CN213513985U - Inside and outside cavity combination configuration standing vortex combustor - Google Patents
Inside and outside cavity combination configuration standing vortex combustor Download PDFInfo
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- CN213513985U CN213513985U CN202022557404.4U CN202022557404U CN213513985U CN 213513985 U CN213513985 U CN 213513985U CN 202022557404 U CN202022557404 U CN 202022557404U CN 213513985 U CN213513985 U CN 213513985U
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Abstract
The utility model provides an inside and outside cavity combination configuration standing vortex combustor. The trapped vortex combustor comprises a diffuser, a combustor shell, an oil delivery pipe, an igniter and a flame tube with a concave cavity combined structure, wherein the combustor shell is connected with the diffuser; defeated oil pipe includes main oil pipe, annular oil pipe and thin oil pipe, defeated oil pipe is the tubular structure, main oil pipe is the metal pipe that can buckle, defeated oil pipe set up quantity be 2 to 6 to the circumference equipartition is installed annular oil pipe is last. The utility model discloses an inside and outside cavity combination configuration resides in the vortex combustion chamber and has increased the outer cavity of combustion chamber, not only helps increasing combustion reaction region and area, more is favorable to the regulation and control of hierarchical subregion burning, does benefit to and improves combustion efficiency and pollutant emission.
Description
Technical Field
The utility model relates to an aeroengine and gas turbine combustor technical field especially relate to an inside and outside cavity combination configuration standing vortex combustor.
Background
The development of modern aircraft engines and gas turbines puts higher requirements on the performance of combustors, and one of the key problems is that the combustors have wider flame stability regions and lower pollutant emission performance. Therefore, various high-efficiency and low-pollution combustion technologies such as a lean oil premixing and pre-evaporation technology, a lean oil direct injection technology, a double-ring premixing and rotational flow combustion technology, a rich combustion-quenching-lean oil technology, a trapped vortex combustion technology and the like are successively proposed and developed in various countries in the world. The standing vortex combustion chamber is a novel combustion chamber which is provided in the last 90 th century, is different from the traditional vortex flame stabilizing combustion chamber, is used for standing vortex flame stabilization by arranging a cavity structure in a combustion chamber channel, and has the characteristics of simple structure, light weight, small total pressure loss and the like. Meanwhile, the standing vortex structure in the concave cavity can avoid the direct influence of the main flow, so that a partitioned and graded combustion mode is formed. In addition, according to the actual working state, the oil-gas ratio of the trapped vortex area and the main combustion area can be flexibly adjusted, and the aims of trapped vortex combustion high-efficiency combustion and low pollution emission can be achieved.
The existing trapped vortex combustion chamber is mostly of an inward concave cavity structure, the combustion reaction area and the area of the existing trapped vortex combustion chamber are limited, the regulation and control of classified and partitioned combustion are not facilitated, and the combustion efficiency and the pollutant discharge efficiency are low.
SUMMERY OF THE UTILITY MODEL
In view of the above, there is a need to provide a trapped vortex combustor with a combined inner and outer cavity configuration.
The trapped vortex combustor comprises a diffuser, a combustor shell, an oil conveying pipe, an igniter and a flame tube with the combined concave cavity structure, wherein the combustor shell is connected with the diffuser; the oil delivery pipe comprises a main oil pipe, annular oil pipes and thin oil pipes, the oil delivery pipe is of a tubular structure, the main oil pipes are bendable metal pipes, the number of the oil delivery pipes is 2-6, and the oil delivery pipes are uniformly distributed on the annular oil pipes in the circumferential direction; the flame tube with the cavity combination structure comprises an inner channel inlet, an inner cavity inclined section, a mixing hole in the inner cavity inclined section, an igniter mounting through hole, an inner cavity horizontal section, an inner and outer cavity shared vertical section, a public vertical section upper through hole, an outer cavity horizontal section, an outer cavity inclined section, an outer cavity, a fixed connecting rod and an inner cavity, wherein the outer cavity is formed by enclosing the outer cavity inclined section, the outer cavity horizontal section and the inner and outer cavity shared vertical section, and the inner cavity is formed by enclosing the inner cavity inclined section, the inner cavity horizontal section and the inner cavity vertical section.
The oil pipe is a bent metal pipe, the number of the thin oil pipes is 8-16, the thin oil pipes are circumferentially and uniformly arranged on the annular oil pipe, the number of the annular oil pipes is 1, and the installation included angle of the main oil pipe and the thin oil pipes on the annular oil pipe can be 90-160 degrees.
The inner and outer cavity combined flame tube is fixedly connected with the combustion chamber shell through the fixed connecting rods, the number of the fixed connecting rods is 2-4, and one end of each fixed connecting rod is fixed on the horizontal section of the inner cavity, so that the inner and outer cavity combined flame tube is positioned in the center of the combustion chamber shell.
The number of the igniters is 2, the two igniters are arranged on the horizontal section of the inner concave cavity, and the installation included angle between the two igniters is 90-180 degrees.
Wherein the included angle between the inclined section of the inner concave cavity and the horizontal section of the inner concave cavity is 110-160 degrees.
The mixing holes in the inclined section of the inner concave cavity are 8-16 in number, the mixing holes are uniformly distributed on the inclined section of the concave cavity in the circumferential direction, and the diameter of the ring of the mixing holes in the circumferential direction is consistent with the ring diameter of the annular oil pipe.
The number of the igniter mounting through holes in the horizontal section of the inner concave cavity is 1-2, and the number of the igniter mounting through holes is consistent with the number of the igniters.
Wherein the included angle between the horizontal segment of the outer concave cavity and the inclined segment of the outer concave cavity is 110-160 degrees.
Wherein the height of the outer cavity inclined section is less than the diameter of the inner cavity horizontal section, and the height of the outer cavity inclined section is greater than 1/2 of the diameter of the cavity horizontal section.
And 2-3 circles of through holes are radially arranged on the common vertical section of the inner concave cavity and the outer concave cavity, the number of the through holes in each circle is 8-16, the through holes in two adjacent circles are arranged in a staggered manner, and part of oil pipes in the thin oil pipes extend to the outer concave cavity through the through holes in the common vertical section.
The utility model provides an inside and outside cavity combination configuration standing vortex combustor designs into inside and outside cavity combination configuration form with traditional straight section of thick bamboo flame tube, so for conventional standing vortex combustor, the utility model discloses a standing vortex combustor has effectively utilized outer cavity structure to increased the low-speed mixing space and the combustion area of fuel with the air, be of value to the combustion efficiency who improves fuel. On the other hand, because the inner concave cavity and the outer concave cavity share the vertical section, a plurality of through holes are designed, so that the flow and the heat exchange between the inner concave cavity and the outer concave cavity are facilitated. When fuel is mainly injected to the inner concave cavity, an oil-rich area is formed in the inner concave cavity, the fuel flows into the outer concave cavity through the through holes in the common vertical section and is mixed with air to form a lean combustion area, and therefore zoned combustion is naturally formed, the temperature distribution in the combustion chamber is relatively uniform, a local high-temperature area is not formed, and the formation of pollutants such as nitrogen oxides can be effectively inhibited. Furthermore, the utility model discloses still can expand to be including outer cavity oil spout simultaneously to be used for aeroengine cart operating condition. Under the condition, because a large number of through holes are formed in the inner concave cavity and the outer concave cavity, the two concave cavities have continuous heat and mass exchange, and the device is very beneficial to balancing the temperature in the combustion chamber.
Drawings
In order to more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly described below, and obviously, the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained according to the drawings without creative efforts for those skilled in the art.
Fig. 1 is a schematic view of an overall structure of an internal and external cavity combined trapped vortex combustor according to an embodiment of the present invention;
FIG. 2 is a schematic view of an oil pipe structure in a trapped vortex combustor with a combined configuration of an inner cavity and an outer cavity according to an embodiment of the present invention;
FIG. 3 is a schematic structural view of a flame tube with a cavity combination configuration in a trapped vortex combustor with an inner cavity combination configuration and an outer cavity combination configuration provided by an embodiment of the present invention;
the names corresponding to the reference numbers in the drawings are as follows: 1-diffuser, 2-combustor shell, 3-oil delivery pipe, 301-main oil pipe, 302-annular oil pipe, 303-fine oil pipe, 4-igniter, 5-concave cavity combined flame tube, 501-inner channel inflow port, 502-inner concave cavity inclined section, 503 inner concave cavity inclined section mixing hole, 504-igniter mounting through hole, 505-inner concave cavity horizontal section, 506-inner and outer concave cavity shared vertical section, 507-common vertical section through hole, 508-outer concave cavity horizontal section, 509-outer concave cavity inclined section, 510-outer concave cavity, 511-fixed connecting rod and 512-inner concave cavity.
Detailed Description
The following is a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations are also considered as the protection scope of the present invention.
An inside and outside concave cavity combined type trapped vortex combustor is shown in figures 1 to 3, and comprises a diffuser 1, a combustor shell 2, an oil delivery pipe 3, an igniter 4 and an inside and outside concave cavity combined type flame tube 5; the combustion chamber housing 2 is connected to a diffuser 1. The oil delivery pipe 3 comprises a main oil pipe 301, an annular oil pipe 302 and a thin oil pipe 303, the main oil pipe 301 and the thin oil pipe 303 are bendable metal pipes, so that the actual assembly position can be adjusted conveniently, and the main oil pipe 301 and the thin oil pipe 303 are connected with the annular oil pipe 302.
The flame tube 5 with the combined inner and outer concave cavities has a cylindrical structure, is connected with the combustion chamber shell through the fixed connecting rod 511 and is arranged at the center of a combustion chamber flow passage. The inner and outer concave cavity combined type flame tube 5 divides the main air flow entering from the diffuser 1 into an inner channel flow and an outer channel flow, wherein the inner channel flow enters the interior of the flame tube 5 from the inner channel inflow port 501. The inner and outer cavity combined flame tube 5 comprises an inner cavity 512, an outer cavity 510 and a fixed connecting rod 511, wherein the inner cavity 512 and the outer cavity 510 share a vertical section 506.
The inner concave cavity 512 is enclosed by the inner concave cavity inclined section 502, the inner concave cavity horizontal section 505 and the inner concave cavity vertical section 506; the outer cavity is bounded by the common vertical segment 506, the outer cavity horizontal segment 508, and the outer cavity diagonal segment 509. The inclined section 502 of the inner concave cavity is provided with the mixing holes 503 which are uniformly distributed in the circumferential direction and used for the penetration of the thin pipeline 303 and the entrance of partial outer channel flow, and the diameter of the ring of the mixing holes 503 which are arranged in the circumferential direction is consistent with the diameter of the ring of the annular oil pipe 302. The horizontal section 505 of the concave cavity is provided with a through hole for mounting the igniter 4. The inner and outer cavity common vertical section 506 is provided with the through hole 507.
In the embodiment of the present invention, the first and second,
the number of the main oil pipes 301 is 2-6, and the main oil pipes are uniformly distributed on the annular oil pipe 302 in the circumferential direction.
The number of the annular oil pipes is 1, and the ring diameter is consistent with the arrangement circumference diameter of the mixing hole 503.
The number of the igniters is 1-2.
The number of the thin oil pipes 303 is 8-16, the thin oil pipes are uniformly distributed on the annular oil pipe 302 in the circumferential direction, and the installation included angle between the main oil pipe and the thin oil pipes can be 90-160 degrees.
The number of the mixing holes 503 of the inclined section of the inner concave cavity can be 8-16, the specific number is consistent with the number of the thin oil pipes 303, and the mixing holes 503 are uniformly distributed on the inclined section 502 of the concave cavity in the circumferential direction.
The angle between the inclined section 502 of the inner concave cavity and the horizontal section 505 of the inner concave cavity can be 110-160 degrees.
The number of the igniter mounting through holes 504 on the horizontal section of the inner concave cavity is 1-2, and the number of the igniter mounting through holes is practically consistent with that of the igniters. When the number of the igniters is 2, the installation included angle can be 90-180 degrees.
The fixed connecting rods 511 are arranged on the horizontal section 505 of the concave cavity, the number of the fixed connecting rods is 2-4, the fixed connecting rods are uniformly distributed in the circumferential direction, and the fixed connecting rods are used for connecting the combustion chamber shell to fix the multi-cavity flame tube.
The inner and outer concave cavity common vertical section 506 is provided with through holes 507, specifically, 2-3 circles of through holes are uniformly distributed in the circumferential direction in the radial direction of the vertical section 506, each circle of through holes is 8-16, and two adjacent circles of through holes are arranged in a staggered manner.
The outer cavity horizontal segment 508 and the outer cavity angled segment 509 may be angled at 110-160 degrees.
The ratio of the diameter of the outer cavity horizontal segment 508 to the diameter of the inner cavity horizontal segment 505 may be 0.3-0.7.
The outer cavity angled section 509 has a height 1/2 that is less than the diameter of the inner cavity horizontal section 505 but greater than the diameter of the cavity horizontal section 505.
The utility model discloses a theory of operation does: the main flow air enters the combustion chamber through the diffuser, and flows under the action of the flame tube with the combined structure of the inner concave cavity and the outer concave cavity into two paths: inner channel flow and outer channel flow. When the inner and outer channel flows respectively flow through the inner and outer cavities, a vortex structure is formed in the cavity under the shearing action. And then an oil way is opened, fuel oil is converged into the annular oil pipe through the main oil pipe and then is sprayed into the inner concave cavity through the thin oil pipe, meanwhile, part of the outer channel flows through the mixing holes on the inclined section of the inner concave cavity to enter the inner concave cavity and be mixed with the sprayed fuel oil, and at the moment, the igniter is started to ignite. The fuel oil can not be completely combusted in the inner concave cavity, one part of the fuel oil is mixed with the channel flow and continuously combusted, and the other part of the fuel oil enters the outer concave cavity through the through hole in the shared vertical section and continuously combusted. The through holes on the shared vertical section are beneficial to balancing the temperature distribution in the combustion chamber, thereby improving the combustion efficiency and reducing the pollutant emission.
The utility model provides an inside and outside cavity combination configuration resides in vortex combustion chamber, specific working process is:
when the engine works, the main flow air flows through the diffuser 1 and enters the combustion chamber shell 2, the inner and outer concave cavity combined flame tube structure 5 divides the entering main flow air into two parts, and the two parts respectively enter the inner channel through the inner channel inflow port 501 and enter the outer channel of the flame tube 5 through the channel between the combustion chamber shell 2 and the flame tube 5. And then oil supply is started, oil is converged into the annular oil pipe 302 through the multi-path main oil pipe 301, and then is sprayed into the inner concave cavity through the thin oil pipe, the oil is firstly mixed with air entering from the mixing hole 503 at the inclined section of the inner concave cavity after being sprayed, the igniter 4 is started to ignite, and then unburned oil is continuously mixed with the air entering from the inner channel, so that vortex combustion is formed in the inner concave cavity 512. Because fuel is mainly injected into the inner concave cavity, the oil-gas ratio is relatively high, and a rich combustion area is formed naturally. One part of the re-entrant rich zone continues to burn with air in the inner channel and the other part flows into the outer re-entrant chamber 510 through the common vertical section through-holes 507. Since the air passing through the outer flow passage flows through the outer cavity 510, it will also form a vortex structure in the outer cavity 510 under the shearing action, and continue to react with the fuel flowing from the rich region of the inner cavity 512. And finally, discharging combustion products in the inner channel and the outer channel together through an outlet of the combustion chamber.
The utility model provides an inside and outside cavity combination configuration standing vortex combustor designs into inside and outside cavity combination configuration form with traditional straight section of thick bamboo flame tube, so for conventional standing vortex combustor, the utility model discloses a standing vortex combustor has effectively utilized outer cavity structure to increased the low-speed mixing space and the combustion area of fuel with the air, be of value to the combustion efficiency who improves fuel. On the other hand, because the inner concave cavity and the outer concave cavity share the vertical section, a plurality of through holes are designed, so that the flow and the heat exchange between the inner concave cavity and the outer concave cavity are facilitated. When fuel is mainly injected to the inner concave cavity, an oil-rich area is formed in the inner concave cavity, the fuel flows into the outer concave cavity through the through holes in the common vertical section and is mixed with air to form a lean combustion area, and therefore zoned combustion is naturally formed, the temperature distribution in the combustion chamber is relatively uniform, a local high-temperature area is not formed, and the formation of pollutants such as nitrogen oxides can be effectively inhibited. Furthermore, the utility model discloses still can expand to be including outer cavity oil spout simultaneously to be used for aeroengine cart operating condition. Under the condition, because a large number of through holes are formed in the inner concave cavity and the outer concave cavity, the two concave cavities have continuous heat and mass exchange, and the device is very beneficial to balancing the temperature in the combustion chamber.
The above embodiments only express the specific embodiments of the present invention, and the description thereof is specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several changes and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.
Claims (10)
1. The utility model provides an inside and outside cavity combination configuration standing vortex combustor which characterized in that: the trapped vortex combustor comprises a diffuser (1), a combustor shell (2), an oil delivery pipe (3), an igniter (4) and a flame tube (5) with a concave cavity combined structure, wherein the combustor shell (2) is connected with the diffuser (1); the oil delivery pipe (3) comprises a main oil pipe (301), annular oil pipes (302) and fine oil pipes (303), the oil delivery pipe (3) is of a tubular structure, the main oil pipe (301) is a bendable metal pipe, the number of the oil delivery pipes (3) is 2-6, and the oil delivery pipes are circumferentially and uniformly arranged on the annular oil pipes (302); the flame tube (5) with the cavity combination structure comprises an inner channel inlet (501), an inner cavity inclined section (502), a mixing hole (503) in the inner cavity inclined section, an igniter installation through hole (504), an inner cavity horizontal section (505), an inner and outer cavity common vertical section (506), a common vertical section upper through hole (507), an outer cavity horizontal section (508), an outer cavity inclined section (509), an outer cavity (510), a fixed connecting rod (511) and an inner cavity (512), wherein the outer cavity (510) is formed by enclosing the outer cavity inclined section (509), the outer cavity horizontal section (508) and the inner and outer cavity common vertical section (506), and the inner cavity (512) is formed by enclosing the inner cavity inclined section (502), the inner cavity horizontal section (505) and the inner and outer cavity common vertical section (506).
2. The trapped vortex combustor of claim 1, wherein: the thin oil pipes (303) are bent metal pipes, the number of the thin oil pipes (303) is 8-16, the thin oil pipes are circumferentially and uniformly arranged on the annular oil pipe (302), the number of the annular oil pipes (302) is 1, and the installation included angle of the main oil pipe (301) and the thin oil pipes (303) on the annular oil pipe (302) can be 90-160 degrees.
3. The trapped vortex combustor of claim 1, wherein: inner and outer cavity combination configuration flame tube (5) pass through fixed connecting rod (511) with combustion chamber casing (2) are connected fixedly, the quantity that sets up of fixed connecting rod (511) is 2 to 4, fixed connecting rod (511) one end is all fixed on inner cavity horizontal segment (505), make inner and outer cavity combination configuration flame tube (5) are located combustion chamber casing (2) center.
4. The trapped vortex combustor of claim 1, wherein: the number of the igniters (4) is 2, the two igniters (4) are arranged on the horizontal section (505) of the concave cavity, and the installation included angle between the two igniters (4) is 90-180 degrees.
5. The trapped vortex combustor of claim 1, wherein: the included angle between the inclined section (502) of the inner concave cavity and the horizontal section (505) of the inner concave cavity is 110-160 degrees.
6. The trapped vortex combustor of claim 5, wherein: the number of the mixing holes (503) in the inner concave inclined section (502) is 8-16, the number of the mixing holes (503) is consistent with the number of the thin oil pipe (303), the mixing holes (503) are uniformly distributed on the concave inclined section (502) in the circumferential direction, and the diameter of the ring of the mixing holes (503) in the circumferential direction is consistent with the ring diameter of the annular oil pipe (302).
7. The trapped vortex combustor of claim 6, wherein: the number of the igniter mounting through holes (504) in the horizontal section (505) of the inner concave cavity is 1-2, and the number of the igniter mounting through holes (504) is consistent with the number of the igniters (4).
8. The trapped vortex combustor of claim 7, wherein: the included angle between the horizontal section (508) of the outer concave cavity and the inclined section (509) of the outer concave cavity is 110-160 degrees.
9. The trapped vortex combustor of claim 8, wherein: the height of the outer cavity inclined section (509) is smaller than the diameter of the inner cavity horizontal section (505), and the height of the outer cavity inclined section (509) is larger than 1/2 of the diameter of the cavity horizontal section (505).
10. The trapped vortex combustor of claim 9, wherein: 2-3 circles of through holes (507) are radially arranged on the inner and outer cavity shared vertical section (506), the number of the through holes (507) in each circle is 8-16, two adjacent circles of the through holes (507) are arranged in a staggered mode, and part of the thin oil pipe (303) extends to the outer cavity (510) through the through holes in the inner and outer cavity shared vertical section (506).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022557404.4U CN213513985U (en) | 2020-11-09 | 2020-11-09 | Inside and outside cavity combination configuration standing vortex combustor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022557404.4U CN213513985U (en) | 2020-11-09 | 2020-11-09 | Inside and outside cavity combination configuration standing vortex combustor |
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| Publication Number | Publication Date |
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| CN213513985U true CN213513985U (en) | 2021-06-22 |
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| CN202022557404.4U Active CN213513985U (en) | 2020-11-09 | 2020-11-09 | Inside and outside cavity combination configuration standing vortex combustor |
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| CN (1) | CN213513985U (en) |
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