquid density of the vapor (vapor), and the liquid at the original space position of the vapor mass pushed away from the wall surface by the vapor mass also rapidly rebounds and impacts the wall surface to form an impact phenomenon. The more discontinuous the gas (vapor) liquid phase, the larger the gas mass accumulation and the larger the water hammer energy. The impact phenomenon can cause larger noise vibration and mechanical impact, and damage to equipment. Therefore, in order to avoid the phenomenon, the distance between the adjacent dispersed heat exchange structures is set to be shorter and shorter, so that the gas phase and the liquid phase are continuously separated in the fluid conveying process, and the vibration and the noise are reduced to the maximum extent.

Through the experiment discovery, through foretell setting, both can reduce vibrations and noise to the at utmost, can improve the heat transfer effect simultaneously.

It is further preferred that the distance between adjacent discrete heat exchange structures increases progressively from the inlet of the tube 26 to the outlet of the tube 26. I.e. S "is the second derivative of S, the following requirements are met:

L”>0；

experiments show that the vibration and the noise can be further reduced by about 10% and the heat exchange effect can be improved by about 11% by the arrangement.

Preferably, the length of each discrete heat exchange structure 28 remains constant.

Preferably, other parameters of the decentralized heat exchange structures (e.g., length, tube diameter, etc.) are kept constant, except for the distance between adjacent decentralized heat exchange structures 28.

Preferably, a plurality of the distributed heat exchange structures 28 are arranged in the circular tube 26 along the height direction of the circular tube 26, and the length of the distributed heat exchange structures 28 is longer from the inlet of the circular tube 26 to the outlet of the circular tube 26. That is, the length of the dispersed heat exchange structure is C, and C is F₂(X), C' is the first derivative of C, and meets the following requirements:

C’>0；

further preferably, the length of the dispersing heat exchange structure is increased from the inlet of the circular tube to the outlet of the circular tube. I.e., C "is the second derivative of C, the following requirement is satisfied:

C”>0；

for example, the distance between adjacent dispersed heat exchange structures may vary.

Preferably, the distance between adjacent dispersed heat exchange structures is kept constant.

Preferably, other parameters of the decentralized heat exchange structure (such as adjacent spacing, pipe diameter, etc.) are kept constant, in addition to the length of the decentralized heat exchange structure.

Preferably, a plurality of dispersing heat exchange structures are arranged in the circular tube 26 along the height direction of the circular tube 26, and the hydraulic diameters of the grid holes 41 in different dispersing heat exchange structures 28 are smaller from the inlet of the circular tube 26 to the outlet of the circular tube 26. That is, the hydraulic diameter of the grid holes of the dispersed heat exchange structure is Z, and Z is F₃(X), Z' is the first derivative of Z, satisfying the following requirements:

Z’<0；

preferably, the hydraulic diameter of the grid holes of the dispersed heat exchange structure is gradually increased from the inlet of the circular tube to the outlet of the circular tube. Namely, it is

Z' is the second derivative of Z, and meets the following requirements:

Z”>0。

Preferably, the length of the dispersive heat exchange structure and the distance between adjacent dispersive heat exchange structures are kept constant.

Preferably, other parameters of the dispersive heat exchange structure (such as length, distance between adjacent dispersive heat exchange structures, etc.) are kept constant, except for the hydraulic diameter of the grid openings of the dispersive heat exchange structure.

Further preferably, as shown in fig. 13, a groove is formed inside the circular tube 26, and the shell 29 of the heat dispersing and exchanging structure 28 is disposed in the groove.

Preferably, the inner wall of the housing 29 is aligned with the inner wall of the tube 26. Through alignment, the inner wall surface of the circular tube is on the same plane, and the smoothness of the surface is guaranteed.

Preferably, the thickness of the housing 29 is smaller than the depth of the groove, so that the inner wall surface of the circular tube is formed with the groove, thereby performing enhanced heat transfer.

More preferably, as shown in fig. 14, the circular tube 26 is formed by welding in a multi-stage structure, and the dispersed heat exchange structure 28 is provided at the joint of the multi-stage structure. The circular tube with the dispersed heat exchange structure is simple to manufacture and low in cost in the mode.

Through analysis and experiments, the distances among the dispersed heat exchange structures cannot be too large, the vibration and noise reduction effect is poor if the distances are too large, meanwhile, the distances cannot be too small, the resistance is too large if the distances are too small, and similarly, the outer diameters of the grid holes cannot be too large or too small, the vibration and noise reduction effect is poor or the resistance is too large, so that the vibration and noise reduction is optimized under the condition that normal flow resistance (the total pressure bearing is less than 2.5Mpa, or the on-way resistance of a single round pipe is less than or equal to 5Pa/M) is preferentially met through a large number of experiments, and the optimal relation of each parameter is arranged.

Preferably, the distance between the adjacent dispersed heat exchange structures is L, the length of each dispersed heat exchange structure is C, the diameter of each heat exchange tube is D, the fluid circulation area of each grid hole is A, and the circumference of each grid hole is Z, so that the following requirements are met:

L/C＝a-b*LN(D/E)；

E＝4*A/Z；

wherein LN is a logarithmic function, a, b are parameters, wherein 4.9< a <6.1,1.3< b < 2.1;

10<D<18mm；

8<C<15mm；

25<L<35mm。

preferably, 5.4< a <5.8,1.6< b < 1.9;

preferably, a is 5.52 and b is 1.93.

The space S of the dispersed heat exchange structures is the distance between two opposite ends of the adjacent dispersed heat exchange structures; namely the distance between the tail end of the front dispersed heat exchange structure and the front end of the rear dispersed heat exchange structure. See in particular the label of fig. 13.

The diameter D of the heat exchange tube means an average of the inner diameter and the outer diameter.

Preferably, the length S of the round tube is between 140 and 200 mm. More preferably, 160-180 mm.

By optimizing the optimal geometric dimension of the formula, the optimal effect of shock absorption and noise reduction can be achieved under the condition of meeting the normal flow resistance.

Further preferably, a is continuously decreased and b is continuously increased as D/E is increased.

For other parameters, such as the wall thickness of the pipe and the wall thickness of the shell, the parameters are set according to normal standards.

Preferably, the grid apertures 34 extend the entire length of the distributed heat exchange structure 28. I.e., the length of the grid apertures 34 is equal to the length of the dispersive heat exchange structure 28.

Through the arrangement, heat transfer can be further enhanced, and the heat exchange efficiency can be improved.

Preferably, the inner wall of the heat exchange tube is provided with a groove, the shell of the dispersed heat exchange structure is arranged in the groove, and the inner wall of the shell is aligned with the inner wall of the circular tube.

Preferably, the remaining grid openings, except for the grid openings formed by the housing 29, are square.

Preferably, the heat exchange tube comprises a round tube 26 and a flat tube 32, and the round tube 26 is distributed at the front end of the flat tube 32. I.e. along the flow direction of the exhaust gases, the round tubes 26 and the flat tubes 32 are distributed in succession.

The main reason lies in that waste gas inlet side temperature is high, therefore liquid boils easily, thereby form vapour-liquid two-phase flow, because the shape of pipe is circular, even under the same heat transfer area condition, pipe flow area is big, make the bearing capacity reinforce, and along with the heat transfer of flue gas, the flue gas temperature of rear end is lower relatively, consequently, can use flat pipe, flat pipe is long and flat because the shape is prolate, the circulation space is little, liquid can not boil at the rear end, consequently, do not need the big passageway can satisfy the pressure requirement, and flat pipe heat transfer area is big, thereby make the intensive heat transfer. Therefore, the distribution of the flat pipes and the round pipes enables the pressure distribution of the heat exchange device to be relatively uniform on the whole, the phenomenon that the pressure is too large is avoided, and the heat exchange capacity is relatively increased.

Preferably, the fluid flow area of a single round tube is larger than that of a single flat tube.

Preferably, the fluid flow area of a single round tube is 2-3 times the flow area of a single flat tube.

Preferably, the circular tube 26 is placed in front of the heat exchange core, the circular tube 26 has multiple rows, each row includes multiple circular tubes 26, and two adjacent rows of circular tubes 26 are distributed in a staggered manner. Flat pipe 32 divide the multirow next-door neighbour pipe heat transfer structure to arrange in heat transfer core rear side, every row contains a plurality of flat pipe 32, and two adjacent rows of flat pipe preceding, back one-to-one.

The extension direction of the flat tubes 32 is parallel to the flow direction of the flue gas.

Preferably, the flow direction of the liquid in the round tubes 26 and the flat tubes 32 is perpendicular to the flow direction of the exhaust gas.

Preferably, the flat tubes are internally provided with fins 36 to divide the liquid flow channels in the flat tubes into a plurality of small flow channels. Preferably, the hydraulic diameters of the small flow channels in the different flat tubes become smaller along the direction of the flow of the exhaust gas. And if the distance from the waste gas inlet is S, the hydraulic diameter of the flat tube small flow passage is d, and if d is F (S), F '(S) <0, and F' (S) is the first derivative of F (S).

The main reason is along the flow direction of waste gas, and the pressure that needs bear in the flat intraductal pipe is littleer and more, consequently can diminish the water conservancy diameter, diminishes through diminishing the water conservancy radius moreover, can increase heat transfer area, improves heat transfer ability. Therefore, by means of the arrangement of the characteristics, the pressure requirement can be met, and the enhanced heat transfer can be realized.

Preferably, the hydraulic diameter d of the flat tube small flow channel increases continuously along the flow direction of the waste gas. I.e. F "(S) >0, F" (S) being the second derivative of F (S).

For F (S) >0, the heat exchange effect can be obviously improved, and pressure balance is realized. The above results are obtained by a number of numerical simulations and experiments.

Preferably, the small flow channels in the same flat tube have a smaller hydraulic radius along the direction of liquid flow. And if the distance from the waste gas inlet is S, the hydraulic diameter of the flat tube small flow passage is d, and if d is F (S), F '(S) <0, and F' (S) is the first derivative of F (S).

Preferably, the hydraulic diameter d of the same flat tube small flow channel along the flowing direction of the waste gas is increased continuously. Then F "(S) >0, F" (S) is the second derivative of F (S). For the same reasons as before.

Preferably, the small flow channels in the flat tubes are rectangular in cross-section and have dimensions of 2x4 mm.

Preferably, the cross section of the small flow channel between the flat tubes is triangular.

Preferably, the front support and the rear support are of a hollow square-round transition structure, one side end face is square, and one side end face is round, wherein the square end face of the front support is connected with one side end face of the round tube of the heat exchange core body and is fixed and sealed, and the round end face is fixed and sealed with the air outlet at the rear end face of the front combustion chamber mounting cylinder; the square end face of the rear supporting body is connected with one side end face of the flat tube of the heat exchange core body and is fixed and sealed, and the round end face of the rear supporting body is fixed and sealed with the air outlet of the rear flange device.

Preferably, the waste heat utilization heat exchange device is arranged in an exhaust gas flue of the combustor, preferably a flue of the heater.

Preferably, the exhaust gas flue 17 is a combustion chamber installation cylinder.

Preferably, the exhaust gas inlet temperature of the heat exchange device is 1200-1400 degrees Celsius, preferably 1300 degrees Celsius. Preferably, the front row of round tubes is made of high-temperature resistant stainless steel.

Preferably, the heat exchange device is provided with

air outlets

34 and 35, the air outlet 34 is arranged on the pipe wall of the waste gas flue 17 of the upper header, and the air outlet 35 is arranged on the water outlet pipe. Preferably, the

exhaust ports

34, 35 are automatically exhausted according to the pressure condition.

Preferred embodiments will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic block diagram of an embodiment of a premixed ignition, diffusion combustor. In the embodiment, the premixed ignition and diffusion combustor is made of heat-resistant alloy steel materials, and the combustor is formed by sequentially connecting and fixing the air supply installation base, the premixed ignition chamber, the diffusion combustion chamber and the combustion chamber outer cylinder from front to back. The air supply installation base is composed of an installation support 1 and a combustion air supply circular plate 2, the installation support 1 is a step shape gradually closing up, the combustion air supply circular plate 2 is embedded in a circular hole of the lower end face of the installation support 1, and the two lower end faces are coplanar. The center of the combustion air supply circular plate 2 is provided with a circular vent hole, and the circumference is provided with a plurality of fan annular vent holes which are not uniformly distributed. The premixing ignition chamber is composed of a rotational flow generation plate 3, a flow distribution device 4 and a sleeve 5, the flow distribution device 4 is provided with a plurality of ventilation holes in two layers along the axial direction, the upper layer is a premixing air outlet 10, the lower layer is a premixing air inlet 11, the rotational flow generation plate 3 is coaxially arranged between the two layers of ventilation holes of the flow distribution device and close to the premixing air outlet, the flow distribution device 4 provided with the rotational flow generation plate 3 is coaxially fixed in the sleeve 5, the bottom surface is coplanar with the bottom surface of the sleeve 5, the joint is sealed, the upper end surface of the flow distribution device is lower than the upper end surface of the sleeve, and a flow. The front part of the combined premixing ignition chamber penetrates into the central hole of the combustion air supply circular plate 2 to be fixed. The diffusion combustion chamber is composed of a transition cylinder 6, a two-layer air inlet cylinder 7 and a three-layer air inlet transition ring 8, the transition cylinder 6 is in a conical ring shape, a plurality of round holes with the central shafts vertical to the conical surface are circumferentially arranged, the two-layer air inlet cylinder 7 is cylindrical with two ends open, the diameter of the two-layer air inlet cylinder 7 is the same as that of the transition cylinder 6 in large diameter, the front end face of the transition cylinder is aligned and fixed with the rear end face of the transition cylinder 6, a hollow guide pipe 13 which is circumferentially distributed is fixed at the middle height of the two-layer air inlet cylinder 7 and communicated with the outer surface of the cylinder, the three-layer air inlet transition ring 8 is fixed with the lower end face of the two-layer air inlet cylinder 7 through a transition thin plate. The upper end surface of the combined diffusion combustion chamber is coaxially aligned and fixed with the lower end surface of the premixed combustion chamber. The outer cylinder 9 of the combustion chamber is sleeved outside the combined air supply installation base, the premixed combustion chamber and the diffusion combustion chamber, the lower end faces are fixed after being aligned in a coplanar mode, and the fixed positions are kept sealed. A diffusion air inlet channel 17 is formed among the outer cylinder of the combustion chamber, the air supply installation base, the premixed ignition chamber and the diffusion combustion chamber.

Specifically, as shown in fig. 1 and fig. 2, the mounting bracket 1 is a stepped cylinder with gradually changing diameter, the upper end surface is provided with a mounting flange for axial positioning of the burner, and the outer side surface is provided with a mounting and fixing boss for circumferential positioning of the burner. The mounting bracket 1 is used for mounting a warmer control system and an ignition system, guiding airflow to flow towards the inlet of the combustion chamber, increasing the flow speed of the airflow, and is also a carrier for mounting the combustion air supply circular plate 2 and the combustion chamber outer cylinder 8. In this embodiment, the inside diameter of the mounting bracket is in turn: 186mm, 163mm, 138mm, and a mounting flange diameter of 198 mm.

Specifically, the combustion air supply circular plate 2 is used for distributing air required by combustion, air flowing through the circular vent hole enters the premixing combustion chamber to participate in combustion in the ignition stage and the diffusion combustion stage of the premixing ignition chamber, air flowing through the fan-shaped circumferential vent hole enters the diffusion combustion chamber to participate in combustion in the diffusion combustion stage, and preferably, the area ratio of the circular vent hole to the fan-shaped circumferential vent hole is 3.7: 1. In this embodiment, the circular ventilation holes of the circular combustion air supply circular plate 2 shown in fig. 2 are provided with guide grooves at the periphery thereof, so as to facilitate the installation and fixation of the premixed ignition chamber, and 8 sector ring holes with the same radial dimension are non-uniformly distributed, preferably, the central angles and the spacing central angles of 7 adjacent sector rings are the same, respectively 19 ° and 26 °, and the central angle of the other sector ring is 23.5 °, and the spacing angle between the other sector ring and the adjacent sector ring is 17 ° and 30.5 °.

Specifically, the premixing ignition chamber shunting device 4 is axially provided with two layers of ventilation holes corresponding to the front and the back, the number of each layer of ventilation holes is 6, the upper premixing air outlet 10 is used for shunting air entering from the circular ventilation holes of the combustion air supply circular plate 2, the shunted air enters the lower premixing air inlet 11 through the shunting channel 16, is mixed with atomized fuel oil and retards the fuel oil to descend, the mixing time of the fuel oil and the air is prolonged, and the diffusion combustion stability is improved. Be provided with the whirl between the two-layer ventilation hole and take place board 3, the whirl takes place the preferred interval in the plane that board front end face and upper premix air outlet centre of a circle place is 6mm with the upper strata, the center is equipped with the round hole, as atomizing fuel entry, circumference is equipped with the cross-section and takes place the whirl passageway that the board plane is certain angle for triangle-shaped and its normal direction and whirl for form the whirl in the ignition chamber, see fig. 3, preferentially, whirl passageway cross-section triangle-shaped corresponds the interior angle and is 6 °, 65 °, the board contained angle is taken place with the whirl to the cross. A part of air entering from the circular vent hole of the combustion air supply circular plate 2 enters the rear combustion space through the rotational flow channel on the rotational flow generating plate 3 and is fully mixed with atomized fuel entering through the central circular hole to form combustible mixed gas required by ignition.

Specifically, the diffusion combustion chamber transition cylinder 6 is in a conical ring shape, and preferably, the diameter ratio of the front end surface to the rear end surface is 9: 13, the number of the circumferential round holes is 16, the diameter is 8mm, and the circumferential round holes are uniformly distributed. The two-layer air inlet cylinder 7 is cylindrical with openings at two ends, the diameter of the two-layer air inlet cylinder is equal to the diameter of the rear end face of the transition cylinder, preferably, the 1/2-height position of the cylinder in the axial direction is provided with guide pipes distributed along the circumference, the number of the guide pipes is 10, and the guide pipes are communicated with and aligned with the outer end face of the cylinder. Referring to fig. 4, the three-layer air intake transition ring 8 is provided with return holes 14 and three-layer air intake holes 15 for connecting the diffusion air intake channel with the interior of the diffusion combustion chamber, preferably, the number of the return holes 14 and the three-layer air intake holes 15 is 8 and 36 respectively, and the diameter is 10mm and 2mm respectively. The required air of burning gets into diffusion inlet air channel 17 by 2 circumference fan ring holes of fuel air feed plectane to respectively get into the inside participation burning of diffusion combustion chamber by 6 circumference round holes of transition section of thick bamboo, honeycomb duct 13 on the secondary air inlet drum 7, backward flow hole 14 and three-layer air inlet 15 on the three-layer air inlet transition ring 8, preferred, each layer air inlet area of diffusion combustion chamber accounts for the proportion of diffusion combustion air inlet area and is: 44%, 15%, 35% and 6%. The circumferential round hole of the transition cylinder 6 is a main air supply channel for diffusion combustion, so that the entering air enters the flame along the normal direction of the conical surface, the air content of the unburned fuel oil in the flame is increased, and the combustion efficiency is improved. The high-speed air entering from the flow guide pipe 13 on the secondary air inlet cylinder 7 forms an air barrier in the middle of the combustion chamber, and the air barrier is mixed with atomized fuel oil to be combusted, so that the axial moving speed of flame is reduced, the residence time of the fuel oil in the combustion chamber is prolonged, the full mixing and combustion are ensured, and the measure is favorable for reducing the axial length required by the fuel oil combustion. Air entering the combustion chamber through the backflow hole 14 in a backflushing mode separates atomized fuel oil from the inner wall of the combustion chamber, reduces the attachment probability of the fuel oil on the wall surface, is beneficial to eliminating carbon deposition, meanwhile, the air adheres to the conical surface of the transition cylinder in the ascending process to change the flowing direction, interacts with the air entering the transition cylinder 6 in the circumferential direction, forms tumble flow on the upper portion of the secondary air inlet cylinder 7, and promotes mixing and combustion of the air and the unburned fuel oil. The air entering from the tertiary air inlet holes 15 delays the flame movement speed at the tail end of the combustion chamber, ensures the combustion of a small amount of unburnt fuel oil, improves the combustion efficiency of the combustor, reduces the length of the combustion tail flame and reduces the heat load of the rear heat exchanger.

The assembled burner works initially, the fuel spray nozzle integrated on the boiler head assembly of the heater sprays atomized fuel, the fuel enters the rear space of the rotational flow generating plate through the central circular hole on the rotational flow generating plate, meanwhile, air entering the rear space through the rotational flow channels circumferentially arranged on the rotational flow generating plate is fully mixed with the atomized fuel to form oil-gas mixed gas required by ignition, and the mixed gas is ignited by the ignition device integrated on the boiler head assembly to form a flame core required by the continuous work of the burner. After ignition is successful, the ignition device stops working, the fuel injection nozzle continues to inject fuel, the fuel is mixed with air entering from the rotational flow channel and the premixed air inlet and then forms a stable fire source in the space behind the rotational flow generation plate in the premixed ignition chamber, and the fuel which is not burnt out in the premixed ignition chamber continues to move towards the inside of the diffusion combustion chamber. Meanwhile, air required by diffusion combustion enters the flow dividing channel through the fan-shaped holes in the circumferential direction of the combustion air supply circular plate, enters the diffusion combustion chamber through the air inlet holes of the transition cylinder, the secondary air inlet cylinder, the tertiary air inlet transition ring and the like, and is continuously contacted with the unburned fuel surface and combusted in the process, and generated waste gas is discharged out of the combustor through the small-diameter hole of the outer cylinder of the combustion chamber.

The premixed ignition and diffusion combustor is suitable for small fuel oil type combustion heat exchange devices such as a warmer and the like, has the characteristics of simple structure and high combustion efficiency, the premixed ignition chamber structure can ensure reliable ignition and stable combustion of the combustor under various extreme environments, and the multilayer air intake diffusion combustion structure is beneficial to reducing the axial length of a combustion chamber and improving the volume power of the combustor.

Although the present invention has been described with reference to the preferred embodiments, it is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A burner system comprises a burner outer barrel, an air supply installation base, a pre-mixing ignition chamber and a diffusion combustion chamber, wherein the air supply installation base, the pre-mixing ignition chamber and the diffusion burner are sequentially connected in series, the air supply installation base comprises an installation support and a combustion air supply circular plate, the first end of the installation support is open, the second end of the installation support is provided with the combustion air supply circular plate, the combustion air supply circular plate comprises a central ventilation hole and a circumferential ventilation hole, and the circumferential ventilation hole is of a fan-shaped structure taking the center of the central ventilation hole as the circle center; circumference ventilation hole has set up 8, 8 circumference ventilation holes are asymmetric distribution, and specifically the distribution is: the area of the circumferential vent hole at the lowest part is larger than that of the circumferential vent holes at other positions; the diffusion combustion chamber comprises a transition cylinder, a secondary air inlet cylinder and a tertiary air inlet transition ring, wherein the rear end of the transition cylinder is connected with one end of the secondary air inlet cylinder, the other end of the secondary air inlet cylinder is connected with the first end of the tertiary air inlet transition ring, the transition cylinder is provided with air inlet holes, the secondary air inlet cylinder is provided with air inlet holes, and the tertiary air inlet transition ring is provided with an air inlet; one end of the tertiary air inlet transition ring is a large-diameter end;

the transition cylinder of the diffusion combustion chamber is in a conical ring shape, and a plurality of round holes are uniformly distributed in the circumferential direction of the transition cylinder and are used as a main gas supply channel of diffusion combustion;

one end of the transition cylinder is a large-diameter end, two ends of the secondary air inlet cylinder of the diffusion combustion chamber are in open design, one end of the secondary air inlet cylinder is connected with the large-diameter end of the transition cylinder to form a diffusion combustion space, and the other end of the secondary air inlet cylinder is connected with the large-diameter end of the tertiary air inlet transition ring to be used as a diffusion combustion exhaust channel.

2. The burner system of claim 1, wherein the total area ratio of the central vent to the circumferential vent is (3.5-4.5): 1.

3. The burner system of claim 2 wherein the center angles of 7 other ring sectors are the same and the spacing angles of 7 other adjacent ring sectors are the same.