CN107543203B - Two-stage composite swirl nozzle for gaseous fuel low-pollution combustion chamber - Google Patents
Two-stage composite swirl nozzle for gaseous fuel low-pollution combustion chamber Download PDFInfo
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- CN107543203B CN107543203B CN201710717236.0A CN201710717236A CN107543203B CN 107543203 B CN107543203 B CN 107543203B CN 201710717236 A CN201710717236 A CN 201710717236A CN 107543203 B CN107543203 B CN 107543203B
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Abstract
The invention relates to a two-stage composite swirl nozzle for a gaseous fuel low-pollution combustion chamber, which comprises an advanced swirler 1, a main combustion stage swirler 2, a simplified flame tube 3, a diffuser 4, a stationary flame 5, a main vortex 6 and an adherent jet 7. The on-duty swirler 1 and the main combustion stage swirler 2 interact to form a stationary flame 5, and then a knockout flame is formed; the mixing and ignition effects of the on-duty high-equivalence-ratio combustion product and the main combustion fresh gas are enhanced, the temperature, the flame length and the residence time of a main combustion zone are reduced, the aim of low emission is fulfilled, the stable working range is widened, the selection of fuel types is increased, and the problems of tempering, carbon deposition and the like do not occur any more. The low-temperature adherent jet 7 provides a natural thermal barrier, so that the wall surface of the simplified flame tube 3 is kept at a lower temperature, complex cooling structure designs such as a floating wall and the like are basically avoided, the weight of the simplified flame tube 3 is reduced, the design complexity is reduced, the strength of the simplified flame tube 3 is increased, and the protection effect is better.
Description
Technical Field
The invention belongs to the field of application of a gas turbine graded low-pollution combustion chamber, and particularly relates to a two-stage composite swirl nozzle for a gaseous fuel low-pollution combustion chamber.
Background
In order to realize the low emission requirement, the method must start from the aspects of reducing the temperature of the main combustion area, shortening the retention time of fuel gas in the high-temperature area, improving the uniformity and the like. Although lean premixed combustion can achieve the purpose of low emissions, completely homogeneous lean premixed combustion has disadvantages of unstable combustion and the like in terms of a low-pollution combustion mechanism, and thus when a lean premixed combustion technique is applied, a staged or stratified combustion method is often employed. Foreign researchers research the working mode of the duty class, and find that when the duty class adopts premixed flame for stable combustion, the NOx emission can be effectively reduced compared with the duty class adopting diffusion flame, and meanwhile, the stability is good. Nevertheless, because the duty-level equivalent is high, the problems of tempering, carbon deposition and the like are still easily generated, and meanwhile, local high temperature still exists, and the residence time of fuel gas in a high-temperature area is long, which is not beneficial to emission control. The tempering problem is particularly serious when the hydrogen-doped fuel is used; when the synthetic gas and the pyrolysis gas are used as fuel, the gas component change range is large, so that the flame propagation speed fluctuation range is large, and the flame pulsation is severe. This is a disadvantage for low emission technology applications.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide the two-stage composite swirl nozzle for the gaseous fuel low-pollution combustion chamber, which can be combusted in the full working condition range (comprising gaseous fuels such as hydrogen-containing fuel, pyrolysis gas, synthesis gas, natural gas and the like), can obviously reduce local high temperature, reduce the retention time of fuel gas in a high-temperature area, obviously reduce pollutant emission, has simple and compact structure and good working effect.
The purpose of the invention is realized as follows:
the invention relates to a two-stage composite swirl nozzle for a gaseous fuel low-pollution combustion chamber, which comprises an on-duty swirler 1, a diffuser 4, a main combustion stage swirler 2 and a simplified flame tube 3, and is characterized in that the on-duty swirler 1 consists of a hollow cylindrical hub 12 and curved blades 11, the main combustion stage swirler 2 consists of triangular blades 21, a base plate 22 and a top plate 23, the diffuser 4 consists of a flat section and an expansion section, the main combustion stage swirler 2 and the diffuser 4 are integrated, high equivalence ratio mixed gas enters from the on-duty swirler 1, the ratio of on-duty flow W 1 to main combustion stage flow W 2 is W 1: W 2: 1:6, the center of the hollow cylindrical hub 12 is also filled with air, the central straight-through air flow is used for inhibiting the back pressure gradient at the downstream of the outlet of the on-duty swirler 1 to generate adherent jet flow 7, the adherent jet flow 7 interacts with the main vortex 6 to form a stationary flame 5, and further form stable detached flame, and low equivalence mixed gas enters from the main combustion stage swirler 2 to form the main combustion stage vortex flow 6 and the adherent jet flow 7.
The installation angle of the curved blade 11 is between 25 and 45 degrees, and the length of the hollow cylindrical hub 12 is slightly larger than the chord length of the curved blade 11; the number-class equivalence ratio is between 0.6 and 1, and the global equivalence ratio is between 0.2 and 0.3.
The diameter of the outlet of the expansion section is slightly smaller than the inner diameter of the outlet of the main combustion stage cyclone 2 to form a step 24 with the height of 2-5 mm, a small vortex is generated at the step, and two stages of wall-attached jet flows 7 are separated by a certain distance.
The mounting angle of the triangular blade 21 is between 30 and 45 degrees; the main combustion stage swirler 2 adopts a strong swirl number design, and the swirl number is 0.8-1.26.
Compared with the prior art, the invention has the beneficial effects that:
The grading design of the composite rotational flow enables the duty-level swirler 1 and the main combustion-level swirler 2 to interact to form stable stationary flame 5, and further form stable stripping flame; the mixing and ignition effects of the on-duty high equivalence ratio combustion products and the main combustion grade fresh gas are enhanced, the temperature of a main combustion zone is reduced, and the flame length is reduced. This design also significantly reduces residence time since the high temperature zone is not located at the vortex core. Therefore, the purposes of low emission are achieved, the stable working range is widened, the selection of fuel types is increased, and problems such as tempering, carbon deposition and the like do not occur. In addition, because the low-temperature adherent jet flow 7 flowing through most of the inner surface of the simplified flame tube 3 provides a natural heat barrier layer, the wall surface of the simplified flame tube 3 is kept at a lower temperature, complex cooling structure designs such as cooling holes and floating walls are basically avoided, the weight of the simplified flame tube 3 is reduced, the design complexity is reduced, the strength of the simplified flame tube 3 is increased, the pneumatic design of the simplified flame tube 3 is simplified, and the protection effect is better.
Drawings
FIG. 1 is a schematic structural diagram of the present invention.
fig. 2 is a schematic structural diagram of the duty grade swirler 1 of the present invention.
Fig. 3 is a schematic view of the diffuser 4 according to the present invention.
Fig. 4 is a schematic structural diagram of the main combustion stage swirler 2 of the present invention.
FIG. 5 shows the flow field and streamline distribution of the present invention and the simplified combustor basket 3 assembly.
FIG. 6 is a temperature field distribution during the assembly of the present invention with the simplified liner 3.
FIG. 7 is a graph of velocity and static temperature distribution on the axis of the present invention.
FIG. 8 is a plot of the mass fractions of methane and carbon dioxide on the central axis of the present invention.
Detailed Description
The invention is described in more detail below with reference to the accompanying drawings:
As shown in fig. 1-4, a two-stage composite swirl nozzle for a gaseous fuel low-pollution combustor comprises an overtime swirler 1, a main combustion stage swirler 2, a simplified flame tube 3, a diffuser 4, a stationary flame 5, a main vortex 6 and an adherent jet 7.
The on-duty swirler 1 is composed of a hollow cylindrical hub 12 and curved blades 11, mixed gas with a high equivalence ratio enters from the on-duty swirler 1, the ratio of on-duty flow W 1 to main combustion flow W 2 is W 1: W 2 is 1:6, air also enters from the center of the hollow cylindrical hub 12, reverse pressure gradient at the downstream of the outlet of the on-duty swirler 1 is restrained by utilizing central through air flow, and meanwhile, the jet flow which is rotary expansion, does not generate vortex breaking phenomenon, has a certain speed and does not restrain the main vortex 6 is interacted with the main vortex 6 to form stable stationary flame 5, so that stable detached flame is formed (so that fuel such as pyrolysis gas, synthesis gas and natural gas can be combusted in a whole working condition range), the mixing and ignition effect of on-duty high-equivalence ratio combustion products and main combustion fresh fuel can be enhanced, the temperature of a main combustion zone is reduced, the chord length of the stationary flame 5 is reduced, the chord length of the stationary flame is slightly larger than that of the flame is combusted in a large component range, the chord length of the high-equivalence ratio combustion products is increased, the swirl separation of the hollow combustion products, the swirl blades is reduced, and the flow of the high-duty swirler, the swirl blades is reduced, and the flow diversion of the vanes is reduced, and the flow loss is reduced, and the flow.
The diffuser 4 consists of a straight section and an expansion section. The radial hierarchical structure determines that the relatively cold low equivalence ratio jet flow of the main combustion stage can produce quenching effect on the flame on duty, the quenching effect can greatly increase the CO emission, the combustion efficiency is reduced, and the lean blowout performance in the slow-speed vehicle state is also unfavorable. The diameter of the outlet of the expansion section is slightly smaller than the inner diameter of the outlet of the main combustion stage swirler 2, so that a step 24 with moderate height is formed, the two stages of adherent jet flows 7 are separated by a certain distance, the mixing of the main combustion stage adherent jet flows 7 and the on-duty flame can be delayed, and the time is provided for the full combustion of the on-duty flame. The diffuser 4 and the duty-class swirler 1 act together to control the equivalence ratio distribution area to form diffusion distribution and limit the upward excessive development of the flame of the duty class.
The main combustion stage swirler 2 is composed of triangular blades 21, a bottom plate 22, a top plate 23 and steps 24. The main combustion stage swirler 2 adopts a strong swirl number design and is integrated with the diffuser 4. The low equivalence ratio mixed gas enters from the main combustion stage swirler 2. The rotating flow of appropriate intensity forms a huge main vortex 6 and a high-speed coherent jet 7 that does not touch the simplified flame tube 3 outlet. Since the high-temperature region is not located at the main vortex 6, the main vortex 6 does not increase the residence time and contributes greatly to stabilizing the combustion. The coherent jet 7 is a low temperature, unburned jet, since the potential flow zone velocity of the coherent jet 7 is very high and the on-duty flame is again located in the center of the simplified flame tube 3. When the nozzle structure of the invention is applied, the low-temperature wall-attached jet flow 7 flowing through most of the inner surface of the simplified flame tube 3 provides a natural heat barrier layer, so that the wall surface of the simplified flame tube 3 is kept at a lower temperature, the complex cooling structure designs such as the cooling hole and the floating wall of the simplified flame tube 3 are basically avoided, the weight of the simplified flame tube 3 is reduced, the design complexity is reduced, the strength of the simplified flame tube 3 is increased, the pneumatic design of the simplified flame tube 3 is simplified, and the protective effect is better.
Fig. 5-6 are schematic views of the working state of the present invention. As shown in fig. 5, after the mixed gas with high equivalence ratio of the on-duty swirler 1 flows out of the diffuser 4, a stationary flame 5 is formed near the outlet of the diffuser 4 due to the adverse pressure gradient interaction caused by the rotation expansion of the straight-through gas flow and the main flow, and a suspended heart-shaped backflow region, i.e., a main vortex 6, having a symmetrical double-vortex structure is generated at the central position of the simplified flame tube 3. Due to the forcing action of the class-B cyclone 1, the mixed gas with high equivalence ratio rotates and expands at the outlet and is mixed with the mixed gas at the outlet of the main mixer. As shown in FIG. 6, the on-duty high equivalence ratio mixed gas is fully combusted at the intersection of the low-speed region and the recirculation region, i.e., the stationary flame 5, to form a narrow high-temperature region with a temperature of about 2100K. The temperature at the vortex center of the reflux area is lower and is about 1900K. The outlet airflow of the main combustion stage cyclone 2 generates adherent jet 7 due to the action of strong swirling flow.
In fig. 7, the left ordinate is axial velocity (m/s), the right ordinate is temperature (on), the square broken line is axial velocity, and the circular broken line is temperature; in fig. 8, the left ordinate represents the mass fraction of methane (kg/kg gas), the right ordinate represents the mass fraction of carbon dioxide (kg/kg gas), the square broken line represents the mass fraction of methane, and the circular broken line represents the mass fraction of carbon dioxide. As shown in fig. 7 and 8, a low velocity region of less than 4.248m/s is produced at the exit of the diffuser 4. In the low-speed area, the premixed gas is subjected to chemical reaction rapidly, the temperature is increased rapidly, the change is close to linearity, the slope is nearly vertical to the abscissa axis, the change amplitude is severe, and the length of the stationary flame 5 is greatly shortened. Correspondingly, the mass fraction of methane in the premixed gas is rapidly reduced, the slope of the slope and the slope of the temperature curve are approximately symmetrical about a straight line passing through a crossing point and parallel to an abscissa axis, the temperature is at the tail part of a low-speed area with zero axial speed, the methane and the air are completely reacted, the residual mass fraction is 0, only a main flow in a reflux area is subjected to chemical reaction, but the combustion temperature is not high due to the relatively low equivalence ratio. The high-temperature flame generated on duty is far away from the vortex center, no vortex flow exists, and the dwell time of the fuel gas in the high-temperature area is short.
it will be appreciated by those of ordinary skill in the art that the embodiments described herein are intended to assist the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited embodiments and examples. All such possible equivalents and modifications are deemed to fall within the scope of the invention as defined in the claims.
Claims (4)
1. A two-stage composite swirl nozzle for a gaseous fuel low-pollution combustion chamber comprises an on-duty swirler (1), a diffuser (4), a main combustion stage swirler (2) and a simplified flame tube (3), and is characterized in that the on-duty swirler (1) consists of a hollow cylindrical hub (12) and curved blades (11), the main combustion stage swirler (2) consists of triangular blades (21), a base plate (22) and a top plate (23), the diffuser (4) consists of a straight section and an expansion section, the main combustion stage swirler (2) and the diffuser (4) are integrated, mixed gas with a high equivalence ratio enters from the on-duty swirler (1), the ratio of on-duty flow W 1 to main combustion stage flow W 2 is W 1: W 2: 1:6, mixed gas also enters the center of the hollow cylindrical hub (12), the reverse pressure gradient at the downstream of an outlet of the on-duty swirler (1) is inhibited by the airflow of the center, adherent vortex (7) is generated, the adherent vortex (7) interacts with the main combustion stage swirler (6) to form a fixed equivalent vortex, and the flame is stabilized and the main combustion stage swirler (7) and forms adherent vortex (6) and the adherent vortex and the main combustion stage swirler (2) and the main combustion stage swirler (7) is directly connected with the adherent vortex to.
2. The two-stage compound swozzle for a low contamination combustion chamber of gaseous fuel of claim 1, wherein: the installation angle of the curved blade (11) is between 25 and 45 degrees, and the length of the hollow cylindrical hub (12) is slightly larger than the chord length of the curved blade (11); the number-class equivalence ratio is between 0.6 and 1, and the global equivalence ratio is between 0.2 and 0.3.
3. The two-stage compound swozzle for a low contamination combustion chamber of gaseous fuel of claim 1, wherein: the diameter of the outlet of the expansion section is slightly smaller than the inner diameter of the outlet of the main combustion stage cyclone (2) to form a step (24) with the height of 2-5 mm, a small vortex is generated at the step, and two stages of wall-attached jet flows (7) are separated by a certain distance.
4. The two-stage compound swozzle for a low contamination combustion chamber of gaseous fuel of claim 1, wherein: the mounting angle of the triangular blade (21) is between 30 and 45 degrees; the main combustion stage swirler (2) adopts a strong swirl number design, and the swirl number is 0.8-1.26.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201710717236.0A CN107543203B (en) | 2017-08-21 | 2017-08-21 | Two-stage composite swirl nozzle for gaseous fuel low-pollution combustion chamber |
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| CN201710717236.0A CN107543203B (en) | 2017-08-21 | 2017-08-21 | Two-stage composite swirl nozzle for gaseous fuel low-pollution combustion chamber |
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| CN107543203A CN107543203A (en) | 2018-01-05 |
| CN107543203B true CN107543203B (en) | 2019-12-10 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111006244B (en) * | 2019-12-03 | 2021-02-19 | 哈尔滨工程大学 | Flue gas backflow combustion chamber with variable rotational flow |
| CN115899769B (en) * | 2022-10-17 | 2024-10-11 | 南京航空航天大学 | Combustion chamber with inner-stage concave cavity and outer-stage cyclone coupling |
| CN115751305B (en) * | 2022-10-28 | 2023-05-26 | 北京工商大学 | Low-nitrogen burner |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1909030A2 (en) * | 2006-09-29 | 2008-04-09 | General Electric Company | Methods and apparatus to facilitate decreasing combustor acoustics |
| CN102022753A (en) * | 2010-12-31 | 2011-04-20 | 北京航空航天大学 | Low-pollution combustion chamber with premixed and pre-evaporated precombustion part |
| CN202303463U (en) * | 2011-10-13 | 2012-07-04 | 中国科学院工程热物理研究所 | Fuel oil and air mixing device for low-pollution combustion chamber |
| CN104180397A (en) * | 2014-07-25 | 2014-12-03 | 北京华清燃气轮机与煤气化联合循环工程技术有限公司 | Pre-mixing on-duty nozzle |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070074518A1 (en) * | 2005-09-30 | 2007-04-05 | Solar Turbines Incorporated | Turbine engine having acoustically tuned fuel nozzle |
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- 2017-08-21 CN CN201710717236.0A patent/CN107543203B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1909030A2 (en) * | 2006-09-29 | 2008-04-09 | General Electric Company | Methods and apparatus to facilitate decreasing combustor acoustics |
| CN102022753A (en) * | 2010-12-31 | 2011-04-20 | 北京航空航天大学 | Low-pollution combustion chamber with premixed and pre-evaporated precombustion part |
| CN202303463U (en) * | 2011-10-13 | 2012-07-04 | 中国科学院工程热物理研究所 | Fuel oil and air mixing device for low-pollution combustion chamber |
| CN104180397A (en) * | 2014-07-25 | 2014-12-03 | 北京华清燃气轮机与煤气化联合循环工程技术有限公司 | Pre-mixing on-duty nozzle |
Non-Patent Citations (1)
| Title |
|---|
| 分级预混燃烧的稳定性;张昊等;《动力工程》;20060430;第26卷(第2期);第221-228页 * |
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