CN113587147B

CN113587147B - Ceramic base flame tube positioning structure

Info

Publication number: CN113587147B
Application number: CN202110857172.0A
Authority: CN
Inventors: 戴金鑫; 郎旭东; 陈智莹; 刘丽娟; 张荣幸; 杨大伟
Original assignee: Hunan Aviation Powerplant Research Institute AECC
Current assignee: Hunan Aviation Powerplant Research Institute AECC
Priority date: 2021-07-28
Filing date: 2021-07-28
Publication date: 2022-05-17
Anticipated expiration: 2041-07-28
Also published as: CN113587147A

Abstract

The invention discloses a ceramic-based flame tube positioning structure, which belongs to the technical field of aero-engines and comprises a flame tube head integrally formed with a flame tube inner ring, wherein the flame tube head comprises a flange arranged at the outer edge of the flame tube head and a concave spigot close to the flange; the inner ring of the flame tube comprises a small bent tube, the tail end of the small bent tube is provided with an annular groove, and the inner ring of the flame tube is lapped with the inner casing of the combustion chamber through the annular groove; a plurality of locating pins are evenly distributed on the outer casing of the combustion chamber in the circumferential direction, and a plurality of locating pin seats matched with the locating pins are evenly distributed on the outer ring surface of the flame tube and used for supporting the flame tube. Under the working state, the space requirement required by thermal expansion of the positioning pin, the inner case of the combustion chamber and the outlet support ring can be met through the reserved gap between the positioning pin and the hole bottom of the positioning pin seat and the gap between the reserved positioning pin and the annular groove. In a cold state or a hot state, the inner casing and the outlet support ring in the combustion chamber can also play a role in auxiliary support of the wall surface of the flame tube.

Description

Ceramic base flame tube positioning structure

Technical Field

The invention belongs to the technical field of aero-engines, and particularly relates to a ceramic-based flame tube positioning structure.

Background

With the development of engine technology, the working temperature of the flame tube of the combustion chamber is gradually increased, and the temperature resistance of the flame tube material is further improved on the basis of meeting the requirements of light weight, high reliability, long service life and the like. The ceramic matrix composite material is the best way to improve the temperature resistance of the engine combustion chamber component and the engine efficiency by replacing the traditional high-temperature alloy material.

The ceramic matrix composite material is a composite material compounded by taking ceramic as a matrix and various fibers, and has excellent performances of high temperature resistance, high strength, high rigidity, light relative weight, corrosion resistance and the like. However, because of the great difference in thermal expansion properties between the ceramic matrix composite and the metal material, the problems of the ceramic matrix composite component mounting, the cold and hot state coordination, and the like need to be solved. Therefore, research and development of a reliable positioning structure are of great significance to the application of the composite material in the field of engine combustion chambers.

The Chinese patent with the application number of 201210195221.X discloses a fixing structure of a ceramic-based flame tube wall, which comprises a high-temperature alloy flame tube head, inner and outer walls of a ceramic-based composite flame tube, inner and outer support rings made of metal materials and positioning pins; the flame tube is fixed in a split manner, the head of the flame tube is connected with the outer casing of the combustion chamber through a positioning pin, the tail ends of the inner wall and the outer wall of the flame tube are connected with the inner supporting ring and the outer supporting ring through rivets, the inner supporting ring and the outer supporting ring are installed on the outer casing of the combustion chamber through bolts, the front ends of the inner wall and the outer wall of the flame tube are in lap joint with the annular groove of the head, and the annular groove can provide the movement allowance of the inner wall and the outer wall of the flame tube during radial cold and hot changes. Although the application and connection of the ceramic matrix composite material on the flame tube of the combustion chamber are basically realized by the flame tube fixing structure, the head of the flame tube is still made of a metal material, the temperature resistance of the head of the flame tube is not improved, and the problems of positioning and connection of the flame tube made of the ceramic matrix composite material cannot be solved.

The head of the flame tube is made of metal materials, so that the temperature resistance of the wall surface of the head is limited, and the positioning and connection of the full ceramic matrix composite flame tube cannot be realized by the conventional structural scheme; the fixing mode of the sub-components is difficult to ensure the relative position relation of the inner wall and the outer wall of the flame tube.

Accordingly, the present invention is directed to a ceramic-based liner positioning structure that solves the above-mentioned problems of the prior art.

Disclosure of Invention

The invention aims to provide a positioning structure of a ceramic-based flame tube aiming at the defects of the prior art, which can realize the positioning and connection of the flame tube made of a ceramic-based composite material and a metal casing and meet the use requirements of the ceramic-based flame tube in a high-temperature-rise high-power-to-weight-ratio combustion chamber.

According to one aspect of the invention, the ceramic-based flame tube positioning structure comprises a combustion chamber outer casing, a combustion chamber inner casing, a diffuser, a flame tube outer ring and a flame tube inner ring, wherein the outer edge of the diffuser is fixed on the combustion chamber outer casing, the inner edge of the diffuser is fixedly provided with an outlet support ring, a flame tube is arranged in a region between the combustion chamber outer casing and the combustion chamber outer casing as well as between the combustion chamber outer casing and the diffuser, the flame tube comprises a flame tube outer ring and a flame tube inner ring, the flame tube head is integrally formed with the flame tube inner ring, and the flame tube head comprises a flange arranged on the outer edge of the flame tube head and a concave spigot close to the flange;

the flame tube inner ring and the flame tube outer ring are provided with annular grooves and are respectively in lap joint with a casing and an outlet support ring in the combustion chamber, the front end of the flame tube outer ring is provided with a male spigot matched with a female spigot for centering the flame tube inner ring and the flame tube outer ring, a plurality of connection lug pieces are uniformly distributed on the annular surface of the flame tube outer ring close to the male spigot, the connection lug pieces and the flange are fixed through bolts, and the flame tube outer ring is in lap joint with the outlet support ring through the annular grooves.

According to the preferred embodiment of the invention, the outer flame tube ring, the inner flame tube ring, the flame tube head, the positioning pin seat, the connecting lug and the annular groove are all made of ceramic matrix composite materials.

According to the preferred embodiment of the invention, the positioning pin is in clearance fit with the positioning pin seat, and the positioning pin is spaced from the bottom of the hole of the positioning pin seat and used for radial expansion allowance of the flame tube.

According to the preferred embodiment of the invention, the female spigot is annular, and the annular center of the female spigot is coincident with the axial center of the inner ring of the flame tube.

According to a preferred embodiment of the present invention, in a cold state of the combustor basket, an axial gap along an axial direction of the combustor basket and a radial gap close to an outer ring of the combustor basket exist at a joint of the casing in the combustor basket and the annular groove, so as to meet a space requirement required by thermal expansion of the casing in the combustor basket.

According to the preferred embodiment of the invention, in a cold state of the combustor basket, a gap along the axial direction of the combustor basket and a gap close to the axial center of the combustor basket exist at the joint of the outlet support ring and the annular groove, so that the space requirement required by thermal expansion of the combustor outer casing, the diffuser and the outlet support ring is met.

According to the preferred embodiment of the invention, the annular groove is formed in a way that one side edge A of the annular groove is preformed firstly, the other side edge B is woven and formed together with the inner ring of the flame tube, and the side edge A is wedged into the side edge B in the forming process of the side edge B and is deposited in a secondary superposition mode, so that the annular groove is formed finally.

According to a preferred embodiment of the present invention, the positioning pin includes a stop portion and an insertion portion penetrating through the combustion chamber outer casing, and a contact portion of the insertion portion and a sidewall of the positioning pin seat is an arc surface.

According to a preferred embodiment of the present invention, the positioning pin is provided with a bolt hole along an axial direction, a reinforcing ring for increasing mechanical strength is provided at a joint of the combustion chamber outer casing and the positioning pin, and the positioning pin is fixed to the combustion chamber outer casing by a bolt.

Compared with the prior art, the invention has the beneficial effects that:

the inner ring of the flame tube made of the ceramic matrix composite material and the outer ring of the flame tube made of the ceramic matrix composite material are centered and fixed together through the positioning pin, the outlet support ring and the inner casing of the combustion chamber are respectively overlapped with the corresponding annular groove made of the ceramic matrix composite material, and under the working state, the space requirement required by the thermal expansion of the positioning pin, the inner casing of the combustion chamber and the outlet support ring can be met through the reserved gap between the positioning pin and the hole bottom of the positioning pin seat and the gap between the reserved positioning pin and the annular groove. In addition, the casing and the outlet support ring in the combustion chamber can also play a role of auxiliary support on the wall surface of the flame tube no matter in a cold state or a hot state, so that the long-term reliable stable work of the flame tube is very favorable, the integral positioning of the ceramic-based flame tube is realized, and the centering of the head part of the flame tube, the inner wall of the flame tube and the outer wall of the flame tube is ensured; by adopting the positioning structure, the head of the flame tube can be made of ceramic matrix composite materials, thereby improving the temperature resistance of the flame tube, reducing the cooling gas consumption of the flame tube and simultaneously playing a role in reducing the weight of the flame tube.

Drawings

In order to facilitate understanding for those skilled in the art, the present invention will be further described with reference to the accompanying drawings.

FIG. 1 is a schematic view of the overall structure of the present invention;

fig. 2 is an enlarged view of region a in fig. 1.

In the figure: 1. a combustion chamber outer casing; 2. a combustion chamber inner casing; 3. a diffuser; 4. positioning pins; 5. an outer ring of the flame tube; 6. an inner ring of the flame tube; 7. a concave spigot; 8. positioning a pin boss; 9. connecting a lug plate; 10. an annular groove; 11. an outlet support ring; 12. a flame tube head; 13. the inner wall of the flame tube; 14. a small bent pipe; 15. a flange; 16. a large bent pipe; 17. and (4) a convex spigot.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention are further described in detail below by way of examples with reference to the accompanying drawings. In the specification, the same or similar reference numerals denote the same or similar components. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the general inventive concept of the present invention and should not be construed as limiting the invention.

Furthermore, in the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the disclosure. It may be evident, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in schematic form in order to simplify the drawing.

Referring to fig. 1-2, according to a general technical concept of the present invention, a preferred embodiment of the present invention discloses a specific technical solution of a ceramic-based liner positioning structure as follows:

fig. 1 shows a positioning structure of a ceramic-based liner, which includes a combustion chamber outer casing 1, a combustion chamber inner casing 2, a diffuser 3, a positioning pin 4, a ceramic-based composite liner outer ring 5, a ceramic-based composite liner inner ring 6, a female spigot 7, a ceramic-based composite positioning pin seat 8, a ceramic-based composite connection lug 9, a ceramic-based composite annular groove 10, and a metal outlet support ring 11.

The inner flame tube ring 6 is the inner boundary of the combustion zone and comprises a flame tube head 12 and a flame tube inner wall 13, in particular, for an annular backflow combustor, a small elbow 14 of the inner flame tube ring 6 and the outer edge of the inner flame tube ring 6 are designed into a flange 15 structure, and bolt holes are arranged on the flange for connecting with the outer flame tube ring 5. A female spigot 7 is designed near the flange 15, and the female spigot 7 can be formed by machining and used for centering with the outer ring 5 of the flame tube. At the outlet of the inner ring 6 of the flame tube, the annular groove 10 of the ceramic matrix composite material is pre-formed and then fixed on the inner ring 6 of the flame tube. The inner liner ring 6 of ceramic matrix composite is connected with the inner casing 2 of the combustion chamber made of metal material through the annular groove 10.

The outer liner ring 5 is the outer boundary of the combustion zone, and in particular, for an annular reverse flow combustor, the large elbow 16 of the outer liner ring 5. The front end of the outer flame tube ring 5 is provided with a section of annular convex spigot 17, and the convex spigot 17 is matched with the concave spigot 7 positioned on the inner flame tube ring 6 to center the inner flame tube ring 6 and the outer flame tube ring 5. A plurality of connection lug pieces 9 are uniformly distributed on the annular surface of the flame tube outer ring 5 close to the male spigot 17, the connection lug pieces 9 made of the ceramic matrix composite are pre-formed and then fixed on the flame tube outer ring 5, and the connection lug pieces 9 and the flange 15 are fixed through bolts, so that the flame tube inner ring 6 made of the ceramic matrix composite and the flame tube outer ring 5 made of the ceramic matrix composite are connected into a whole. A plurality of positioning pin seats 8 are uniformly distributed at the position, close to the head, of the outer ring 5 of the flame tube, and the positioning pin seats 8 made of the ceramic matrix composite material are pre-formed and then fixed on the outer ring 5 of the flame tube. The inner flame tube ring 6 and the outer flame tube ring 5 made of the ceramic matrix composite are connected into a whole through bolts, and then are centered and connected with the outer combustion chamber casing 1 through the positioning pin 4, and the positioning pin 4 is installed on the outer combustion chamber casing 1 through bolts. At the outlet of the outer ring 5 of the liner, the annular groove 10 made of the ceramic matrix composite is preformed and then fixed on the outer ring 5 of the liner, and the outer ring 5 of the liner made of the ceramic matrix composite is connected with an outlet support ring 11 made of a metal material through the annular groove 10. The outlet support ring 11 is fixed to the diffuser 3 or the combustion chamber outer casing 1 by bolts.

Because the difference of the linear expansion coefficients of the materials is large, the expansion amount of the ceramic matrix composite is very small compared with that of a metal material under the condition of temperature rise, so that in order to improve the cold and hot state matching performance of the combustion chamber component, in a cold state, the inner flame tube ring 6 of the ceramic matrix composite and the outer flame tube ring 5 of the ceramic matrix composite realize the centering and fixing of the ceramic matrix flame tube through the positioning pin 4, the outlet support ring 11 and the combustion chamber casing 2 are respectively overlapped with the corresponding annular groove 10 of the ceramic matrix composite, and in a working state, the space requirement required by the thermal expansion of the positioning pin 4, the combustion chamber casing 2 and the outlet support ring 11 can be met through the reserved gap between the positioning pin 4 and the hole bottom of the positioning pin seat 8 and the reserved gap between the annular grooves 10. In addition, the combustion chamber inner casing 2 and the outlet support ring 11 can also play a role of auxiliary support for the wall surface of the flame tube no matter in a cold state or a hot state, and are very favorable for long-term reliable stable operation of the flame tube.

In particular, excessive wear occurs in order to prevent the positioning pin 4 from operating for a long time, thereby causing failure of the positioning structure. The positioning pin 4 can also be coated at the contact part of the positioning pin seat 8 of the ceramic matrix composite material, or nitrided to form a nitriding layer through nitriding treatment, or manufactured by combining two materials, for example, the head part of the positioning pin 4 in contact with the positioning pin seat 8 is manufactured by the ceramic matrix material, and the mounting part with the bolt hole is manufactured by the metal material.

The structure of the combustion chamber can be divided into direct current, backflow and other structural forms. For the direct-flow combustor, the inner flame tube ring 6 is of a structure without the small elbow 14, and only the flame tube of the backflow combustor has the small elbow 14. This patent ceramic base flame tube location structure not only is applicable to the backflow flame tube, also can be used to the location of direct current flame tube.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a ceramic base flame tube location structure, includes combustion chamber outer casing (1), combustion chamber inner casing (2) and diffuser (3), diffuser (3) outer fringe is fixed in combustion chamber outer casing (1) inboardly, diffuser (3) inner edge is fixed with exit support ring (11), set up the flame tube in the combustion chamber between casing (2) and the combustion chamber outer casing (1) and diffuser (3) in the region, the flame tube includes flame tube outer loop (5) and flame tube inner ring (6), its characterized in that still includes:

the flame tube head (12) is integrally formed with the inner ring (6) of the flame tube, and the flame tube head (12) comprises a flange (15) arranged on the outer edge of the flame tube head and a concave spigot (7) close to the flange (15);

the positioning pins (4) are uniformly distributed on the outer casing (1) of the combustion chamber in the circumferential direction, and a plurality of positioning pin seats (8) matched with the positioning pins (4) are uniformly distributed on the ring surface of the outer ring (5) of the flame tube and used for supporting the flame tube;

inner ring of flame tube (6) and outer ring of flame tube (5) are equipped with ring channel (10) and respectively with combustion chamber inner casing (2) and export support ring (11) overlap joint, the front end of outer ring of flame tube (5) is equipped with protruding tang (17) with concave tang (7) matched with for inner ring of flame tube (6) and outer ring of flame tube (5) are centering, are close to a plurality of connection lug piece (9) of equipartition on outer ring of flame tube (5) the anchor ring of protruding tang (17), connection lug piece (9) pass through the bolt fastening with flange (15), outer ring of flame tube (5) are through ring channel (10) and export support ring (11) overlap joint.

2. The ceramic-based flame tube positioning structure according to claim 1, wherein the outer flame tube ring (5), the inner flame tube ring (6), the flame tube head (12), the positioning pin seat (8), the connecting lug (9) and the annular groove (10) are all made of ceramic-based composite materials.

3. The ceramic-based flame tube positioning structure according to claim 2, wherein the positioning pin (4) is in clearance fit with the positioning pin seat (8), and the positioning pin (4) is spaced from the bottom of the hole of the positioning pin seat (8) for providing a radial expansion allowance for the flame tube.

4. The ceramic-based flame tube positioning structure according to claim 1, wherein the female spigot (7) is annular, and the annular center of the female spigot (7) coincides with the axial center of the inner flame tube ring (6).

5. The positioning structure of the ceramic-based flame tube according to claim 1, wherein the overlap joint of the inner casing (2) and the annular groove (10) of the combustion chamber has an axial gap along the axial direction of the flame tube and a radial gap close to the outer ring (5) of the flame tube in the cold state of the flame tube, so as to meet the space requirement for the thermal expansion of the inner casing (2) of the combustion chamber.

6. The positioning structure of the ceramic-based flame tube according to claim 1, wherein the overlap joint of the outlet support ring (11) and the annular groove (10) of the flame tube has a gap along the axial direction of the flame tube and a gap close to the axial center of the flame tube in the cold state of the flame tube, so as to meet the space requirement for thermal expansion of the outer casing (1), the diffuser (3) and the outlet support ring (11) of the combustion chamber.

7. The ceramic-based liner positioning structure according to any one of claims 5-6, wherein the annular groove (10) is formed in a way that one side A of the annular groove (10) is preformed, the other side B is woven and formed together with the liner inner ring (6), and the side A is wedged into the side B in the process of forming the side B and is deposited through secondary superposition, so that the annular groove (10) is formed finally.

8. The positioning structure of the ceramic-based flame tube according to claim 1, wherein the positioning pin (4) comprises a stop part and an insertion part penetrating through the outer casing (1) of the combustion chamber, and the contact part of the insertion part and the side wall of the positioning pin seat (8) is an arc surface.

9. The positioning structure of the ceramic-based flame tube according to claim 8, wherein the positioning pin (4) is provided with a bolt hole along the axial direction, a reinforcing ring for increasing the mechanical strength is arranged at the joint of the combustion chamber casing (1) and the positioning pin (4), and the positioning pin (4) is fixed on the combustion chamber casing (1) through a bolt.