CN113357634B

CN113357634B - Plane flame combustion device and combustion system

Info

Publication number: CN113357634B
Application number: CN202110718448.7A
Authority: CN
Inventors: 刘训臣; 齐飞; 周继斌
Original assignee: Shanghai Jiaotong University
Current assignee: Shanghai Jiaotong University
Priority date: 2021-06-28
Filing date: 2021-06-28
Publication date: 2022-11-25
Anticipated expiration: 2041-06-28
Also published as: CN113357634A

Abstract

The application relates to the technical field of heat energy and discloses a planar flame combustion device and a combustion system. In the present application, a planar flame combustion apparatus includes a housing formed with an output surface; a plurality of fuel gas pipelines, a plurality of oxidizing gas pipelines and a plurality of protective gas pipelines which are sealed with each other and extend in the shell; one end of each of the fuel gas pipelines, the oxidizing gas pipelines and the protective gas pipelines is communicated to the respective airflow sources; the other ends of the plurality of fuel gas pipelines and the plurality of oxidizing gas pipelines are open ends and are positioned on the output surface to form a combustion area of the plane flame; the other ends of the plurality of shielding gas pipes are open ends and are positioned on the output surface to form a shielding gas area. The utility model provides a plane flame burner can not produce the tempering phenomenon after the burning area mixes the back ignition burning, and makes flame blow off stably, produces the even plane flame of temperature, and has avoided blowing off the heat-conduction and the heat radiation loss of flame, and the flame temperature can reach adiabatic flame temperature.

Description

Plane flame combustion device and combustion system

Technical Field

The application relates to the technical field of heat energy, in particular to a plane flame combustion device and a combustion system.

Background

Laser combustion diagnostic techniques are widely used in modern combustion research, some requiring a standard flame as a calibration source. The quality of the standard flame can influence the error of the laser combustion technology measurement to a great extent, so that the standard flame has the characteristics of laminar flow, stability, heat insulation, convenience in analog calculation of temperature and species concentration and the like. The flat flame is a standard flame, and the most common flat flame burner is a McKenna flame furnace, in which the central area of the plate is a flame stabilizing area, which can generate a stable flat flame. Many important reaction kinetic model data as well as spectral measurement data have been obtained with the McKenna flame furnace. The inventors have found that McKenna flame furnaces also have the following disadvantages: because of the adoption of premixed flame, the danger of backfire can be generated, meanwhile, the flame is stabilized at an outlet, and the temperature is reduced due to conduction heat transfer, but because of the heat dissipation problem of the McKenna flame furnace, the flame temperature is not close to the adiabatic flame temperature due to the addition of cooling water in the furnace body, and the change range of the equivalence ratio is not large due to the premixing of fuel, so that the standard flame has a plurality of limitations. The deviation of the flame temperature generated by the McKenna flame furnace from the adiabatic flame temperature was measured in some experiments using nitrogen spectroscopy using a continuous anti-stokes raman scattering method.

Disclosure of Invention

An object of this application is to provide a plane flame burner and combustion system for can not produce the tempering phenomenon after the burning of firing after the combustion area mixes, and flame blows off stably, produces the even plane flame of temperature, and has avoided blowing off the heat conduction and the heat radiation loss of flame, and the flame temperature can reach adiabatic flame temperature.

In order to solve the above technical problem, a first aspect of the present application provides a planar flame combustion apparatus, comprising: a housing formed with an output surface; a plurality of fuel gas pipelines, a plurality of oxidizing gas pipelines and a plurality of protective gas pipelines which extend in the shell and are sealed with each other; one end of each of the plurality of fuel gas pipelines, the plurality of oxidizing gas pipelines and the plurality of protective gas pipelines is communicated to respective airflow sources; the other ends of the plurality of fuel gas pipelines and the plurality of oxidizing gas pipelines are open ends and are positioned on the output surface to form a combustion area of the plane flame; the other ends of the plurality of shielding gas pipes are open ends and are positioned on the output surface to form a shielding gas area.

A second aspect of the present application provides a flat flame combustion system comprising: the above-described flat flame combustion device; the control system is used for controlling the flow of the fuel gas, the oxidizing gas and the protective gas; and the ignition device is used for igniting the mixed gas of the fuel gas and the oxidizing gas.

This application embodiment is for prior art, plane flame burner makes combustion gas and air can not produce the backfire phenomenon after the mixed ignition burning of casing surface through the breather pipe of mutual sealing in this application, and flame blows off stably, produce the even plane flame of temperature, prevent heat transfer for burner because of flame blows off, even if dry combustion method also can not burn out the device, cooling system's cost has been saved, and the heat conduction and the heat radiation loss of blowing off flame have been avoided, flame temperature can reach adiabatic flame temperature.

In an embodiment of the first aspect, further comprising within the housing: the fuel gas chamber, the oxidizing gas chamber and the protective gas chamber are sealed with each other; one end of each of the plurality of shielding gas pipelines is communicated to a gas flow source of the fuel gas through the fuel gas chamber; one end of each of the plurality of protective gas pipelines is communicated to an airflow source of the oxidizing gas through the oxidizing gas chamber; one end of each of the plurality of shielding gas pipelines is communicated to a gas flow source of shielding gas through the shielding gas chamber.

In an embodiment of the first aspect, the arrangement between the plurality of fuel gas conduits and the plurality of oxidizing gas conduits presents a composite structure having a plurality of cell structures between the respective open ends in the combustion zone; wherein each unit structure comprises: a structure in which open ends of a first number of oxidant gas conduits are arranged around open ends of a second number of fuel gas conduits, wherein the first number is at least 1 and the second number is at least 2.

In an embodiment of the first aspect, the open ends of the respective oxic gas conduits in each cell structure are arranged in a regular hexagon; the combined structure is honeycomb-shaped.

In an embodiment of the first aspect, the oxidation gas pipes corresponding to each unit structure are arranged in a circumferential direction of the corresponding at least one fuel gas pipe.

In an embodiment of the first aspect, the cross-section of each fuel gas conduit is circular and the cross-section of each oxidizing gas conduit is regular hexagonal.

In an embodiment of the first aspect, the shielding gas zone is arranged around the combustion zone.

In an embodiment of the first aspect, the combustion zone and the shield gas zone are separated by a cooling slot.

In an embodiment of the first aspect, the combustion zone is square.

In an embodiment of the first aspect, the housing comprises a fuel gas port, an oxidation gas port, and a shielding gas port, and the three sources of external gas flow receive a fuel gas, an oxidizing gas, and a shielding gas, respectively, through the fuel gas port, the oxidation gas port, and the shielding gas port, and/or wherein the fuel gas is methane, the oxidizing gas is air, and the shielding gas is nitrogen.

Drawings

FIG. 1 is a schematic view of a flat flame combustion device according to a first embodiment of the present invention;

FIG. 2 is a schematic view of the output surface of a flat flame combustion device according to a first embodiment of the present application;

fig. 3 is a schematic structural diagram of a unit structure of an output surface in the first embodiment of the present application.

Detailed Description

The following description of the embodiments of the present application is provided by way of specific examples, and other advantages and effects of the present application will be readily apparent to those skilled in the art from the disclosure herein. The present application is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present application. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

Embodiments of the present application will be described in detail below with reference to the accompanying drawings so that those skilled in the art to which the present application pertains can easily carry out the present application. The present application may be embodied in many different forms and is not limited to the embodiments described herein.

In order to clearly explain the present application, components that are not related to the description are omitted, and the same reference numerals are given to the same or similar components throughout the specification.

Throughout the specification, when a device is referred to as being "connected" to another device, this includes not only the case of being "directly connected" but also the case of being "indirectly connected" with another element interposed therebetween. In addition, when a device "includes" a certain constituent element, unless otherwise specified, it means that the other constituent element is not excluded, but may be included.

When a device is said to be "on" another device, this may be directly on the other device, but may be accompanied by other devices in between. When a device is said to be "directly on" another device, there are no other devices in between.

Although the terms first, second, etc. may be used herein to describe various elements in some instances, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, the first interface and the second interface, etc. are described. Also, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes" and/or "including," when used in this specification, specify the presence of stated features, steps, operations, elements, components, items, species, and/or groups, but do not preclude the presence, or addition of one or more other features, steps, operations, elements, components, species, and/or groups thereof. The terms "or" and/or "as used herein are to be construed as inclusive or meaning any one or any combination. Thus, "A, B or C" or "A, B and/or C" means "any of the following: a; b; c; a and B; a and C; b and C; A. b and C ". An exception to this definition will occur only when a combination of elements, functions, steps or operations are inherently mutually exclusive in some way.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the singular forms "a", "an" and "the" include plural forms as long as the words do not expressly indicate a contrary meaning. The terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

Terms representing relative spatial terms such as "lower", "upper", and the like may be used to more readily describe one element's relationship to another element as illustrated in the figures. This term is intended to include not only the meaning indicated in the drawings, but also other meanings or operations of the device in use. For example, if the device in the figures is turned over, elements described as "below" other elements would then be oriented "above" the other elements. Thus, the exemplary terms "under" and "beneath" all include above and below. The device may be rotated 90 or other angles and the terminology representing relative space is also to be interpreted accordingly.

Although not defined differently, including technical and scientific terms used herein, all terms have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Terms defined in commonly used dictionaries are to be additionally interpreted as having meanings consistent with those of related art documents and the contents of the present prompts, and must not be excessively interpreted as having ideal or very formulaic meanings unless defined.

Referring to the drawings, a first embodiment of the present application will be described, and as shown in fig. 1, the present flat flame combustion apparatus includes a housing 1, a fuel gas chamber 2, an oxidizing gas chamber 3 and a shielding gas chamber 4 are included in the housing 1, the three chambers are sealed with each other, the fuel gas chamber 2, the oxidizing gas chamber 3 and the shielding gas chamber 4 respectively have a fuel gas port 20, an oxidizing gas port 30 and a shielding gas port 40, the fuel gas port 20, the oxidizing gas port 30 and the shielding gas port 40 respectively communicate with three external gas flow sources, which are fuel gas, oxidizing gas and shielding gas respectively. In some embodiments, the fuel gas is methane, the oxidizing gas is air, and the shielding gas is nitrogen, but it is understood that the fuel gas may be other combustible gases, the oxidizing gas may be oxygen, and the shielding gas may be other inert gases that are not readily combustible. The fuel gas, the oxidizing gas and the protective gas can be provided by a high-pressure gas cylinder, and the flow rates of the three gases are respectively controlled by a flowmeter and a computer in a remote way. For example, valves may be controlled at the fuel port, the oxidant port and the guard port, and the valve size may be controlled remotely.

The housing 1 is formed with an output surface 5 which may be disposed, for example, but not limited to, at a top position of the housing 1. As shown in fig. 2, the output surface 5 comprises two regions, namely a flame combustion region 51 in the middle and a shielding gas region 52 surrounding the combustion region 51. As shown in fig. 2 and 3, a plurality of fuel gas pipes 21, a plurality of oxidizing gas pipes 31, and a plurality of shielding gas pipes 41 extending inside are provided in the housing 1. Wherein one end of the plurality of fuel gas ducts 21 communicates with the fuel gas chamber 2, one end of the plurality of oxidizing gas ducts 31 communicates with the oxidizing gas chamber 3, and the other ends of the plurality of fuel gas ducts 21 and the plurality of oxidizing gas ducts 31 are open ends and are located at the output surface 5 of the housing 1 to form a combustion zone 51 for a flat flame. One end of the plurality of shielding gas ducts 41 communicates with the shielding gas chamber 4 and the other end is also open and is located at the output surface 5 of the housing 1 to form a shielding gas region 52 for a planar flame. It should be noted that the plurality of fuel gas lines 21, the plurality of oxidizing gas lines 31, and the plurality of shielding gas lines 41 may, in some embodiments, be connected directly to the respective gas flow sources. In some embodiments, to increase Tunable Diode Laser Absorption Spectroscopy (TDLAS) measured Absorption optical length, the burn zone 51 side length may be designed to be 2 inches. In the middle combustion zone 51, the arrangement between the fuel gas conduit 21 and the oxidizing gas conduit 31 is further present between the respective open ends as a combined structure having a plurality of unit structures. Specifically, each unit structure includes: the open ends of the first number of oxidant gas pipes 31 are arranged around the open ends of the second number of fuel gas pipes 21. Wherein the first number is at least 1 and the second number is at least 2. In some embodiments, as shown in FIG. 3, each fuel gas conduit 21 and six oxidizing gas conduits 31 comprise a single cell structure. The six oxidation gas pipelines 31 are arranged in a regular hexagon, and the combined structure of the open ends is in a honeycomb shape. A plurality of fuel gas pipes are arranged in the casing 1 in a row, the outer diameter of the pipes is 0.8mm, the inner diameter of the pipes is 0.5mm, and the side length of the oxidation gas pipe 31 is 0.5 mm. The fuel gas pipe 21 is communicated with the fuel gas chamber 2 at the bottom from the output surface 5 of the shell 1 and is isolated from the oxidizing gas pipe 31, the fuel gas enters the fuel gas chamber 2 from the fuel gas port 20 and reaches the output surface 5 through the fuel gas pipe 21, the air enters the oxidizing gas chamber 3 from the oxidizing gas port 30 and reaches the output surface 5 through the oxidizing gas pipe 31, the fuel gas and the oxidizing gas are isolated from each other in the shell 1, and when reaching the output surface 5, diffusion flame is formed and further combined to form non-premixed planar flame. The plane flame combustion area is less and the combustion reaction is rapid, air and fuel react soon and the mixing is even after breaking away from open end, flame is in stable laminar flow flame state, the flame temperature is even, the highest temperature can reach 2500K, prevent heat transfer for burner because of the flame blows off, even if dry combustion can not burn out the device, saved cooling system's cost, and avoided the heat-conduction and the heat radiation loss of blowing off flame, the flame temperature can reach adiabatic flame temperature.

The shielding gas enters the shielding gas chamber 4 from the shielding gas port 40, flows out of the shielding gas area 52 to form shielding gas flow after passing through the shielding gas pipeline 41 to the output surface 5, so that the influence of the surrounding gas flow on the plane flame when the combustion device works is prevented, and the error of experimental measurement is reduced. In addition, the oxidizing gas conduits 31 corresponding to each unit structure are arranged along the circumferential direction of the corresponding fuel gas conduit 21, each oxidizing gas conduit 31 may extend vertically along the fuel gas conduit 21 to the oxidizing gas chamber 3, or as shown in fig. 1, the fuel gas conduit 21 inside the housing 1 is surrounded by a large conduit 6, the oxidizing gas conduit 31 only extends vertically in the top region and partially enters the large conduit 6, the large conduit 6 is communicated with the oxidizing gas chamber 3 and also communicated with the oxidizing gas conduit 31 at the top, and the air entering the oxidizing gas chamber 3 rises into the plurality of oxidizing gas conduits 31 at the top through the gaps between the fuel gas conduits 21 after entering the large conduit 6, so that the material cost of the oxidizing gas conduits 31 can be saved by adopting such a surrounding structure. As shown in fig. 3, the cross section of the fuel gas pipe 21 is circular, and the cross section of the oxidizing gas pipe 31 is regular hexagon, but it is understood that the fuel gas pipe 21 may be regular hexagon, that is, the fuel gas pipe 21 and the oxidizing gas pipe 31 are both regular hexagons with the same length of cross section and the combined structure is honeycomb. Similarly, the cross section of the shielding gas pipe 41 may be circular or regular hexagonal.

The circular stove plate structure has certain disadvantage when using optical measurement technique, when the circumstances such as the skew of emergence laser or incident position deviation, because circular inherent geometric feature will lead to measuring the difference that optical path difference and shooting image appear to arouse measuring error, consequently the combustion area is set as the square in this application, and the corresponding protective gas region that surrounds can all be square inside and outside, also can be inboard square, outside circular. By the arrangement, optical path difference and difference of shot images caused by the circular features can be reduced, and measurement errors can be reduced.

In some embodiments, the combustion zone 51 and the shield gas zone 52 are separated by a cooling slot 53. The cooling channel 53 is located between the combustion zone 51 and the shield gas zone 52 and may serve the dual function of a cooling duct and a barrier.

The planar flame combustion device of this application embodiment for can not produce the tempering phenomenon after the burning area mixes the back ignition burning, and make flame be in stable laminar flame state through controlling the gaseous speed in advance, produce the even planar flame of temperature, prevent heat transfer for burner because of the flame blows off, even if dry combustion also can not burn out the device, cooling system's cost has been saved, and the heat conduction and the heat radiation loss of blowing off the flame have been avoided, the flame temperature can reach adiabatic flame temperature.

A second embodiment of the present application protects a flame combustion system comprising the above-described planar flame combustion apparatus; the control system is used for controlling the flow of fuel gas, oxidizing gas and protective gas to ensure that combustion flame reaches a stable laminar flame state; and the ignition device is used for igniting the mixed gas of the fuel gas and the oxidizing gas. An object of the application is to provide a plane flame burner for can not produce the tempering phenomenon after the burning area mixes the postignition burning, and make flame be in stable laminar flow flame state through controlling the gaseous speed in advance, produce the even plane flame of temperature, prevent heat transfer for burner because of flame blows off, even if dry combustion method also can not burn out the device, cooling system's cost has been saved, and the heat conduction and the heat radiation loss of blowing off flame have been avoided, flame temperature can reach adiabatic flame temperature.

The above embodiments are merely illustrative of the principles and utilities of the present application and are not intended to limit the application. Any person skilled in the art can modify or change the above-described embodiments without departing from the spirit and scope of the present application. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical concepts disclosed in the present application shall be covered by the claims of the present application.

Claims

1. A flat flame combustion device, comprising:

a housing formed with an output surface;

a plurality of fuel gas pipelines, a plurality of oxidizing gas pipelines and a plurality of protective gas pipelines which extend in the shell and are sealed with each other;

one end of each of the plurality of fuel gas pipelines, the plurality of oxidizing gas pipelines and the plurality of shielding gas pipelines is communicated to respective airflow sources;

the other ends of the plurality of fuel gas pipelines and the plurality of oxidizing gas pipelines are open ends and are positioned on the output surface to form a combustion area of the plane flame; the other ends of the plurality of shielding gas pipelines are open ends and are positioned on the output surface to form a shielding gas area;

wherein the arrangement between the plurality of fuel gas conduits and the plurality of oxidizing gas conduits presents a honeycomb composite structure having a plurality of cell structures between each open end in the combustion zone; wherein each unit structure comprises: a structure in which the open ends of 6 oxidizing gas conduits are arranged around the open ends of 1 fuel gas conduit; wherein the outer diameter of the fuel gas pipeline is 0.8mm, the inner diameter is 0.5mm, and the section of the oxidizing gas pipeline is a regular hexagon with the side length of 0.5 mm.

2. The flat flame combustion device of claim 1, further comprising, within the housing: the fuel gas chamber, the oxidizing gas chamber and the protective gas chamber are sealed with each other;

one end of each of the plurality of shielding gas pipelines is communicated to a gas flow source of the fuel gas through the fuel gas chamber; one end of each of the plurality of protective gas pipelines is communicated to an airflow source of the oxidizing gas through the oxidizing gas chamber; one end of each of the plurality of shielding gas pipelines is communicated to a gas flow source of shielding gas through the shielding gas chamber.

3. The flat flame combustion device of claim 1, wherein the shielding gas zone is disposed around the combustion zone.

4. The flat flame combustion device of claim 3, wherein the combustion zone and the shield gas zone are separated by a cooling slot.

5. The flat flame combustion device of claim 1, wherein the combustion zone is square.

6. The flat flame combustion device of claim 1, wherein the housing includes a fuel gas port, an oxidation gas port, and a shielding gas port, and the gas flow source receives a fuel gas, an oxidant gas, and a shielding gas through the fuel gas port, the oxidation gas port, and the shielding gas port, respectively, and/or wherein the fuel gas is methane, the oxidant gas is air, and the shielding gas is nitrogen.

7. A flame combustion system, comprising:

the flat flame combustion device of claims 1-6;

the control system is used for controlling the flow of the fuel gas, the oxidizing gas and the protective gas;

and the ignition device is used for igniting the mixed gas of the fuel gas and the oxidizing gas.