CN211600690U

CN211600690U - Low-resistance full-premix gas burner structure with self-adaptive load and stable combustion

Info

Publication number: CN211600690U
Application number: CN201922390476.1U
Authority: CN
Inventors: 赵钦新; 王宁; 商俊奇; 邵怀爽; 梁志远; 王云刚
Original assignee: Xian Jiaotong University
Current assignee: Xian Jiaotong University
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-09-29
Anticipated expiration: 2029-12-27

Abstract

The utility model relates to a load self-adaptation surely fires low resistance full premix gas burner structure, including air-blower, premixing chamber, burner, ignition electrode and detection device. The gas can be respectively arranged at the inlet and the outlet of the blower so as to form a front premixing mode and a rear premixing mode. The burner head is composed of an inner layer and an outer layer of coaxial cylinders and is fixed at the outlet end of the premixing chamber through a flange, the outer cylinder wall is provided with or not provided with a gap nozzle with the same shape and size as the cross section of the nozzle of the inner cylinder, the inner cylinder can carry out load self-adaptive axial movement along with the change of air supply quantity and air supply pressure along a straight guide rail arranged on the inner wall of the outer cylinder, and the available area of the gap nozzle on the inner cylinder wall and the outer cylinder wall and the mixed air ejection speed are automatically adjusted. The utility model discloses the available nozzle area of well burner cylinder wall changes the emergence self-adaptation along with the load size that gas volume and air feed pressure arouse and changes, and the burner resistance is low, effectively prevents that the high load from taking off fire and low-load tempering, realizes full load stable combustion, safe and reliable, and application scope is wide.

Description

Low-resistance full-premix gas burner structure with self-adaptive load and stable combustion

Technical Field

The utility model belongs to natural gas safety and stability burning, combustor design field of heat energy engineering, concretely relates to load self-adaptation surely fires low resistance full premix gas burner structure.

Background

The full-premixing gas combustion mode has the obvious advantages of high combustion strength, short flame, small combustion equipment volume, low CO and NOx content in combustion products and the like, but the problems of tempering at low load and fire release at high load are difficult to avoid, and the development of the full-premixing gas combustor in civil use and industry is greatly limited.

The prior full-premix burner comprises a full-premix surface gas burner and a premix water-cooling gas burner, wherein the premix water-cooling gas burner is mainly applied to a large-capacity gas boiler; the surface burners with the small holes densely distributed on the metal cylindrical barrel and the ceramic plate are widely used for gas boilers with medium and small capacities, the 3 full premixing surface gas burners have better anti-backfire capability due to the measures of multilayer metal fiber sintering, multilayer metal fiber weaving, small hole dense distribution and the like, but almost all have the fatal defect of large resistance, and the small holes are easily blocked after particles in the air are gathered, so that the resistance is greatly increased, the output of the burners and the boilers is reduced, and the burners are required to be cleaned frequently. For this reason, we begin to think of reducing the resistance by opening a rectangular slit along the surface of the cylindrical metal cylinder, and obtaining better effect. However, when the burner product is dimensioned for a nominal load with a rectangular gap, the risk of low-load flashback can occur; if the dimensions of the rectangular slot are designed for low loads, the risk of misfiring may occur during nominal load operation. In order to prevent backfire and misfire, some patents also provide an anti-backfire ring and an anti-backfire ring or a flow guider and the like in the combustion head at the same time, and the modes have complex structures, so that the mixed gas can not be combusted at the optimal flow speed under the condition of variable load, and the problem of combustion stability still exists. The fully premixed gas burner with the load self-adaption low-resistance stable combustion well solves the problem.

Disclosure of Invention

An object of the utility model is to overcome above-mentioned prior art's shortcoming, provide a load self-adaptation surely fires low resistance full premix gas burner structure, adaptation becomes the needs of load on a large scale when reducing gas mixture outlet resistance, can both run safely and stably under full load, do not temper and do not take off a fire. The utility model discloses only explain with the burning in full premix as the example, the scheme is applicable to the burning in partial premix formula equally.

In order to achieve the above purpose, the utility model adopts the following technical scheme to realize:

a load self-adaptive stable combustion low-resistance full-premix gas burner structure comprises a blower, a premix chamber, a burner head, an ignition electrode and a detection device;

the blower, the premixing chamber and the combustion head are connected in sequence through flanges;

the air blower is provided with an air inlet, and the fuel gas inlet is arranged at the air inlet of the air blower or at the premixing chamber so as to form front premixing and rear premixing;

the ignition electrode and the detection device are both arranged on a flange connecting the premixing chamber and the combustion head and extend to one end of the combustion head, and the detection device is used for detecting flame and temperature conditions;

the combustion head comprises an outer barrel and an inner barrel, wherein the wall surface of the inner barrel is provided with a nozzle, the wall surface of the outer barrel is provided with or not provided with a nozzle, the nozzles are uniformly or non-uniformly and tightly distributed, and a certain margin is reserved at the two ends of the outer barrel and the inner barrel and not provided with a nozzle;

one end of the outer cylinder is connected with the outlet end of the premixing chamber through a flange, and the other end of the outer cylinder is arranged in the hearth;

the inner cylinder is arranged on the guide rail on the inner wall surface of the outer cylinder, and can perform self-adaptive axial movement along the guide rail along with the increase or decrease of the flow speed of the mixed gas to increase or decrease the available area of the nozzle, so that the phenomenon of fire escape or backfire caused by too large or too small flow speed of the mixed gas is prevented, and the safe and stable operation of the combustor under full load is maintained.

The outer barrel and the inner barrel of the combustion head are formed by rolling high-temperature-resistant anti-oxidation dry-burning sheet materials, the two ends of the outer barrel are open, one end of the inner barrel close to the premixing chamber is open, the other end of the inner barrel is plugged by a bottom plate, the outer barrel and the inner barrel are identical in height and coaxial, the wall surfaces of the inner barrel and the outer barrel are tightly matched, and only a gap meeting the requirement of thermal expansion is reserved.

The outer cylinder is fixed at the outlet end of the premixing chamber through a flange, 3-6 guide rails are laid between the inner cylinder and the outer cylinder along the inner wall of the outer cylinder along the axial direction of the inner cylinder and the outer cylinder, the length of one end, close to the premixing chamber, of each guide rail is longer than the height of the inner cylinder and the height of the outer cylinder by the original length of a spring, the guide rails are connected with one end, close to the premixing chamber, of the inner cylinder through the springs, and the inner cylinder can perform self-adaptive axial movement; the left end of the inner cylinder and the left end of the outer cylinder are coincident to form an initial position without introducing mixed gas, and the spring is in an original length state at the moment.

When the wall surface of the outer cylinder is not provided with the nozzle, the wall surface of the inner cylinder is provided with the transverse gap nozzle which is vertical to the axial direction, and the short edge of the nozzle is parallel to the axial direction of the inner cylinder and the outer cylinder.

The guide rail is provided with a clamping groove, the inner cylinder cannot be separated from the guide rail, the clamping groove is positioned at 1/4 the height of the inner cylinder and the outer cylinder from one end of the inner cylinder close to the premixing chamber to one end of the outer cylinder far away from the premixing chamber, the spring is still in an elastic limit at the moment and a certain margin is reserved, and the nozzle on the wall surface of the inner cylinder is only arranged on the wall surface of 3/4 one end of the inner cylinder far away from the premixing chamber.

When the outer cylinder and the inner cylinder are provided with transverse gap nozzles with the same shape and size, the nozzles are arranged on the whole wall surface, and the short edges of the nozzles are axially parallel to the inner cylinder and the outer cylinder; the spouts on urceolus and the inner tube one-to-one, and the corresponding minor face that corresponds the spout is located same straight line all the time.

And the outer barrel nozzle is arranged closer to one nozzle short edge at one end far away from the premixing chamber than the inner barrel nozzle.

The spring stiffness coefficient of the spring is larger than that of the spring stiffness coefficient of the outer barrel wall surface non-nozzle scheme.

The ignition electrode adopts a high-voltage ignition electrode.

Compared with the prior art, the utility model discloses following beneficial effect has:

1. the resistance of the outlet of the burner is small, and the output of the burner and the boiler is improved.

2. The back fire and the fire of the full-premix gas burner are prevented, and the running safety of the combustion equipment is ensured.

3. The method is suitable for the requirement of large-range load adjustment, and can maintain the stable operation of the combustor under the full load and ensure the stability of the operation.

4. Frequent cleaning of the combustion head and frequent switching of the combustor are avoided, the service life of the equipment is prolonged, the operating cost is reduced, and the operating continuity is ensured.

5. The burner is suitable for the requirements of different gas combustion, and the burner is not required to be redesigned when the gas is replaced.

Drawings

Fig. 1 is a structural diagram of the burner of the present invention.

Fig. 2a is a schematic view of a burner head according to a first embodiment of the present invention.

Fig. 2b is a model diagram of a combustion head according to the first embodiment of the present invention.

Fig. 3a is a schematic view of a burner head according to a second embodiment of the present invention.

Fig. 3b is a model diagram of a combustion head according to a second embodiment of the present invention.

Wherein: 1-a blower, 2-an air inlet, 31-a fuel gas inlet, 4-a premixing chamber, 51, a first fixed flange, 52, a second fixed flange, 6-a combustion head, 61-an outer cylinder, 611-an outer cylinder transverse gap nozzle, 62-an inner cylinder, 621-an inner cylinder transverse gap nozzle, 63-a guide rail, 64-a spring and 65-a clamping groove.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings:

referring to fig. 1, a low resistance fully premixed gas burner structure with self-adaptive load and stable combustion comprises a blower 1, a premixing chamber 4, a burner 6, an ignition electrode 7 and a detection device 8. The blower 1, the premix chamber 4 and the burner head 6 are connected in series by a first fixing flange 51 and a second fixing flange 52. The blower 1 is provided with an air inlet 2 and a gas inlet 31, and the gas inlet 31 is arranged at the blower 1 or the premixing chamber 4 to form a front premixing and a rear premixing respectively. The ignition electrode 7 and the detection device 8 are both arranged on the second fixing flange 52 and extend to one side of the combustion head 6, the ignition electrode 7 adopts a high-voltage ignition electrode, and the detection device 8 is used for detecting flame and temperature conditions;

the gas is introduced from the gas inlet 31, the air is introduced from the air inlet 2, the blower 1 rotates to cause the gas and the air to generate strong disturbance, the gas and the air are uniformly mixed in the enough space of the premixing chamber 4 and then enter the combustion head 6, and are sprayed out from a nozzle on the combustion head 6 and are combusted in the hearth after being ignited by the ignition electrode 7.

Referring to FIG. 2a or FIG. 3a, the combustion head is composed of an inner cylinder and an outer cylinder, both formed by rolling a high temperature resistant, oxidation resistant and dry-burning thin plate material, the inner cylinder and the outer cylinder are the same in height and coaxial, the diameter of the inner cylinder 62 is slightly smaller than that of the outer cylinder 61, the outer cylinder 61 is fixed at the outlet end of the premixing chamber through a flange, the wall surfaces of the inner cylinder and the outer cylinder are tightly matched, only a gap meeting the requirement of thermal expansion is reserved, 3-6 straight guide rails 63 are laid along the inner wall of the outer cylinder 61 along the axial direction of the inner cylinder and the outer cylinder between the inner cylinder and the outer cylinder, the length, the guide rail 63 is connected with the inner cylinder 62 through the spring 64, the inner cylinder 62 can perform load self-adaptive axial movement along the guide rail 63 along with the change of the air supply quantity and the air supply pressure, when one end of the inner cylinder and the outer cylinder close to the premixing chamber 4 is coincident, the initial position is the initial position without the mixed air, and at the moment, the spring is in the original length state. The outer cylinder 61 is open at two ends, the inner cylinder 62 is open at one end close to the premixing chamber 4, and the other end is blocked by a bottom plate. The inner cylinder 62 is provided with inner cylinder transverse slit nozzles 621 perpendicular to the axial direction of the cylinder on the wall surface, the outer cylinder 61 is provided with or not provided with outer cylinder transverse slit nozzles 611 which are identical in shape and size with the inner cylinder nozzles and are in one-to-one correspondence with the inner cylinder nozzles on the wall surface, and certain allowance is left at the positions of the inner cylinder and the outer cylinder close to the two ends without the nozzles.

Two different embodiments are as follows:

the first preferred scheme is as follows:

referring to fig. 2a and 2b, the burner head of the low-resistance fully premixed gas burner with self-adaptive load and stable combustion comprises an outer cylinder 61, an inner cylinder 62, an inner cylinder transverse slit nozzle 621, a guide rail 63, a spring 64 and a clamping groove 65.

The end of the combustion head inner and outer cylinders close to the premixing chamber 4 is used as the left end, and the other end is used as the right end.

The wall surface of the outer cylinder 61 is not provided with a nozzle, the wall surface of the inner cylinder 62 is provided with an inner cylinder transverse slit nozzle 621 vertical to the axial direction of the cylinder, and the short side of the inner cylinder transverse slit nozzle 621 is parallel to the axial direction of the inner cylinder and the outer cylinder. The guide rail 63 is provided with a clamping groove 65, the inner cylinder 62 can not be separated from the guide rail 63, the limit position of the right movement of the inner cylinder 62 is 1/4 that the left end of the inner cylinder 62 is separated from the right end of the outer cylinder 61 by about the height of the inner cylinder and the outer cylinder, the inner cylinder transverse slit nozzle 621 is only arranged on the wall surface of the right end 3/4 of the inner cylinder 62, and the spring 64 is still in the elastic limit and has a certain margin when in the limit position.

The even mixture of gas and air enters the inner space of the inner cylinder 62 from the left end and then is sprayed out through the inner cylinder transverse slit nozzle 621, and due to the shielding effect of the wall surface of the outer cylinder 61 on the inner cylinder transverse slit nozzle 621, the available nozzle area can be changed by moving the inner cylinder 62, and the outlet gas flow rate can be changed.

After the mixture of gas and air enters the inner cylinder 62, the inner cylinder 62 is pushed to move rightwards along the guide rail 63, the flow rate of the mixture is larger, the wind pressure is higher, the rightwards movement distance of the inner cylinder 62 is larger, the area of the blocked inner cylinder transverse slit nozzle 621 is smaller, and the outlet of the mixture is larger; when the load is reduced, the flow rate of the mixed gas is reduced, the air pressure is reduced, the spring 64 drives the inner cylinder 62 to move leftwards, the area of the blocked inner cylinder transverse slit nozzle 621 is increased, and the mixed gas outlet is reduced. The flow speed of the mixed gas outlet is increased or reduced along with the change of the outlet, so that the fire is prevented from being extinguished or tempered due to too large or too small flow speed of the mixed gas, and the safe and stable operation of the combustor under the full load is maintained.

The preferred scheme II is as follows:

referring to fig. 3a and 3b, the burner head of the low-resistance fully premixed gas burner with self-adaptive load and stable combustion comprises an outer cylinder 61, an outer cylinder transverse slit nozzle 611, an inner cylinder 62, an inner cylinder transverse slit nozzle 621, a straight guide rail 63, a spring 64 and a clamping groove 65.

Hereinafter, the end of the combustion head inner and outer tube near the premixing chamber 4 is also used as the left end, and the other end is used as the right end.

The outer cylinder 61 and the inner cylinder 62 are respectively provided with an outer cylinder transverse slit nozzle 611 and an inner cylinder transverse slit nozzle 621 which are perpendicular to the axial direction on the wall surface, and the short sides of the outer cylinder transverse slit nozzle 611 and the inner cylinder transverse slit nozzle 621 are parallel to the axial direction of the inner cylinder and the outer cylinder. The shape and size of the inner and outer tube spouts are completely the same and are in one-to-one correspondence, the corresponding short sides of the corresponding spouts are always positioned on the same straight line, the outer tube transverse gap spout 611 and the inner tube transverse gap spout 621 are uniformly or non-uniformly and tightly arranged on the whole wall surfaces of the outer tube 61 and the inner tube 62, certain allowance is left at the two ends of the outer tube 61 and the inner tube 62 to avoid the spouts, and the outer tube transverse gap spout 611 is arranged at a distance close to the right short side of the spout than the inner tube transverse gap spout 621. A clamping groove 65 is formed in the position, on the guide rail 63, of one short nozzle side away from the left end of the outer cylinder 61, and the inner cylinder 62 can only move for the distance of one short nozzle side along the guide rail 63. The left end of each guide rail 63 is fixed with a spring 64 connected with the inner cylinder 62, the spring has the same original length as the spring in the first proposal but has a larger stiffness coefficient than the spring in the first proposal, and the spring 64 is within the elastic limit range and has a certain margin when the inner cylinder 62 moves to the extreme position in the right direction.

The even mixture of gas air gets into inner tube 62 inner space from premixing room exit end and then spouts through the superimposed spout of interior outer tube, inner tube transverse gap spout 621 is sheltered from completely at the beginning, when inner tube 62 moved the distance of a spout minor face along the guide rail right, interior outer tube transverse gap spout coincidence, inner tube transverse gap spout 621 was not sheltered from this moment, available nozzle area reaches the biggest, because the outer tube 61 wall to the sheltering effect of inner tube transverse gap spout 621, it can change the size of available nozzle area to remove inner tube 62, change the export gas velocity of flow.

After the mixture of gas and air enters the inner cylinder 62, the inner cylinder 62 is pushed to move along the guide rail 63, the larger the flow rate of the mixture is, the higher the wind pressure is, the larger the rightward movement distance of the inner cylinder 62 is, the smaller the shielded area of the inner cylinder transverse slit nozzle 621 is, and the larger the mixed gas outlet is; when the load is reduced, the flow rate of the mixed gas is reduced, the air pressure is reduced, the spring 64 drives the inner cylinder 62 to move leftwards, the shielded area of the inner cylinder transverse slit nozzle 621 is increased, and the mixed gas outlet is reduced. The flow speed of the mixed gas outlet is increased or reduced along with the change of the outlet, so that the fire is prevented from being extinguished or tempered due to too large or too small flow speed of the mixed gas, and the safe and stable operation of the combustor under the full load is maintained.

Claims

1. A load self-adaptive stable-combustion low-resistance full-premix gas burner structure is characterized in that the burner comprises a blower, a premix chamber, a burner head, an ignition electrode and a detection device;

2. The low-resistance full-premix gas burner structure with self-adaptive and stable combustion of load according to claim 1, characterized in that the outer cylinder and the inner cylinder of the burner are made of high-temperature-resistant and oxidation-resistant sheet materials by rolling, the two ends of the outer cylinder are open, one end of the inner cylinder close to the premixing chamber is open, the other end is blocked by a bottom plate, the outer cylinder and the inner cylinder are same in height and coaxial, the wall surfaces of the inner cylinder and the outer cylinder are tightly matched, and only a gap meeting the requirement of thermal expansion is reserved.

3. The structure of the low-resistance fully premixed gas burner with self-adaptive stable combustion under load of claim 1, wherein the outer cylinder is fixed at the outlet end of the premixing chamber by a flange, 3-6 guide rails are axially laid along the inner wall of the outer cylinder between the inner cylinder and the outer cylinder along the inner wall of the outer cylinder, the length of one end of each guide rail close to the premixing chamber is longer than the height of the inner cylinder by the original length of a spring, the guide rails are connected with one end of the inner cylinder close to the premixing chamber through springs, and the inner cylinder can perform self-adaptive axial movement along the guide rails along with the change of air supply amount and air supply pressure;

the left end of the inner cylinder and the left end of the outer cylinder are coincident to form an initial position without introducing mixed gas, and the spring is in an original length state at the moment.

4. The low-resistance fully premixed gas burner structure with self-adaptive load and stable combustion of claim 1, wherein when the outer cylinder wall has no nozzle, the inner cylinder wall is provided with a transverse gap nozzle perpendicular to the axial direction, and the short side of the nozzle is parallel to the axial direction of the inner and outer cylinders.

5. The structure of claim 4, wherein the guide rail is provided with a notch, the inner barrel cannot be separated from the guide rail, the notch is located at 1/4 the height of the inner barrel from the end of the inner barrel close to the premixing chamber to the end of the outer barrel away from the premixing chamber to the end of the inner barrel away from the premixing chamber, the spring is still in the elastic limit and has a certain margin, and the nozzle on the wall surface of the inner barrel is only arranged on the wall surface of 3/4 the inner barrel away from the premixing chamber.

6. The structure of the low-resistance fully premixed gas burner with self-adaptive load and stable combustion according to claim 1, wherein when the outer cylinder and the inner cylinder are provided with transverse slit nozzles with the same shape and size, the nozzles are arranged on the whole wall surface, and the short sides of the nozzles are axially parallel to the inner cylinder and the outer cylinder;

the spouts on urceolus and the inner tube one-to-one, and the corresponding minor face that corresponds the spout is located same straight line all the time.

7. The structure of claim 6, wherein the outer barrel nozzle is arranged closer to one nozzle short side far away from the premixing chamber than the inner barrel nozzle.

8. The structure of claim 7, wherein the guide rail is provided with a slot, the slot is one short side of the nozzle at the end of the slot close to the premixing chamber from the outer cylinder, the slot is at the extreme position of the inner cylinder moving towards the end far away from the premixing chamber, the original length of the spring is the same as that of the outer cylinder wall surface non-nozzle scheme, but the stiffness coefficient of the spring is greater than that of the outer cylinder wall surface non-nozzle scheme.

9. The structure of the low-resistance fully premixed gas burner with self-adaptive load and stable combustion of claim 1, wherein the ignition electrode is a high-voltage ignition electrode.