Cooling structure for expansion section of thrust vectoring nozzle

Abstract

The invention discloses a thrust vectoring nozzle expansion section cooling structure, and relates to the technical field of thrust vectoring nozzles, the thrust vectoring nozzle expansion section cooling structure comprises a supporting seat, a movable element, a first heat screen and a second heat screen, the lower end of the supporting seat is installed on an expansion adjusting sheet, the movable element is movably installed at the upper end of the supporting seat, and the first heat screen and the second heat screen are respectively located at two sides of the movable element; a cold air cavity is formed below the first heat insulation screen and the second heat insulation screen, a fuel gas cavity is formed above the first heat insulation screen and the second heat insulation screen, the first end of the movable element is located at the upper end of the first heat insulation screen, and the second end of the movable element is located at the lower end of the second heat insulation screen. And when the pressure intensity in the cold air cavity is smaller than that in the gas cavity, the movable element rotates to enable the cold air cavity not to communicate with the gas cavity. Normal outflow and flowing of cold air in the design state of the expansion section can be achieved, and gas backflow in the local non-design state of the expansion section is restrained.

Description

Technical Field

[0001] The invention relates to the technical field of vector nozzles, and in particular to a cooling structure of an expansion section of a vector nozzle. Background Art

[0002] Domestic third-generation engines mostly use axisymmetric convergent-divergent nozzles, which basically use jet cooling to cool the convergent adjustment plate, and no cooling is used for the expansion adjustment plate. The adjustment plate of the vector nozzle is closer to the core flow, and the heat load is more severe. At the same time, in order to reduce infrared radiation and improve stealth performance, a more efficient open-hole cooling method must be adopted. Vector nozzle cooling is a new key technology for vector nozzles that develops synchronously with the vector nozzle, so it is urgent to design a reasonable and reliable cooling structure.

[0003] At present, the mainstream of the expansion section of the vector nozzle has reached supersonic speed. Due to the existence of the nozzle shock wave system, the mainstream pressure change of the expansion section is complicated, while the cooling channel flows at subsonic speed and the flow is relatively smooth, so that the nozzle cold air pressure environment is equivalent to the outer culvert inlet pressure. Under the combined effect of the two, the internal and external pressure difference of the expansion section cooling structure changes dramatically. At the same time, because the expansion section of the vector nozzle needs to realize both the contraction and expansion function and the vector function, the usage mode is changeable, which makes the mainstream flow and pressure changeable, and also causes the internal and external pressure difference of the expansion section cooling structure to change dramatically. Under the influence of the above factors, the internal and external pressure difference of the cooling structure of the nozzle expansion section is very likely to produce backflow, which increases the heat load of the nozzle. In severe cases, it may cause problems such as ablation of the nozzle expansion section. Summary of the invention

[0004] The purpose of the present invention is to provide a cooling structure for the expansion section of a vector nozzle to solve the problems existing in the above-mentioned prior art, to achieve normal outflow of cold air under the design state of the expansion section, and to suppress the backflow of gas under the local non-design state of the expansion section.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a cooling structure for the expansion section of a vector nozzle, comprising a support seat, an expansion adjustment plate, a movable element, a first heat insulation screen and a second heat insulation screen, wherein the lower end of the support seat is mounted on the expansion adjustment plate, the movable element is movably mounted on the upper end of the support seat, and the first heat insulation screen and the second heat insulation screen are respectively located on both sides of the movable element, the lower parts of the first heat insulation screen and the second heat insulation screen are cold air chambers, the upper parts of the first heat insulation screen and the second heat insulation screen are gas chambers, the first end of the movable element is located at the upper end of the first heat insulation screen, and the second end of the movable element is located at the lower end of the second heat insulation screen, when the pressure in the cold air chamber is greater than the pressure in the gas chamber, the movable element can be rotated to connect the cold air chamber with the gas chamber, and when the pressure in the cold air chamber is less than the pressure in the gas chamber, the movable element can be rotated to disconnect the cold air chamber from the gas chamber.

[0007] Preferably, there are two support seats, which are respectively arranged close to two sides of the movable element and are both movably connected to the movable element.

[0008] Preferably, the movable element includes a pressure difference regulating plate and two rotating elements, the lower end surface of the pressure difference regulating plate is integrally formed with two connecting parts, and the two connecting parts are both arranged close to the first heat insulation screen, the connecting parts, the rotating elements and the support seat correspond to each other one by one, and the connecting part is rotatably installed on the upper end of the support seat through the rotating elements, when the pressure in the cold air chamber is greater than the pressure in the gas chamber, the pressure difference regulating plate can be rotated until the two ends of the pressure difference regulating plate are respectively separated from the first heat insulation screen and the second heat insulation screen, and when the pressure in the cold air chamber is less than the pressure in the gas chamber, the pressure difference regulating plate can be rotated until the two ends of the pressure difference regulating plate are respectively in contact with the first heat insulation screen and the second heat insulation screen.

[0009] Preferably, the movable element also includes two stop plates, which correspond one to one with the support seat, and the first end of the stop plate is fixed to one end of the pressure difference adjusting plate close to the first heat insulation screen, and the second end of the stop plate extends in a direction close to the lower end of the support seat, and the stop plate is perpendicular to the pressure difference adjusting plate. When the pressure difference adjusting plate is rotated to connect the cold air cavity with the gas cavity, the second end of the stop plate can abut against the side wall of the support seat.

[0010] Preferably, the rotating element includes a bolt and a nut, and the bolt passes through the connecting portion and the upper end of the supporting seat and is connected to the nut.

[0011] Compared with the prior art, the present invention has achieved the following technical effects:

[0012] The cooling structure of the expansion section of a vector nozzle provided by the present invention has a lower end of a support seat mounted on an expansion adjustment plate, a movable element movably mounted on an upper end of the support seat, and a first heat insulation screen and a second heat insulation screen are respectively located on both sides of the movable element, a cold air cavity is located below the first heat insulation screen and the second heat insulation screen is located above a gas cavity, a first end of the movable element is located at an upper end of the first heat insulation screen, and a second end of the movable element is located at a lower end of the second heat insulation screen, and then different actions of the movable element are realized by changing the pressure difference on both sides of the first heat insulation screen and the second heat insulation screen to meet different usage needs, and when the pressure in the cold air cavity is greater than the pressure in the gas cavity, the movable element can be rotated under the action of the cold air flow to make the movable element The two ends are separated from the first heat insulation screen and the second heat insulation screen respectively, so that the cold air cavity is connected with the gas cavity. At this time, the cold air flow flows from the two ends of the active element to the gas cavity, so as to cool the active element, the first heat insulation screen and the second heat insulation screen. When the pressure in the cold air cavity is lower than the pressure in the gas cavity, the active element can rotate under the action of the gas flow so that the two ends of the active element contact the first heat insulation screen and the second heat insulation screen respectively, so that the cold air cavity and the gas cavity are disconnected. At this time, the gas flow cannot flow to the cold air cavity, so as to avoid the backflow of gas in the negative pressure difference environment of the expansion section. Then, under the premise of cooling the first heat insulation screen and the second heat insulation screen of the expansion section by the cold air outflow in the positive pressure difference environment, the problem of gas backflow in the negative pressure difference environment is solved, and the structure is simple and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 It is a schematic diagram of the working state of the cooling structure of the expansion section of the vector nozzle in the present invention;

[0015] Figure 2 It is a structural schematic diagram of the cooling structure of the expansion section of the vector nozzle in the present invention;

[0016] Figure 3 A cross-sectional view of the cooling structure of the expansion section of the vector nozzle in the present invention;

[0017] In the figure: 1-first heat insulation screen, 2-pressure difference adjustment plate, 3-second heat insulation screen, 4-support seat, 5-expansion adjustment plate, 6-bolt, 7-nut, 8-gas cavity, 9-cold air cavity, 10-first gap, 11-second gap, 12-stop plate. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] The purpose of the present invention is to provide a cooling structure for the expansion section of a vector nozzle to solve the problems existing in the prior art, to achieve normal outflow of cold air in the design state of the expansion section, and to suppress the backflow of gas in the local non-design state of the expansion section.

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] like Figure 1-Figure 3 As shown, the present embodiment provides a cooling structure of the expansion section of a vector nozzle, comprising a support seat 4, an expansion adjustment sheet 5, a movable element, a first heat insulation screen 1 and a second heat insulation screen 3, the lower end of the support seat 4 is mounted on the expansion adjustment sheet 5, the movable element is movably mounted on the upper end of the support seat 4, and the first heat insulation screen 1 and the second heat insulation screen 3 are respectively located on both sides of the movable element, the lower part of the first heat insulation screen 1 and the second heat insulation screen 3 is a cold air cavity 9, the upper part of the first heat insulation screen 1 and the second heat insulation screen 3 is a gas cavity 8, the first end of the movable element is located at the upper end of the first heat insulation screen 1, and the second end of the movable element is located at the lower end of the second heat insulation screen 3, and then through the pressure difference change on both sides of the first heat insulation screen 1 and the second heat insulation screen 3, different actions of the movable element are realized to meet different usage needs, when the pressure in the cold air cavity 9 is greater than the pressure in the gas cavity 8, the movable element Under the action of the cold air flow, it can rotate until the two ends of the movable element are respectively separated from the first heat insulation screen 1 and the second heat insulation screen 3, so that the cold air cavity 9 is connected with the gas cavity 8. At this time, the cold air flow flows from the two ends of the movable element to the gas cavity 8, so as to realize the cooling of the movable element, the first heat insulation screen 1 and the second heat insulation screen 3; when the pressure in the cold air cavity 9 is lower than the pressure in the gas cavity 8, the movable element can rotate under the action of the gas flow until the two ends of the movable element are respectively in contact with the first heat insulation screen 1 and the second heat insulation screen 3, so that the cold air cavity 9 is not connected with the gas cavity 8. At this time, the gas flow cannot flow to the cold air cavity 9, so as to avoid the gas backflow in the negative pressure difference environment of the expansion section, and then under the premise of realizing the cooling of the first heat insulation screen 1 and the second heat insulation screen 3 of the expansion section by the cold air outflow in the positive pressure difference environment, the gas backflow problem in the negative pressure difference environment is solved, and the structure is simple and easy to realize.

[0022] Specifically, there are two support seats 4, which are respectively arranged close to the two sides of the movable element and are both movably connected to the movable element to improve the rotation stability of the movable element.

[0023] The movable element includes a pressure differential regulating plate 2 and two rotating elements. The lower end surface of the pressure differential regulating plate 2 is integrally formed with two connecting parts, and the two connecting parts are arranged close to the first heat insulation screen 1. The connecting parts, the rotating elements and the support seat 4 correspond to each other one by one. The connecting part is rotatably installed on the upper end of the support seat 4 through the rotating element. When the pressure in the cold air cavity 9 is greater than the pressure in the combustion gas cavity 8 (that is, when Pc>Ph), the expansion section is in a positive pressure differential state, and the pressure differential regulating plate 2 can be rotated until the two ends of the pressure differential regulating plate 2 are respectively separated from the first heat insulation screen 1 and the second heat insulation screen 3, and at this time, a first gap 10 is formed between the upper surface of the first end of the pressure differential regulating plate 2 and the lower surface of the first heat insulation screen 1, and the lower surface of the second end of the pressure differential regulating plate 2 and the second heat insulation screen 3, the first gap 10 and the second gap 11 are both in the maximum gap state, so that the cold air flow in the cold air cavity 9 can flow into the gas cavity 8 through the first gap 10 and the second gap 11, and cool the pressure difference regulating plate 2, the first heat insulation screen 1 and the second heat insulation screen 3. When the pressure in the cold air cavity 9 is lower than the pressure in the gas cavity 8 (that is, when Pc<Ph), the expansion section is in a negative pressure difference state, and the pressure difference regulating plate 2 can be rotated until the two ends of the pressure difference regulating plate 2 contact the first heat insulation screen 1 and the second heat insulation screen 3 respectively. At this time, the first gap 10 and the second gap 11 do not exist, so that the gas flow in the gas cavity 8 is prevented from entering the cold air cavity 9, and the gas backflow under the negative pressure difference environment of the expansion section is prevented.

[0024] The movable element also includes two stop plates 12, which correspond one-to-one to the support seat 4. The first end of the stop plate 12 is fixed to one end of the pressure difference adjusting plate 2 close to the first heat insulation screen 1, and the second end of the stop plate 12 extends toward the lower end of the support seat 4. The stop plate 12 is perpendicular to the pressure difference adjusting plate 2. When the pressure difference adjusting plate 2 is rotated to connect the cold air cavity 9 with the gas cavity 8, the second end of the stop plate 12 can abut against the side wall of the support seat 4, so that the pressure difference adjusting plate 2 can no longer rotate, thereby limiting the rotation of the pressure difference adjusting plate 2.

[0025] The rotating element includes a bolt 6 and a nut 7. The bolt 6 passes through the connecting portion and the upper end of the support seat 4 and is connected to the nut 7. While achieving the connection between the pressure difference regulating plate 2 and the support seat 4, it also ensures that the pressure difference regulating plate 2 can rotate relative to the support seat 4.

[0026] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A cooling structure for the expansion section of a vector nozzle, Features: It includes a support seat, an expansion adjustment plate, a movable element, a first heat insulation screen and a second heat insulation screen, the lower end of the support seat is installed on the expansion adjustment plate, the movable element is movably installed on the upper end of the support seat, and the first heat insulation screen and the second heat insulation screen are respectively located on both sides of the movable element, the lower part of the first heat insulation screen and the second heat insulation screen is a cold air cavity, the upper part of the first heat insulation screen and the second heat insulation screen is a gas cavity, the first end of the movable element is located at the upper end of the first heat insulation screen, and the second end of the movable element is located at the lower end of the second heat insulation screen, when the pressure in the cold air cavity is greater than the pressure in the gas cavity, the movable element can be rotated to connect the cold air cavity with the gas cavity, and when the pressure in the cold air cavity is less than the pressure in the gas cavity, the movable element can be rotated to disconnect the cold air cavity with the gas cavity.

2. The cooling structure of the expansion section of the vector nozzle according to claim 1, Features: There are two support seats, which are respectively arranged close to two sides of the movable element and are both movably connected to the movable element.

3. The cooling structure of the expansion section of the vector nozzle according to claim 2, Features: The movable element includes a pressure difference regulating plate and two rotating elements. The lower end surface of the pressure difference regulating plate is integrally formed with two connecting parts, and the two connecting parts are both arranged close to the first heat insulation screen. The connecting parts, the rotating elements and the support seat correspond to each other one by one. The connecting part is rotatably installed on the upper end of the support seat through the rotating elements. When the pressure in the cold air cavity is greater than the pressure in the gas cavity, the pressure difference regulating plate can be rotated until the two ends of the pressure difference regulating plate are respectively separated from the first heat insulation screen and the second heat insulation screen. When the pressure in the cold air cavity is less than the pressure in the gas cavity, the pressure difference regulating plate can be rotated until the two ends of the pressure difference regulating plate are respectively in contact with the first heat insulation screen and the second heat insulation screen.

4. The cooling structure of the expansion section of the vector nozzle according to claim 3, Features: The movable element also includes two stop plates, which correspond to the support seats one by one. The first end of the stop plate is fixed to one end of the pressure difference adjusting plate close to the first heat insulation screen, and the second end of the stop plate extends toward the lower end of the support seat. The stop plate is perpendicular to the pressure difference adjusting plate. When the pressure difference adjusting plate is rotated to connect the cold air cavity with the gas cavity, the second end of the stop plate can abut against the side wall of the support seat.

5. The cooling structure of the expansion section of the vector nozzle according to claim 3, Features: The rotating element includes a bolt and a nut, wherein the bolt passes through the connecting portion and the upper end of the supporting seat and is connected to the nut.

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