CN114413284A

CN114413284A - Special-shaped swirler matched with head of annular combustion chamber

Info

Publication number: CN114413284A
Application number: CN202111630707.7A
Authority: CN
Inventors: 赵自强; 雷鸣; 凌文辉; 王云雷; 何悟; 王伟利; 刘易安; 薛永广
Original assignee: Beijing Power Machinery Institute
Current assignee: Beijing Power Machinery Institute
Priority date: 2021-12-28
Filing date: 2021-12-28
Publication date: 2022-04-29

Abstract

The invention discloses a special-shaped swirler matched with a head part of an annular combustion chamber, which comprises an inner barrel, an outer barrel, inner-stage swirler vanes (1), middle-stage swirler vanes (2), outer-stage swirler vanes (3), an inner middle venturi tube (4) and a middle outer venturi tube (5); the inner Chinese venturi (4) is sleeved outside the inner barrel, the middle and outer venturi (5) is sleeved outside the inner and middle venturi (4), the outer barrel is sleeved outside the middle and outer venturi (5), the inner-stage swirler vanes (1) are arranged between the inner barrel and the inner Chinese venturi (4), the middle-stage swirler vanes (2) are arranged between the inner and middle venturi (4) and the middle and outer venturi (5), and the outer-stage swirler vanes (3) are arranged between the middle and outer venturi (5) and the outer barrel. The special-shaped swirler has a compact structure, can achieve the purpose of matching swirler airflow with the trapezoid cross section of the flame tube, and optimizes an angular backflow area.

Description

Special-shaped swirler matched with head of annular combustion chamber

Technical Field

The invention belongs to the technical field of aero-engine combustion chambers, and relates to a special-shaped swirler matched with a head of an annular combustion chamber.

Background

Aircraft engine combustors typically contain components such as swirlers, flame tubes, and the like. The swirler is fixed at the head plate and provides a reliable backflow flow field for stable flame and efficient combustion of the combustion chamber. The typical cyclone is a single-stage cyclone, a double-stage cyclone or a multi-stage cyclone which are arranged in a concentric circle, so that the outlet of the cyclone is a circular ring type uniform airflow. A typical cyclone configuration is shown in figures 1 to 3.

For annular combustors, it is common to divide the combustor into multiple heads, i.e., one head for each swirler, depending on the number of swirlers. For a swirler, the corresponding head flame tube is in a trapezoid shape (different from the trapezoid shape, namely the trapezoid shape is high, the bottom is in an arc shape, and the shape is named as trapezoid-like shape), so that the trapezoid-like head is not matched with the circular swirler structurally. This structural mismatch has the following effect:

1. the cross section area of the outer ring part of the flame tube of the annular combustion chamber is larger than that of the inner ring part of the flame tube, and the outlet of the swirler is circular airflow with uniform circumference, so that the volume of the outer ring of the flame tube is larger than that of the inner ring. This spatial non-uniformity of volume causes the swirler to have a tendency to flow into the flame tube from the inner flame tube annulus to the outer flame tube annulus. This trend raises the difficulty of combustion organization design and outlet temperature distribution adjustment.

2. There are four angular vortices between the swirler exit and the trapezoid-like head plate, and relatively speaking, the outer annular angular vortex region (A, B) is larger than the inner annular angular vortex region (C, D). The existence of the angular vortex area easily causes the fuel and flame to roll into the angular vortex in the combustion process, and causes the combustion oscillation phenomenon, thereby bringing risks to the stable work of the combustion chamber.

3. The whole structure of the flame tube is in a trapezoid-like shape, and the corresponding main combustion holes and the corresponding mixing hole jet flow gas are also in a trapezoid-like curtain shape. The flow field at the outlet of the cyclone is annular, so that the difficulty in arrangement of jet gas of the main combustion hole and the mixing hole is increased undoubtedly, and great challenge is brought to the temperature regulation of the outlet of the combustion chamber.

4. Due to the requirement of head joint flame, the circumferential distance of the head of the flame tube is generally smaller than the radial height of the flame tube, so that the distances between the periodic surfaces on the two sides of the flame tube and the outer diameter of the swirler are smaller. When the adjacent two heads of fuel flow to the periodic surface of the flame tube, the fuel can be overlapped at the periodic surface, so that the phenomenon of local oil enrichment can occur.

Disclosure of Invention

Objects of the invention

The purpose of the invention is: the special-shaped swirler matched with the annular combustion chamber head is provided, the structure of the swirler is optimized on the basis of a typical swirler, and the transition process of the circular and flame tube trapezoidal space of the typical swirler is improved, so that the airflow of the swirler can be well matched with the flame tube trapezoidal section, the angular vortex is optimized, and the risk of combustion oscillation is reduced.

(II) technical scheme

In order to solve the technical problem, the invention provides a special-shaped swirler matched with the head of an annular combustion chamber, which comprises an inner cylinder, an outer cylinder, inner-stage swirler vanes 1, middle-stage swirler vanes 2, outer-stage swirler vanes 3, an inner middle venturi 4 and an outer middle venturi 5; the inner venturi tube 4 is sleeved outside the inner barrel, the middle venturi tube 5 is sleeved outside the inner venturi tube 4, the outer barrel is sleeved outside the middle venturi tube 5, the inner swirler vanes 1 are arranged between the inner barrel and the inner middle venturi tube 4, the middle swirler vanes 2 are arranged between the inner and middle venturi tubes 4 and the middle venturi tube 5, and the outer swirler vanes 3 are arranged between the middle and outer venturi tubes 5 and the outer barrel.

Wherein the inner and middle venturis 4 are circular.

The inner and middle venturis 4 are of a trapezoid-like structure, the trapezoid-like structure is a quadrilateral structure comprising an upper bottom, a lower bottom and two side edges, and four corners are all provided with arc chamfers.

The middle and outer venturi tube 5 is used for arranging the main combustion stage nozzles, and the cross section of the middle and outer venturi tube 5 is in a special shape between a circle and the outline of the swirler.

Wherein, the wall thickness of the middle and outer venturi tube 5 is larger than that of the inner and middle venturi tube 4.

Wherein the high profile 9 of the swirler is concentric with the central axis of the liner.

Wherein the bottom profile 10 of the swirler is concentric to the central axis of the flame tube.

Wherein, two side surfaces 6 of the swirler are respectively parallel to two periodic surfaces of the single-head flame tube.

Wherein, the junction of the high profile 9 and the bottom profile 10 of the swirler and the two side surfaces 6 is provided with a first rounding 7 and a second rounding 8.

(III) advantageous effects

The special-shaped swirler matched with the head of the annular combustion chamber, provided by the technical scheme, has a compact structure, and by adopting the special-shaped swirler, the aim of matching the airflow of the swirler with the trapezoid cross section of the flame tube can be fulfilled, and the angular backflow area is optimized.

Drawings

FIG. 1 is a schematic view of a typical head swirler application.

FIG. 2 is a schematic illustration of a typical head swirler construction.

FIG. 3 is a front view of an exemplary head swirler.

FIG. 4 is a cross-sectional view of a contoured swirler of the present invention mated to an annular combustor head.

FIG. 5 is a cross-sectional view of a contoured swirler of the present invention mated to an annular combustor head.

FIG. 6 is a schematic view of the swirler sleeve and header plate integrated.

Detailed Description

In order to make the objects, contents and advantages of the present invention clearer, the following detailed description of the embodiments of the present invention will be made in conjunction with the accompanying drawings and examples.

As shown in fig. 4 to 6, the special-shaped swirler of the invention matched with the annular combustion chamber head comprises an inner barrel, an outer barrel, inner stage swirler vanes 1, middle stage swirler vanes 2, outer stage swirler vanes 3, an inner middle venturi 4 and a middle outer venturi 5; the inner venturi tube 4 is sleeved outside the inner barrel, the middle venturi tube 5 is sleeved outside the inner venturi tube 4, the outer barrel is sleeved outside the middle venturi tube 5, the inner swirler vanes 1 are arranged between the inner barrel and the inner middle venturi tube 4, the middle swirler vanes 2 are arranged between the inner and middle venturi tubes 4 and the middle venturi tube 5, and the outer swirler vanes 3 are arranged between the middle and outer venturi tubes 5 and the outer barrel.

The inner Chinese venturi 4 can adopt a circular or trapezoid-like structure according to the requirement of combustion organization, the trapezoid-like structure is a quadrilateral structure comprising an upper bottom, a lower bottom and two side edges, and four corners all adopt arc chamfers.

The middle and outer venturi tubes 5 are used for arranging the main combustion stage nozzles, and the cross section of the middle and outer venturi tubes 5 can be designed into a special shape between the circular shape and the outline of the swirler according to the requirements of oil and gas organization.

The wall thickness of the middle and outer venturis 5 is larger than that of the inner and middle venturis 4.

The swirler high profile 9 and the swirler bottom profile 10 are concentric with the central axis of the flame tube.

Two side surfaces 6 of the cyclone are respectively parallel to two periodic surfaces of the single-head flame tube.

The joint of the cyclone high profile 9 and the bottom profile 10 and the two side surfaces 6 is provided with a first rounding 7 and a second rounding 8.

The working principle of the special-shaped swirler scheme matched with the head part of the annular combustion chamber is as follows:

1. air flows into the flame tube through the swirler, and due to the special shape of the swirler, the air inlet of the swirler at each position in space is inconsistent. The air inflow and the cross section area of the cyclone are in one-to-one correspondence, so that the air flow is spatially matched with the head trapezoid.

2. At the corners 11 and 12, because of the existence of the rounding, the flow area at the corners is slightly larger, and more air inflow can effectively fill the angular backflow area, thereby effectively avoiding the combustion oscillation phenomenon generated by combustion in the angular backflow area.

3. The working principle of the inner stage, the middle stage and the outer stage of the special-shaped cyclone is similar to that of a typical cyclone.

4. The cyclone air inlet is matched with the trapezoid cross section of the flame tube, so that the temperature adjustment of the combustion chamber opening is facilitated.

According to the technical scheme, the invention has the following remarkable characteristics:

1. two side surfaces of the cyclone are parallel to the periodic surface of the single-head flame tube.

2. The high profile and the bottom profile of the swirler are concentric with the central axis of the flame tube.

3. According to the requirement of combustion organization, the high profile, the bottom profile and the positions of two side surfaces of the swirler are reasonably designed.

4. According to the requirement of combustion organization, a main combustion stage nozzle at the middle and outer venturi is designed, so that fuel oil space distribution matched with air flow is obtained according to air flow distribution of a swirler.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. A special-shaped swirler matched with a head of an annular combustion chamber is characterized by comprising an inner barrel, an outer barrel, inner-stage swirler vanes (1), middle-stage swirler vanes (2), outer-stage swirler vanes (3), an inner middle venturi tube (4) and a middle outer venturi tube (5); the inner Chinese venturi (4) is sleeved outside the inner barrel, the middle and outer venturi (5) is sleeved outside the inner and middle venturi (4), the outer barrel is sleeved outside the middle and outer venturi (5), the inner-stage swirler vanes (1) are arranged between the inner barrel and the inner Chinese venturi (4), the middle-stage swirler vanes (2) are arranged between the inner and middle venturi (4) and the middle and outer venturi (5), and the outer-stage swirler vanes (3) are arranged between the middle and outer venturi (5) and the outer barrel.

2. The contoured swirler of claim 1, matched to an annular combustion chamber head, characterised in that the inner, middle venturi (4) is circular.

3. The special-shaped swirler matched with the annular combustion chamber head as claimed in claim 2, characterized in that the inner and middle venturis (4) are of a trapezoid-like structure, the trapezoid-like structure is of a quadrilateral structure comprising an upper bottom, a lower bottom and two side edges, and four corners are provided with arc-shaped chamfers.

4. The contoured swirler of claim 3, characterised in that the outer venturi (5) is used to arrange the primary combustion stage nozzles, the outer venturi (5) having a cross-sectional shape that is contoured between the circular shape and the swirler profile.

5. The contoured swirler matched to the annular combustion chamber head as claimed in claim 4, characterized in that the wall thickness of the outer, middle venturi tube (5) is greater than the wall thickness of the inner, middle venturi tube (4).

6. The contoured swirler of claim 5, matched to an annular combustion chamber head, characterized in that the high profile (9) of the swirler is concentric to the central axis of the flame tube.

7. The contoured swirler of claim 6, matched to an annular combustion chamber head, characterized in that the bottom profile (10) of the swirler is concentric to the central axis of the flame tube.

8. The shaped swirler of claim 7, matched to the annular combustion chamber head, characterized in that the two sides (6) of the swirler are parallel to the two periodic surfaces of the single-head flame tube, respectively.

9. The shaped swirler of claim 8, characterised in that the junction of the high profile (9) and the bottom profile (10) of the swirler with the two sides (6) is provided with a first rounding (7) and a second rounding (8).

10. Use of a shaped swirler fitted to an annular combustion chamber head, based on any of claims 1 to 9, in the field of aeroengine combustion chamber technology.