A thermal protection structure for an engine combustion chamber housing and a preparation method thereof

Abstract

The present invention discloses a thermal protection structure for an engine combustion chamber housing and a preparation method thereof. The thermal protection structure of the engine combustion chamber housing includes a heat insulation layer, a plurality of rubber gaskets, and a heat protection layer. The heat insulation layer is laid and fixed between the front end frame and the rear end frame. Rubber gaskets are respectively arranged on the outer end faces of the combustion chamber in the front end frame, the rear end frame, and the first gap. Reinforcing ribs are respectively fixedly arranged on the rubber gaskets. The heat protection layer is arranged on the heat insulation layer and the plurality of reinforcing ribs. A stable multi-layer structure is effectively formed between the front end frame, the rear end frame, and the outer end face of the combustion chamber through the thermal protection structure. The heat insulation layer and the heat protection layer maintain the structural integrity through the rubber gaskets and the reinforcing ribs, and the structure is stable and does not deform. When the combustion chamber expands, the extended setting at one end of the heat protection layer effectively plays a complementary role with the expansion amount of the combustion chamber, maintaining the overall reliability. Under the working conditions of long-term high-speed operation, a more stable thermal protection effect is improved.

Description

Technical Field

[0001] This application relates to the technical field of aerospace engines, and particularly relates to a thermal protection structure for an engine combustion chamber housing and a preparation method thereof. Background Art

[0002] With the development of the aerospace industry, the requirements for flight duration are getting longer and the requirements for flight speed are getting higher. The time that the original engine thrust system stays on the flight product is also getting longer, and thus the demand for thermal protection on the outer surface of the engine is getting higher. The original heat-resistant spraying materials and spraying methods can no longer meet the subsequent development needs due to their limited heat protection ability and fragile structure. Summary of the Invention

[0003] Aiming at the defects existing in the prior art, this application provides a thermal protection structure for an engine combustion chamber housing and a preparation method thereof to solve the problems of bottleneck in heat protection ability and fragile structure in the existing thermal protection system.

[0004] The above object of the present invention is mainly achieved by the following technical solutions:

[0005] A thermal protection structure for an engine combustion chamber housing, comprising:

[0006] A heat insulation layer, which is used to be attached to the outer end face of the combustion chamber and fixed between the front frame and the rear frame. A first gap is provided in the middle of the heat insulation layer;

[0007] A plurality of rubber gaskets, which are respectively arranged on the outer end face of the combustion chamber in the front frame, the rear frame and the first gap. Reinforcing ribs are respectively fixed on the rubber gaskets, and the top surfaces of the reinforcing ribs are coplanar with the top surface of the heat insulation layer;

[0008] A heat protection layer, which is laid on the heat insulation layer and a plurality of the reinforcing ribs, and one end of the heat protection layer extends out of the side of the rear frame away from the front frame.

[0009] Another object of this application is to provide a preparation method for the thermal protection structure of the engine combustion chamber housing as described above, comprising the following steps:

[0010] Determine the forming positions of the heat insulation layer and the reinforcing ribs;

[0011] Take the heat insulation layer and lay it along the forming positions on the die surface and bond it to the outer end face of the combustion chamber;

[0012] Take the rubber gaskets and respectively arrange them on the front frame, the rear frame and the outer end face of the combustion chamber according to the forming positions;

[0013] Take the first prepreg tape and lay or wind it layer by layer on the rubber gasket to form a reinforcing rib;

[0014] Cover a separator film and a vacuum film on the reinforcing rib and the heat insulation layer in sequence, evacuate the air until it is shaped, and then remove the vacuum film and the separator film;

[0015] Take the second prepreg tape and lay it layer by layer on the reinforcing rib and the heat insulation layer to form a heat protection layer. Cover a separator film, a rubber absorption paper, and a vacuum film outside the heat protection layer in sequence, heat and cure it, and then remove the separator film, the rubber absorption paper, and the vacuum film to obtain the thermal protection structure.

[0016] Further, the rubber gasket is pre-punched before bonding.

[0017] Further, the punching rate of the rubber gasket is 25% - 45%.

[0018] Further, the surface of the rubber gasket is bonded with a rubber-based adhesive.

[0019] Further, the heat insulation layer is made by cutting a prepreg of an aerogel material.

[0020] Further, the first prepreg tape is made by cutting a prepreg of a microsphere heat insulation material.

[0021] Further, the second prepreg tape is made by cutting a prepreg of a ceramizable material.

[0022] Further, remove the flash and trim the shape of the obtained thermal protection structure.

[0023] Further, the laying or winding direction of the heat insulation layer is consistent with the axis direction of the mold.

[0024] Compared with the prior art, the advantages of the present invention are as follows:

[0025] In the present invention, a heat insulation layer is attached to the outer end face of the combustion chamber and laid and fixed between the front end frame and the rear end frame. A first gap is provided in the middle of the heat insulation layer. Rubber gaskets are respectively arranged on the outer end face of the combustion chamber within the front end frame, the rear end frame and the first gap, and reinforcing ribs are respectively fixed on the rubber gaskets, such that the top surfaces of the reinforcing ribs are coplanar with the top surface of the heat insulation layer. A heat protection layer is arranged on the heat insulation layer and the plurality of reinforcing ribs, and one end of the heat protection layer extends out of the side of the rear end frame away from the front end frame. A stable multi-layer structure is effectively formed between the front end frame, the rear end frame and the outer end face of the combustion chamber through the heat protection structure. When the engine is in use, the heat insulation layer and the heat protection layer maintain the structural integrity through the rubber gaskets and the reinforcing ribs, and the structure is stable and does not deform. When the combustion chamber expands, the extended setting of one end of the heat protection layer effectively plays a complementary role with the expansion amount of the combustion chamber, maintaining the overall reliability and providing a more stable heat protection effect under the working conditions of long-term high-speed operation. Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 It is the first partial cross-sectional view of the heat protection structure provided by the embodiment of the present application;

[0028] Figure 2 It is the second partial cross-sectional view of the heat protection structure provided by the embodiment of the present application;

[0029] Figure 3 It is the flow chart of the preparation method of the heat protection structure provided by the embodiment of the present application;

[0030] In the figures: 1, heat insulation layer; 2, rubber gasket; 3, reinforcing rib; 4, heat protection layer; 5, front end frame; 6, rear end frame; 7, combustion chamber. Detailed Embodiments

[0031] The following further elaborates the present invention in conjunction with the drawings and specific embodiments. It should be noted here that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation to the present invention. The specific structural and functional details disclosed herein are only used to describe the exemplary embodiments of the present invention. However, the present invention can be embodied in many alternative forms and should not be construed as limited to the embodiments described herein.

[0032] As Figure 1-2As shown in the figure, a thermal protection structure for the housing of an engine combustion chamber 7 includes a heat insulation layer 1, a plurality of rubber gaskets 2, and a heat protection layer 4, where:

[0033] The heat insulation layer 1 is used to be attached to the outer end face of the combustion chamber 7 and is used to be fixed between the front frame 5 and the rear frame 6. A first gap is provided in the middle of the heat insulation layer 1. There is a stable fixed connection relationship between the front frame 5, the rear frame 6, and the engine combustion chamber 7. The heat insulation layer 1 is attached to the outer end face of the combustion chamber 7. When the heat insulation layer 1 is arranged between the front frame 5 and the rear frame 6, the heat insulation layer 1 can also be stably connected between the front frame 5 and the rear frame 6 to maintain the continuous heat insulation effect on the outer end face of the combustion chamber 7 between the front frame 5 and the rear frame 6. The arrangement of the first gap can be correspondingly arranged according to the easily deformable direction of the combustion chamber 7, and the first gap can also be arranged in a staggered manner according to the specifications of the outer end face of the combustion chamber 7. No further restrictions are imposed here.

[0034] A plurality of the rubber gaskets 2 are used to be respectively arranged on the outer end faces of the combustion chamber 7 in the front frame 5, the rear frame 6, and the first gap. Reinforcing ribs 3 are respectively fixed on the rubber gaskets 2, and the top surfaces of the reinforcing ribs 3 are coplanar with the top surface of the heat insulation layer 1. Rubber gaskets 2 are respectively arranged on the front frame 5 and the rear frame 6, and according to the arrangement of the first gap, rubber gaskets 2 are also arranged on the outer end face of the combustion chamber 7. The reinforcing ribs 3 are correspondingly arranged with the rubber gaskets 2 as the arrangement positions, and the top surfaces of the reinforcing ribs 3 are controlled to be coplanar with the top surface of the heat insulation layer 1, so that the heat insulation layer 1, the rubber gaskets 2, and the reinforcing ribs 3 together provide a flat installation working surface.

[0035] There are certain matching problems for flight products in a thermal environment. The compressive strength formed at the position of the reinforcing ribs 3 is low, and there is a certain risk of deformation in the structure of the reinforcing ribs 3. Therefore, rubber gaskets 2 with a certain thickness are added on the side of the reinforcing ribs 3 close to the front frame 5, the rear frame 6, and the outer end face of the combustion chamber 7, and the rubber gaskets 2 are used as a coordinated strain layer to meet the thermal matching problem and further improve the reliability.

[0036] The heat protection layer 4 is laid on the heat insulation layer 1 and a plurality of the reinforcing ribs 3. The top surfaces of the reinforcing ribs 3 and the heat insulation layer 1 are on the same working surface. The heat protection layer 4 can be stably and completely laid, and one end of the heat protection layer 4 extends out of the side of the rear frame 6 far from the front frame 5. That is to say, in the direction from the front frame 5 to the rear frame 6, the length of the heat protection layer 4 is greater than the sum of the lengths of the heat insulation layer 1, the front frame 5, and the rear frame 6. Furthermore, the length coverage of the expansion amount of the combustion chamber 7 is formed on the side farthest from the combustion chamber 7 through the heat protection layer 4 to maintain a more stable thermal protection effect.

[0037] The working principle of this embodiment is as follows: By attaching a heat insulation layer 1 to the outer end face of the combustion chamber 7 and laying and fixing this heat insulation layer 1 between the front end frame 5 and the rear end frame 6, a first gap is provided in the middle of the heat insulation layer 1. Rubber gaskets 2 are respectively arranged on the outer end faces of the front end frame 5, the rear end frame 6 and the combustion chamber 7 within the first gap, and reinforcing ribs 3 are fixedly arranged on the rubber gaskets 2 respectively, such that the top surfaces of the reinforcing ribs 3 are coplanar with the top surface of the heat insulation layer 1. A heat protection layer 4 is arranged on the heat insulation layer 1 and multiple reinforcing ribs 3, and one end of the heat protection layer 4 extends out of the side of the rear end frame 6 away from the front end frame 5. Through the heat protection structure, a stable multi-layer structure is effectively formed between the front end frame 5, the rear end frame 6 and the outer end face of the combustion chamber 7. When the engine is in use, the heat insulation layer 1 and the heat protection layer 4 maintain the structural integrity through the rubber gaskets 2 and the reinforcing ribs 3, and the structure is stable and does not deform. Moreover, when the combustion chamber 7 expands, the extended setting of one end of the heat protection layer 4 effectively plays a complementary role with the expansion amount of the combustion chamber 7, maintaining the overall reliability and providing a more stable heat protection effect under the working conditions of long-term high-speed operation.

[0038] As Figure 1-3 shown, for the preparation method of the heat protection structure of the above-mentioned engine combustion chamber 7 housing in this application, it includes the following steps:

[0039] Determine the forming positions of the heat insulation layer 1 and the reinforcing ribs 3;

[0040] Take the heat insulation layer and lay it along the mold surface according to the forming positions, and bond it to the outer end face of the combustion chamber 7;

[0041] Take the rubber gaskets 2 and respectively arrange them on the outer end faces of the front end frame 5, the rear end frame 6 and the combustion chamber 7 according to the forming positions;

[0042] Take the first prepreg tape and layer by layer lay or wind it on the rubber gaskets 2 to form the reinforcing ribs 3;

[0043] Coat a separator film and a vacuum film on the reinforcing ribs 3 and the heat insulation layer 1 in sequence, evacuate until it is shaped and then remove the vacuum film and the separator film;

[0044] Take the second prepreg tape and layer by layer lay it on the reinforcing ribs 3 and the heat insulation layer 1 to form the heat protection layer 4. Coat a separator film, a resin absorbent paper and a vacuum film on the outside of the heat protection layer 4 in sequence, heat and cure it and then remove the separator film, the resin absorbent paper and the vacuum film to obtain the heat protection structure.

[0045] During the process of the above steps, when determining the forming positions of the heat insulation layer 1 and the reinforcing ribs 3, according to the specifications of the combustion chamber 7, the forming positions of the reinforcing ribs 3 and the layout range of the heat insulation layer 1 can be determined on the outer end face of the combustion chamber 7.

[0046] A mold with the same specifications as the outer end face of the combustion chamber 7 can be set and used for the laying and forming of the heat insulation layer. During the laying or winding process of the heat insulation layer, the thickness of multiple layers of the heat insulation layer can be intermittently measured. After the thickness meets the requirements, a water-absorbing cloth is used for winding, and a drying furnace can be used for the drying operation.

[0047] To maintain the tight adhesion of the heat insulation layer 1, a phenolic pre-impregnated cloth is used as an adhesive on the surface of the heat insulation layer 1. The base material of the phenolic pre-impregnated cloth can be a phenolic pre-impregnated cloth of alkali-free glass fiber impregnated cloth or a phenolic pre-impregnated cloth of high-silica glass fiber.

[0048] When taking the first pre-impregnated cloth tape for laying or winding operations, the top surface of the first pre-impregnated cloth tape for laying or winding is basically flush with the top of the heat insulation layer 1 to obtain a more uniform laying working surface for the heat protection layer 4.

[0049] Furthermore, the rubber gasket 2 is pre-punched before bonding. Considering the deformable space required for the rib 3 during compression and the difference in heat insulation effect between the rib 3 part and the heat insulation layer 1, some voids are prefabricated in the rubber gasket 2 in advance to provide the deformable space required for the rib 3 during compression and improve the overall structural stability.

[0050] Furthermore, the punching rate on the rubber gasket 2 is 25% - 45% to maintain the supporting capacity of the rubber gasket 2 and provide the necessary deformation space, improving the overall dynamic stability.

[0051] Furthermore, the surface of the rubber gasket 2 is bonded with a rubber-based adhesive, such as an adhesive with the model number GD-414 or XY-401, to maintain a stable connection relationship of the rubber gasket 2.

[0052] Furthermore, the heat insulation layer is cut from a pre-impregnated cloth of aerogel material and arranged in at least one of plain weave, twill weave, satin weave, and grid for the heat insulation layer.

[0053] Due to the low density of aerogel, a heat transfer barrier effect can be obtained. The strength of the low-density aerogel is low. To meet the anti-deformation ability of the material and ensure the reliability and stability of the overall thermal protection structure, ribs 3 with higher strength and arranged in a staggered manner are added in the heat insulation layer 1 for support.

[0054] Furthermore, the first pre-impregnated cloth tape is cut from a pre-impregnated cloth of microsphere heat insulation material and arranged in at least one of plain weave, twill weave, satin weave, and grid for the first pre-impregnated cloth tape.

[0055] Further, the second pre-impregnated cloth tape is cut from a pre-impregnated cloth made of an ablation-resistant ceramizable material, and the heat insulation layer is arranged in at least two of plain weave, twill weave, satin weave, and grid pattern.

[0056] Further, the obtained thermal protection structure is trimmed to remove burrs and shape, so as to maintain the overall consistency of the thermal protection structure.

[0057] Further, the laying or winding direction of the heat insulation layer is consistent with the axis direction of the mold.

[0058] In specific implementation, the preparation method of the thermal protection structure of the engine combustion chamber 7 housing is operated as follows:

[0059] Clean the mold surface with alcohol, determine the forming positions of the heat insulation layer 1 and the reinforcing rib 3 on the outer end surface of the combustion chamber 7, and draw lines;

[0060] Cut the heat insulation layer from a pre-impregnated cloth of aerogel material, lay the heat insulation layer layer by layer along the mold surface in twill weave, then wrap it with a water-absorbing cloth and tighten it, place it in an oven and raise the temperature step by step to 190° for curing, then cool it down to 40° and remove the water-absorbing cloth to obtain the heat insulation layer 1, and then use a phenolic pre-impregnated cloth of alkali-free glass fiber impregnated cloth as an adhesive to bond the heat insulation layer 1 to the outer end surface of the combustion chamber 7 according to the lines of the forming positions;

[0061] Take the rubber gasket 2 and perform pre-punching treatment with a punching rate of 30%, and use an adhesive of model XY-401 to set it on the front end frame 5, the rear end frame 6 and the outer end surface of the combustion chamber 7 respectively according to the forming positions;

[0062] Cut the pre-impregnated cloth of microsphere heat insulation material to obtain the first pre-impregnated cloth tape, and lay it layer by layer on the rubber gasket 2 in plain weave to form the reinforcing rib 3, and increase the thickness of the reinforcing rib 3 through the holes, so that the top surface of the reinforcing rib 3 is coplanar with the top surface of the heat insulation layer 1;

[0063] Wrap the separator film and the vacuum film on the reinforcing rib 3 and the heat insulation layer 1 in sequence, evacuate until it is shaped, and then remove the vacuum film and the separator film;

[0064] Cut the pre-impregnated cloth of an ablation-resistant ceramizable material to obtain the second pre-impregnated cloth tape, and lay it layer by layer on the reinforcing rib 3 and the heat insulation layer 1 in a grid pattern to form the heat protection layer 4. During the laying process, keep the length of the heat protection layer 4 greater than the sum of the lengths of the heat insulation layer 1, the front end frame 5 and the rear end frame 6, that is, keep one edge of the heat protection layer 4 extending beyond the outside of the rear end frame 6, and control the thickness of the heat protection layer 4 to meet the design requirements. Wrap the separator film, the absorbent paper and the vacuum film on the heat protection layer 4 in sequence, place it in an oven and raise the temperature step by step to 200° for curing, then cool it down to 40°, and remove the separator film, the absorbent paper and the vacuum film to obtain the thermal protection structure.

[0065] Polish and clean the overflow glue and flash on the outer surface of the thermal protection structure.

[0066] It should be understood that the terms first, second, etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance. Although the terms first, second, etc. may be used herein to describe various units, these units should not be limited by these terms. These terms are only used to distinguish one unit from another. For example, the first unit may be referred to as the second unit, and similarly, the second unit may be referred to as the first unit, without departing from the scope of the exemplary embodiments of the present invention.

[0067] It should be understood that the term "and / or" herein is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" herein describes another association relationship of associated objects, indicating that two relationships may exist. For example, A / and B may represent: A exists alone, and A and B exist alone. In addition, the character " / " herein generally indicates that the associated objects before and after are in an "or" relationship.

[0068] It should be understood that in the description of the present invention, the orientation or positional relationship indicated by the terms "upper", "vertical", "inner", "outer", etc. is the orientation or positional relationship in which the disclosed product is usually placed during use, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0069] In the description of the present invention, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "install", "connect" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention may be understood according to specific circumstances.

[0070] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the exemplary embodiments of the present invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the terms "comprises", "comprising", "includes" and / or "including", when used herein, specify the presence of the stated features, integers, steps, operations, units and / or components, and do not preclude the presence or addition of one or more other features, numbers, steps, operations, units, components and / or combinations thereof.

[0071] Specific details are provided in the following description to facilitate a thorough understanding of the exemplary embodiments. However, those of ordinary skill in the art should understand that the exemplary embodiments may be implemented without these specific details. In other instances, well-known processes, structures and techniques have not been shown in unnecessary detail to avoid obscuring the exemplary embodiments.

[0072] The above are only specific embodiments of the present application, which enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. A thermal protection structure for an engine combustion chamber housing, characterized in that It includes: A heat insulation layer which is used to be pasted on the outer end face of the combustion chamber and fixed between the front end frame and the rear end frame, and a first gap is provided in the middle of the heat insulation layer; A plurality of rubber gaskets which are respectively arranged on the outer end face of the combustion chamber in the front end frame, the rear end frame and the first gap. Reinforcing ribs are respectively fixed on the rubber gaskets, and the top surfaces of the reinforcing ribs are coplanar with the top surface of the heat insulation layer; A heat protection layer which is laid on the heat insulation layer and a plurality of the reinforcing ribs, and one end of the heat protection layer extends out of the side of the rear end frame away from the front end frame; 2. A method for preparing a thermal protection structure of an engine combustion chamber housing as described in claim 1, characterized in that It includes the following steps: Determine the forming positions of the heat insulation layer and the reinforcing ribs; Take the heat insulation layer and paste it along the forming positions along the die surface and bond it to the outer end face of the combustion chamber; Take the rubber gaskets and respectively arrange them on the front end frame, the rear end frame and the outer end face of the combustion chamber according to the forming positions; Take the first pre-impregnated tape and lay or wind it layer by layer on the rubber gaskets to form the reinforcing ribs; Cover a separation film and a vacuum film on the reinforcing ribs and the heat insulation layer in sequence, evacuate until it is shaped and then remove the vacuum film and the separation film; Take the second pre-impregnated tape and lay it layer by layer on the reinforcing ribs and the heat insulation layer to form the heat protection layer. Cover a separation film, a rubber-absorbing paper and a vacuum film on the outside of the heat protection layer in sequence, heat and cure it and then remove the separation film, the rubber-absorbing paper and the vacuum film to obtain the thermal protection structure; 3. The preparation method of the thermal protection structure of the engine combustion chamber housing according to claim 2, characterized in that: The rubber gaskets are subjected to pre-punching treatment before bonding; 4. The preparation method of the thermal protection structure of the engine combustion chamber housing according to claim 3, characterized in that: The punching rate of the rubber gaskets is 25% - 45%; 5. The preparation method of the thermal protection structure of the engine combustion chamber housing according to claim 2, characterized in that: The surface of the rubber gaskets is bonded with a rubber-based adhesive; 6. The preparation method of the thermal protection structure of the engine combustion chamber housing according to claim 2, characterized in that: The heat insulation layer is made of aerogel material; 7. The preparation method of the thermal protection structure of the engine combustion chamber shell according to claim 2, characterized in that: the first pre-impregnated tape is made of microsphere heat insulation material; 8. The preparation method of the thermal protection structure of the engine combustion chamber housing according to claim 2, characterized in that: The second pre-impregnated tape is made of ceramizable material; 9. The preparation method of the thermal protection structure of the engine combustion chamber housing according to claim 2, characterized in that: Remove the flash and trim the shape of the obtained thermal protection structure; 10. The preparation method of the thermal protection structure of the engine combustion chamber housing according to claim 2, characterized in that: The laying or winding direction of the heat insulation layer is consistent with the axis direction of the die.

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