A longitudinally corrugated heat shield capable of guiding airflow and providing impingement cooling

Abstract

This invention discloses a longitudinally corrugated heat insulation screen capable of airflow guidance and impact cooling, comprising N heat insulation units; each heat insulation unit includes a first combined plate / ring, a second combined plate / ring, and a connecting plate / ring. The first and second combined plates / rings are provided with through holes for cooling, some of which act as impact holes; the connecting plate / ring is provided with airflow guiding holes. This invention, using the first and second combined plates / rings, effectively prevents the direct impact of high-temperature combustion gases on the windward side of the heat insulation screen, promotes the outflow of cold air from the windward side and the crests of the screen, and allows the cooling air to flow smoothly downstream under the guidance of the airflow channels, forming a cooling air film that protects the wall surface of the longitudinally corrugated heat insulation screen and improves the wall cooling efficiency.

Description

Technical Field

[0001] This invention relates to the field of high-efficiency composite cooling technology, and in particular to a longitudinal corrugated heat shield capable of guiding and impact cooling, for use in the afterburner chamber of an aero-engine or the combustion chamber of a ramjet engine. Background Technology

[0002] With the continuous improvement of the performance of aero-engines and ramjet engines, the average outlet temperature of afterburners / ramjet combustors can reach 1900~2000K, and the outlet temperature of high-performance afterburners / ramjet combustors can even reach 2200K, far exceeding the allowable temperature of current mainstream high-temperature resistant materials. In addition, in order to achieve the purpose of high temperature rise, the inlet temperature of afterburners / ramjet combustors also rises continuously, and more air is used for combustion, which leads to the continuous rise in the temperature of both the combustion gas and the cooling gas in the combustion chamber. The high-temperature components in the afterburner / ramjet combustor face a more severe working environment, thus posing a huge challenge to the cooling of high-temperature components such as heat shields.

[0003] Longitudinal corrugated heat shields, as the mainstream high-temperature components in afterburner / ramjet combustion chambers, are widely used in many engines. However, traditional longitudinal corrugated heat shields often encounter problems such as uneven temperature distribution between peaks and troughs, resulting in large temperature gradients. Specifically, in the trough areas of the heat shield, the cooling gas remains there after exiting the film cooling vents, resulting in lower wall temperatures and better cooling effect. However, on the hot side of the heat shield and in the peak areas, the direct impact of high-temperature combustion gases inhibits the outflow of cooling gas, thus affecting the cooling of the heat shield in these areas, leading to poor high-temperature resistance and short service life. Therefore, adopting efficient composite cooling structures to continuously improve the overall cooling efficiency of the heat shield wall is an important development direction. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the deficiencies mentioned in the background art by providing a longitudinal corrugated heat shield that can perform airflow guidance and impact cooling. Under the same inlet conditions, compared with the traditional longitudinal corrugated heat shield, it can effectively avoid the problem of direct scouring of the hot side windward surface and the crest area by high-temperature gas and the suppression of cooling gas outflow, thereby improving the cooling efficiency of the hot side windward surface and the crest area.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A longitudinally corrugated heat insulation screen capable of guiding and impact cooling includes N heat insulation units, where N is a natural number greater than or equal to 1.

[0007] The insulation unit shown includes a first combined plate, a second combined plate, and a connecting plate;

[0008] The first and second combined plates have the same structure and are wavy. They both include a heat insulation plate and a flow guide plate. The heat insulation plate and the flow guide plate have cross-sections of circular arcs with radii R1 and R2, respectively, where R2 is greater than R1. One end of the heat insulation plate and one end of the flow guide plate are smoothly connected, and the openings of the heat insulation plate and the flow guide plate are opposite.

[0009] The heat insulation plates of the first and second combined plates have opposite openings and their bottom surfaces are on the same plane. The centers of the cross-sections of the heat insulation plates of the first and second combined plates are the same point, and the centers of the cross-sections of the heat insulation plates of the first and second combined plates are the same point, so that the first and second combined plates are partially stacked to form a flow channel.

[0010] The connecting plate is a rectangular plate, which is disposed in the flow channel at the stacking of the first combined plate and the second combined plate. One end is fixedly connected to the first combined plate, and the other end is fixedly connected to the second combined plate.

[0011] The first and second combined plates are provided with a number of through holes for cooling. The through holes on the side of the first and second combined plates near the heat source at the stacking point form an impinging jet to enhance the convective heat transfer on the other side.

[0012] The connecting plate is uniformly provided with a plurality of flow guide holes;

[0013] The N heat insulation units are smoothly connected in sequence, and the heat insulation plate of the second combination plate of the heat insulation unit is smoothly connected to the heat insulation plate of the first combination plate of the adjacent heat insulation unit, and their bottom surfaces are on the same plane.

[0014] As a further optimization of the longitudinal corrugated heat insulation screen capable of guiding and impact cooling according to the present invention, the heat insulation plate and the guide plate have the same thickness, ranging from 0.5 to 2 mm.

[0015] As a further optimization of the longitudinal corrugated heat insulation screen capable of guiding and impact cooling according to the present invention, the diameter of the through holes on the first and second combined plates ranges from 0.5 to 3 mm.

[0016] The present invention also discloses another longitudinal corrugated heat insulation screen capable of guiding and impact cooling, comprising N heat insulation units, where N is a natural number greater than or equal to 1;

[0017] The insulation unit shown includes a first combined ring, a second combined ring, and a connecting ring;

[0018] The first combined ring includes a first heat insulation ring and a first flow guiding ring. The cross-sectional profile of the first heat insulation ring along its axis is two symmetrical arcs with opposite openings and a radius of R1. The cross-sectional profile of the first flow guiding ring along its axis is two symmetrical arcs with opposite openings and a radius of R2. R2 is greater than R1. One end of the first heat insulation ring and one end of the first flow guiding ring are smoothly connected, so that the first heat insulation ring and the first flow guiding ring are coaxial.

[0019] The second combined ring includes a second heat insulation ring and a second flow guide ring. The cross-sectional profile of the second heat insulation ring along its axis is two symmetrical arcs with opposite openings and a radius of R1. The cross-sectional profile of the second flow guide ring along its axis is two symmetrical arcs with opposite openings and a radius of R2. R2 is greater than R1. One end of the second heat insulation ring and one end of the second flow guide ring are smoothly connected, so that the second heat insulation ring and the second flow guide ring are coaxial.

[0020] The first combined ring and the second heat insulation ring are coaxial, and the first flow guide ring extends into the second flow guide ring, so that the first combined ring and the second combined ring are partially stacked to form an annular flow channel;

[0021] The connecting ring is disposed in the flow channel at the stacking of the first combined ring and the second combined ring, with its outer end fixedly connected to the first combined ring and its inner end fixedly connected to the second combined ring.

[0022] The first and second combined rings are provided with a plurality of through holes for cooling, wherein the through holes on the outer side of the stacked portion of the first and second combined rings are used to form an impingement jet to enhance the heat transfer on the inner side.

[0023] The connecting ring is uniformly provided with several flow guide holes;

[0024] The N heat insulation units are smoothly connected in sequence, and the second heat insulation ring of the heat insulation unit and the first heat insulation ring of the adjacent heat insulation unit are smoothly connected and coaxial.

[0025] As a further optimization of this longitudinal corrugated heat shield capable of guiding and impact cooling, the first heat insulation ring, the first flow guiding ring, the second heat insulation ring, and the second flow guiding ring have the same thickness, ranging from 0.5 to 2 mm.

[0026] As a further optimization of the longitudinal corrugated heat shield capable of guiding and impact cooling, the diameter of the through holes on the first and second combined rings ranges from 0.5 to 3 mm.

[0027] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects:

[0028] 1. By utilizing dynamic pressure intake, a portion of the cooling air is passed through the flow channel at the stacked layer of the heat insulation unit in the heat insulation screen, and then through the guide hole, it flows into the hot-side guide channel and flows downstream along the wall to the wave crest area, effectively avoiding the problem of the cooling air outflow being suppressed due to the direct impact of the gas on the windward side.

[0029] 2. Some of the cooling air forms an impinging jet in the through-holes on the heat source side of the stack, which enhances the convective heat transfer on the other side, reduces the wall temperature of the heat shield on the hot side, and provides thermal protection for the heat shield on the hot side.

[0030] 3. Compared with traditional longitudinal corrugated heat insulation screens, this invention can extend the service life of the heat insulation screen and improve its high-temperature resistance. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the first embodiment of the present invention;

[0032] Figure 2 (a) Figure 2 (b) Figure 2 (c) Figure 2 (d) Figure 2 (e) Figure 2 (f) are outline view, sectional view, enlarged partial view, top view, oblique view and right view of the first embodiment of the present invention, respectively;

[0033] Figure 3 This is a schematic diagram of the structure of the second embodiment of the present invention;

[0034] Figure 4 (a) Figure 4 (b) Figure 4 (c) Figure 4 (d) Figure 4 (e) Figure 4 (f) are respectively the outline view, sectional view, enlarged partial view, top view, oblique view and right view of the second embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram illustrating the effects of the present invention. Implementation

[0036] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings:

[0037] This invention can be implemented in many different forms and should not be considered limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully express the scope of the invention to those skilled in the art. In the drawings, components are enlarged for clarity.

[0038] It should be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, and / or parts, these elements, components, and / or parts are not limited by these terms. These terms are merely used to distinguish elements, components, and / or parts from one another. Therefore, the first element, component, and / or part discussed below may be a second element, component, or part without departing from the teachings of this invention.

[0039] like Figure 1 As shown, the present invention discloses a longitudinal corrugated heat insulation screen capable of guiding flow and impact cooling, comprising N heat insulation units, where N is a natural number greater than or equal to 1;

[0040] like Figure 2 (a) Figure 2 (b) Figure 2 (c) Figure 2 (d) Figure 2 (e) Figure 2 As shown in (f), the insulation unit includes a first combined plate, a second combined plate, and a connecting plate;

[0041] The first and second combined plates have the same structure and are wavy. They both include a heat insulation plate and a flow guide plate. The heat insulation plate and the flow guide plate have cross-sections of circular arcs with radii R1 and R2, respectively, where R2 is greater than R1. One end of the heat insulation plate and one end of the flow guide plate are smoothly connected, and the openings of the heat insulation plate and the flow guide plate are opposite.

[0042] The heat insulation plates of the first and second combined plates have opposite openings and their bottom surfaces are on the same plane. The centers of the cross-sections of the heat insulation plates of the first and second combined plates are the same point, and the centers of the cross-sections of the heat insulation plates of the first and second combined plates are the same point, so that the first and second combined plates are partially stacked to form a flow channel.

[0043] The connecting plate is a rectangular plate, which is disposed in the flow channel at the stacking of the first combined plate and the second combined plate. One end is fixedly connected to the first combined plate, and the other end is fixedly connected to the second combined plate.

[0044] The first and second combined plates are provided with a number of through holes for cooling. The through holes on the side of the first and second combined plates near the heat source at the stacking point form an impact jet to enhance heat exchange on the other side.

[0045] The connecting plate is uniformly provided with a plurality of flow guide holes;

[0046] The N heat insulation units are smoothly connected in sequence, and the heat insulation plate of the second combination plate of the heat insulation unit is smoothly connected to the heat insulation plate of the first combination plate of the adjacent heat insulation unit, and their bottom surfaces are on the same plane.

[0047] The heat insulation plate and the flow guide plate have the same thickness, preferably ranging from 0.5 to 2 mm; the diameter of the through holes on the first and second combined plates is preferably ranging from 0.5 to 3 mm.

[0048] Figure 2 In (a), λ is the period length of a single insulation unit, H is the height of a single insulation unit, d is the thickness of the insulation unit structure, R1 is the radius of the arc of the insulation plates of the first and second combined plates, L1 is the chord length of the insulation plates of the first and second combined plates, R2 is the radius of the arc of the guide plate of the second combined plate and the guide plate of the first combined plate, and h d,c h is the height of the guide vane of the second combined plate. d,h The height of the guide plate of the first combined plate.

[0049] Figure 2 In (c), L d,c The height of the cold-side flow channel formed in the guide plate of the second composite plate and the insulation plate of the first composite plate, L d,h The height of the cold-side flow channel formed in the guide plate of the first composite plate and the insulation plate of the second composite plate. l d is the distance from the connecting plate to the axis of the impact hole. f The diameter of the through holes and guide holes arranged on the insulation unit.

[0050] Figure 2 In (d), p represents the spanwise spacing of the through holes arranged on the first and second combined plates, and s represents the flowwise spacing of the through holes arranged on the first and second combined plates.

[0051] like Figure 3 As shown, the present invention also discloses another longitudinal corrugated heat insulation screen capable of guiding flow and impact cooling, comprising N heat insulation units, where N is a natural number greater than or equal to 1.

[0052] like Figure 4 (a) Figure 4 (b) Figure 4 (c) Figure 4 (d) Figure 4 (e) Figure 4 As shown in (f), the insulation unit includes a first combined ring, a second combined ring, and a connecting ring;

[0053] The first combined ring includes a first heat insulation ring and a first flow guiding ring. The cross-sectional profile of the first heat insulation ring along its axis is two symmetrical arcs with opposite openings and a radius of R1. The cross-sectional profile of the first flow guiding ring along its axis is two symmetrical arcs with opposite openings and a radius of R2. R2 is greater than R1. One end of the first heat insulation ring and one end of the first flow guiding ring are smoothly connected, so that the first heat insulation ring and the first flow guiding ring are coaxial.

[0054] The second combined ring includes a second heat insulation ring and a second flow guide ring. The cross-sectional profile of the second heat insulation ring along its axis is two symmetrical arcs with opposite openings and a radius of R1. The cross-sectional profile of the second flow guide ring along its axis is two symmetrical arcs with opposite openings and a radius of R2. R2 is greater than R1. One end of the second heat insulation ring and one end of the second flow guide ring are smoothly connected, so that the second heat insulation ring and the second flow guide ring are coaxial.

[0055] The first combined ring and the second heat insulation ring are coaxial, and the first flow guide ring extends into the second flow guide ring, so that the first combined ring and the second combined ring are partially stacked to form an annular flow channel;

[0056] The connecting ring is disposed in the flow channel at the stacking of the first combined ring and the second combined ring, with its outer end fixedly connected to the first combined ring and its inner end fixedly connected to the second combined ring.

[0057] The first and second combined rings are provided with a plurality of through holes for cooling, wherein the through holes on the outer side of the stacked portion of the first and second combined rings are used to form an impingement jet to enhance the heat transfer on the inner side.

[0058] The connecting ring is uniformly provided with a plurality of flow guide holes;

[0059] The N heat insulation units are smoothly connected in sequence, and the second heat insulation ring of the heat insulation unit and the first heat insulation ring of the adjacent heat insulation unit are smoothly connected and coaxial.

[0060] The first heat insulation ring, the first flow guiding ring, the second heat insulation ring, and the second flow guiding ring have the same thickness, preferably ranging from 0.5 to 2 mm; the diameter of the through holes on the first combined ring and the second combined ring is preferably ranging from 0.5 to 3 mm.

[0061] Figure 4 In (a), λ is the period length of a single thermal insulation unit, H is the height of a single thermal insulation unit, d is the thickness of the thermal insulation unit structure, R1 is the radius of the arc forming the first and second thermal insulation rings, L1 is the chord length of the first and second thermal insulation rings, R2 is the radius of the arc forming the second and first flow guiding rings, and h d,c h is the height of the second guide ring. d,h The height of the first guide ring.

[0062] Figure 4 In (c), L d,c The height of the cold-side flow channel formed in the second flow guide ring and the first heat insulation ring, L d,h The height of the cold-side flow channel formed in the heat insulation ring of the first flow guide ring and the second combined plate. l d is the distance from the connecting ring to the axis of the impact hole. f The aperture of the through holes, guide holes, and impact holes arranged on the insulation unit.

[0063] Figure 4 In (d), p represents the spanwise spacing of the through holes arranged on the insulation unit, and s represents the flowwise spacing of the through holes arranged on the insulation unit.

[0064] like Figure 5 As shown, the working process of this invention is as follows:

[0065] Cooling gas flows out through the through holes, impact holes, and guide holes on the longitudinal wave heat shield wall with guide rings / plates to the hot side of the heat shield. After flowing out of the through holes, part of the cooling gas forms a stagnant vortex at the heat shield of the first combined ring / plate, protecting the wall surface. The first guide ring / plate can effectively prevent the high-temperature combustion gas from directly scouring the heat shield, allowing part of the cooling gas to flow through the cold side guide channel, through the guide holes, and out of the hot side guide channel to form an air film that protects the heat shield area of ​​the downstream second combined ring / plate. In addition, the cooling gas flowing through the impact holes forms an impact jet on the back of the first guide ring / plate, enhancing the heat exchange of the first guide ring / plate.

[0066] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0067] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A longitudinally corrugated heat insulation screen capable of guiding airflow and providing impact cooling, characterized in that, It includes N insulation units, where N is a natural number greater than or equal to 1; The insulation unit shown includes a first combined plate, a second combined plate, and a connecting plate; The first and second combined plates have the same structure and are wavy. They both include a heat insulation plate and a flow guide plate. The heat insulation plate and the flow guide plate have cross-sections of circular arcs with radii R1 and R2, respectively, where R2 is greater than R1. One end of the heat insulation plate and one end of the flow guide plate are smoothly connected, and the openings of the heat insulation plate and the flow guide plate are opposite. The heat insulation plates of the first and second combined plates have opposite openings and their bottom surfaces are on the same plane. The centers of the cross-sections of the heat insulation plates of the first and second combined plates are the same point, and the centers of the cross-sections of the heat insulation plates of the first and second combined plates are the same point, so that the first and second combined plates are partially stacked to form a flow channel. The connecting plate is a rectangular plate, which is disposed in the flow channel at the stacking of the first combined plate and the second combined plate. One end is fixedly connected to the first combined plate, and the other end is fixedly connected to the second combined plate. The first and second combined plates are provided with a number of through holes for cooling. The through holes on the side of the first and second combined plates near the heat source at the stacking point form an impinging jet to enhance the convective heat transfer on the other side. The connecting plate is uniformly provided with a plurality of flow guide holes; The N heat insulation units are smoothly connected in sequence, and the heat insulation plate of the second combination plate of the heat insulation unit is smoothly connected to the heat insulation plate of the first combination plate of the adjacent heat insulation unit, and their bottom surfaces are on the same plane.

2. The longitudinal corrugated heat insulation screen capable of guiding and impact cooling according to claim 1, characterized in that, The heat insulation plate and the flow guide plate have the same thickness, ranging from 0.5 to 2 mm.

3. The longitudinal corrugated heat insulation screen capable of guiding and impact cooling according to claim 1, characterized in that, The diameter of the through holes on the first and second combined plates ranges from 0.5 to 3 mm.

4. A longitudinally corrugated heat insulation screen capable of guiding airflow and providing impact cooling, characterized in that, It includes N insulation units, where N is a natural number greater than or equal to 1; The insulation unit shown includes a first combined ring, a second combined ring, and a connecting ring; The first combined ring includes a first heat insulation ring and a first flow guiding ring. The cross-sectional profile of the first heat insulation ring along its axis is two symmetrical arcs with opposite openings and a radius of R1. The cross-sectional profile of the first flow guiding ring along its axis is two symmetrical arcs with opposite openings and a radius of R2. R2 is greater than R1. One end of the first heat insulation ring and one end of the first flow guiding ring are smoothly connected, so that the first heat insulation ring and the first flow guiding ring are coaxial. The second combined ring includes a second heat insulation ring and a second flow guide ring. The cross-sectional profile of the second heat insulation ring along its axis is two symmetrical arcs with opposite openings and a radius of R1. The cross-sectional profile of the second flow guide ring along its axis is two symmetrical arcs with opposite openings and a radius of R2. R2 is greater than R1. One end of the second heat insulation ring and one end of the second flow guide ring are smoothly connected, so that the second heat insulation ring and the second flow guide ring are coaxial. The first combined ring and the second heat insulation ring are coaxial, and the first flow guide ring extends into the second flow guide ring, so that the first combined ring and the second combined ring are partially stacked to form an annular flow channel; The connecting ring is disposed in the flow channel at the stacking of the first combined ring and the second combined ring, with its outer end fixedly connected to the first combined ring and its inner end fixedly connected to the second combined ring. The first and second combined rings are provided with a plurality of through holes for cooling, wherein the through holes on the outer side of the stacked portion of the first and second combined rings are used to form an impingement jet to enhance the internal heat transfer. The connecting ring is uniformly provided with a plurality of flow guide holes; The N heat insulation units are smoothly connected in sequence, and the second heat insulation ring of the heat insulation unit and the first heat insulation ring of the adjacent heat insulation unit are smoothly connected and coaxial.

5. The longitudinal corrugated heat insulation screen capable of guiding and impact cooling according to claim 4, characterized in that, The first heat insulation ring, the first flow guide ring, the second heat insulation ring, and the second flow guide ring have the same thickness, ranging from 0.5 to 2 mm.

6. The longitudinal corrugated heat insulation screen capable of guiding and impact cooling according to claim 5, characterized in that, The diameter of the through holes on the first and second combined rings ranges from 0.5 to 3 mm.

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