Heat insulation component, heat insulation structure and heat insulation component manufacturing method

Abstract

The invention provides a heat insulation component, a heat insulation structure and a heat insulation component manufacturing method.The heat insulation component comprises a heat insulation bottom plate, a middle heat insulation plate, an upper heat insulation plate and a buffering heat insulation layer arranged between the heat insulation bottom plate and the upper heat insulation plate, and the middle of the buffering heat insulation layer is hollowed out relative to the middle heat insulation plate so as to wrap the middle heat insulation plate; the heat insulation bottom plate, the middle heat insulation plate and the upper heat insulation plate are hard plates, the buffer heat insulation layer is a soft layer, and damp-proof layers are bonded on the surface, provided with the middle heat insulation plate, of the heat insulation bottom plate, four side faces, attached to the buffer heat insulation layer, of the middle heat insulation plate and the surface, not connected with the middle heat insulation plate, of the upper heat insulation plate. After being subjected to a series of low-temperature tests such as high and low temperature impact and pressure alternating fatigue impact, the heat insulation component can still be kept intact, the water dispersion rate is low, the heat insulation performance is excellent, the energy-saving effect is remarkable, and the technical requirement of a low-temperature device for a heat insulation system can be met.

Description

Technical Field

[0001] This invention relates to the field of aerospace cryogenic test equipment technology, specifically to an insulation component, an insulation structure, and a method for manufacturing the insulation component. Background Technology

[0002] A wind tunnel, also known as a wind tunnel laboratory, is a tubular experimental device that artificially generates and controls airflow to simulate the flow of gas around an aircraft or other physical object. It measures the effects of airflow on the object and observes physical phenomena. It is one of the most commonly used and effective tools for conducting aerodynamic experiments. Wind tunnel experiments are an indispensable part of aircraft development and play a crucial role in the research and development of aerospace engineering. The environment of aerospace engineering is a cold, dark space with temperatures around 4K. -8 ~10 -12 The ultra-high vacuum of Pa necessitates that material selection, structural design, and instrumentation all meet the requirements of deep cryogenic and high vacuum. Based on this, cryogenic testing for aerospace applications requires conduction under liquid nitrogen (-163℃), including a series of cryogenic tests such as temperature shock and pressure alternation. The test equipment must be equipped with a thermal insulation protective layer that is resistant to high and low temperature shock, pressure fatigue shock, and pressure alternation shock, with low water dissipation and excellent thermal insulation performance. This poses unprecedented challenges to the material properties, structural design, manufacturing, and installation of thermal insulation components. Patent application number 201811409473.1 discloses a low-temperature, lightweight, low-thermal-conductivity composite insulation structure, comprising a variable-density multilayer insulation component and a foam insulation component bonded together. The variable-density multilayer insulation component is located at the cold end and is used to reduce radiative heat leakage of the composite insulation structure in a vacuum environment. It is composed of a low-thermal-conductivity lightweight spacer and a double-sided aluminized polyester film. The foam insulation component is used to reduce thermal conductivity and heat leakage of the composite insulation structure in an atmospheric pressure environment. However, this composite insulation structure is designed for cryogenic storage tanks in aircraft and does not consider the design performance of pressure fatigue impact and pressure alternating impact, which does not meet the insulation component requirements of cryogenic transonic wind tunnels. Faced with the high technical requirements of cryogenic transonic wind tunnels, existing insulation components and internal insulation systems cannot meet the requirements. Therefore, designing insulation components with low thermal conductivity, resistance to high and low temperatures and pressure alternating impact, and low water dissipation rate is an urgent problem to be solved in current aerospace engineering research. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a thermal insulation component, thermal insulation structure, and manufacturing method of thermal insulation component that are resistant to high and low temperatures and pressure alternating fatigue.

[0004] To achieve the above objectives, the technical solution of the present invention is implemented as follows: According to one aspect of the present invention, a heat insulation component is provided, comprising a heat insulation base plate, an intermediate heat insulation plate, an upper heat insulation plate, and a buffer heat insulation layer disposed between the heat insulation base plate and the upper heat insulation plate, wherein the middle part of the buffer heat insulation layer is hollowed out relative to the intermediate heat insulation plate to cover the intermediate heat insulation plate, wherein the heat insulation base plate, the intermediate heat insulation plate, and the upper heat insulation plate are rigid boards, the buffer heat insulation layer is a soft layer, a moisture-proof layer is bonded to the surface of the heat insulation base plate on which the intermediate heat insulation plate is attached, a moisture-proof layer is bonded to the four sides of the intermediate heat insulation plate that are in contact with the buffer heat insulation layer, and a moisture-proof layer is bonded to the remaining surfaces of the upper heat insulation plate that are not connected to the intermediate heat insulation plate.

[0005] The thermal insulation component of this invention includes a rigid thermal insulation base plate, an intermediate thermal insulation plate, an upper thermal insulation plate, and a soft buffer thermal insulation layer. During a series of low-temperature tests such as temperature shock and pressure alternation, the buffer thermal insulation layer located between the rigid thermal insulation base plate and the upper thermal insulation plate can release stress under temperature difference and prevent damage such as cracking. The product has high reliability and can remain intact after high and low temperature shock and pressure fatigue impact tests. It solves the problem of cracking caused by high stress during the thermal insulation structure test of large test equipment. It has a low water dissipation rate, excellent thermal insulation performance, and significant energy saving effect, which can meet the technical requirements of the thermal insulation system for low-temperature transonic wind tunnels.

[0006] In one embodiment, the heat insulation base plate is an arc-shaped base plate, the surface of the heat insulation base plate that contacts the intermediate heat insulation plate is a plane, and the back surface opposite to the plane is an arc surface. The heat insulation base plate includes two first side surfaces facing each other and two second side surfaces facing each other. The first side surfaces are perpendicular to the surface of the heat insulation base plate, and the second side surfaces form an obtuse angle with the surface of the heat insulation base plate.

[0007] In one embodiment, the angle between the second side surface and the surface ranges from 92.82° to 105°.

[0008] In one embodiment, the outer diameter corresponding to the arc surface of the heat-insulating base plate is 2000-7500mm.

[0009] In one embodiment, the material of the insulating base plate is one of modified PUR rigid insulation material (PUR: polyurethane), PIR insulation material (PIR: polyisocyanate), modified PU insulation material (PU: polyurethane), PI insulation material (PI: polyimide, polyimide resin), and phenolic insulation material; the material of the intermediate insulation plate is one of modified PUR rigid insulation material, PIR insulation material, modified PU insulation material, PI insulation material, and phenolic insulation material; and the material of the upper insulation plate is one of modified PUR rigid insulation material, PIR insulation material, modified PU insulation material, PI insulation material, and phenolic insulation material.

[0010] In one embodiment, the upper insulation board is rectangular in shape, the side length of the upper insulation board is 30-40mm shorter than the side length of the bottom insulation board on the same side, the thickness of the upper insulation board is 20-30mm thinner than the thickness of the bottom insulation board, the thickness of the middle insulation board is 1 / 15 to 1 / 10 of the thickness of the bottom insulation board, and the cross-sectional size of the upper insulation board is 2.4 to 3.1 times the cross-sectional size of the middle insulation board.

[0011] In one embodiment, the moisture-proof layer is composed of an aluminum film and a non-metallic film, wherein the non-metallic film includes one or more of PI film (polyimide film), LDPE (low-density polyethylene), glass fiber reinforced PE (glass fiber reinforced polyethylene), and PP (polypropylene).

[0012] In one embodiment, the four corners of the insulating base plate are recessed inward to form corner cylindrical surfaces, and the axes of the four corner cylindrical surfaces extend and intersect on the side where the upper insulating plate is located.

[0013] According to another aspect of the present invention, a thermal insulation structure is provided, comprising a plurality of thermal insulation components as described in any of the preceding claims, wherein a soft compensating thermal insulation block is filled in the gap between any two adjacent thermal insulation components.

[0014] The thermal insulation structure of this invention remains intact after undergoing high and low temperature impact and pressure fatigue impact tests at a low temperature of -163℃. It has a low water dissipation rate, excellent thermal insulation performance, and significant energy-saving effect, and can meet the technical requirements of low temperature transonic wind tunnels for thermal insulation systems.

[0015] According to another aspect of the present invention, a method for manufacturing a thermal insulation component is provided, for manufacturing a thermal insulation component as described in any of the preceding claims, comprising: (1) Design drawings including the specific dimensions of the insulation base plate, intermediate insulation plate, upper insulation plate, buffer insulation layer and moisture-proof layer; (2) Blanking: The insulation base plate, the middle insulation plate and the upper insulation plate are processed from the rigid insulation material blank according to the design drawings using wire cutting equipment; the buffer insulation layer is processed from the soft insulation material blank according to the design drawings. (3) The moisture-proof layers of the insulation base plate, the intermediate insulation plate and the upper insulation plate are respectively processed using a vibrating knife equipment according to the design drawings; (4) Use a vacuum cleaner to clean the insulation base plate, the intermediate insulation plate, the upper insulation plate and the moisture-proof layer respectively to ensure that no dust adheres to the components; (5) Cover the corresponding moisture-proof layer on the insulation base plate, the intermediate insulation plate and the upper insulation plate according to the design drawings. First, apply a low-temperature adhesive with a thickness of 0.1-0.3mm to the surface to be covered, and then lay the moisture-proof layer. (6) The insulation base plate, the middle insulation plate and the upper insulation plate that have been covered with moisture-proof layer are respectively put into vacuum bags, and then the whole thing is put into a vacuum equipment. Keep it under vacuum for 2-3 minutes, and then take it out and keep it under pressure for 5-7 hours at room temperature. (7) Apply low-temperature adhesive to the surfaces to be bonded of the buffer insulation layer, the cured insulation base plate, the intermediate insulation plate, and the upper insulation plate in sequence. Bond the intermediate insulation plate and the buffer insulation layer to the top of the insulation base plate. Then bond the upper insulation plate to the top of the intermediate insulation plate and the buffer insulation layer. Then place it in a pressure fixture for pressure curing. The pressure conditions are 2.0T-2.8T and the time is 4-6h. (8) Remove the pressure, take it out, and clean the excess adhesive from the bonding area to obtain the heat insulation component.

[0016] The method for manufacturing thermal insulation components of the present invention involves multiple processes such as cutting rigid thermal insulation materials, soft thermal insulation materials, moisture-proof layer, pretreatment, moisture-proof layer laying, vacuum pressing and curing, composite, and post-treatment. The process is relatively simple, the production efficiency is high, and the resulting thermal insulation components have excellent performance in resisting high and low temperatures and pressure alternating fatigue.

[0017] The thermal insulation component of this invention includes a rigid thermal insulation base plate, an intermediate thermal insulation plate, an upper thermal insulation plate, and a soft buffer thermal insulation layer. During a series of low-temperature tests, such as temperature shock and pressure alternation, the unique material arrangement and structural design of the thermal insulation component allow the thermal insulation base plate, intermediate thermal insulation plate, upper thermal insulation plate, and the central buffer thermal insulation layer to release stress under large temperature differences and prevent cracking and other damage. The thermal insulation structure based on this component remains intact after high and low temperature shock and pressure fatigue shock tests at -163℃, solving the problem of cracking caused by high stress during the thermal insulation structure test of large test devices. At the same time, the internal thermal insulation system has a low water dissipation rate, excellent thermal insulation performance, significant energy-saving effect, and high product reliability, which can meet the technical requirements of the thermal insulation system for low-temperature transonic wind tunnels. Furthermore, the manufacturing method of the thermal insulation component is relatively simple and has high production efficiency.

[0018] Other advantages of the present invention will be described in detail in the following detailed description section with reference to the accompanying drawings. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0020] In the attached diagram: Figure 1 This is a front view schematic diagram of an embodiment of the thermal insulation component of the present invention; Figure 2 for Figure 1 A cross-sectional view of the insulation component shown. Figure 3 for Figure 1 The diagram shows a three-dimensional structure of the insulation component installed on the inner wall of the metal cylinder. Figure 4 The temperature distribution and heat flux distribution of the standard insulation unit are given when the internal temperature of the cave is -163℃ and the ambient temperature is 32.6℃; where (a) is the temperature distribution, (b) is the cross-sectional temperature distribution, and (c) is the heat flux distribution on the surface of the cave. Figure 5 The temperature distribution of a unit block is shown when the surface temperature of the cave is 32.6℃ and the airflow temperature in the cave is -123℃; where (a) is the initial temperature field and (b) is the temperature field after 15s. Figure 6 The diagram shows the thermal stress distribution of a standard insulation unit when the internal temperature of the cave is -163℃ and the ambient temperature is 32.6℃. Among them, (a) is the overall stress distribution of the insulation component, (b) is the stress distribution of the upper insulation material, (c) is the stress distribution of the middle insulation material, and (d) is the stress distribution of the lower insulation material. Figure 7The thermal stress distribution diagram of the standard insulation unit is shown when the airflow temperature inside the cave is -163℃ and a positive pressure load (0.5MPa) is applied to the surface of the internal insulation system. Among them, (a) is the overall stress distribution of the insulation component, (b) is the stress distribution of the upper insulation material, (c) is the stress distribution of the middle insulation material, and (d) is the stress distribution of the lower insulation material. Figure 8 The diagram shows the thermal stress distribution of a standard insulation unit when the airflow temperature is -163℃ and the pressure relief rate is 80kPa / s. Among them, (a) is the overall stress distribution of the insulation component, (b) is the stress distribution of the upper insulation material, (c) is the stress distribution of the middle insulation material, and (d) is the stress distribution of the lower insulation material. Figure 9 The diagram shows the thermal stress distribution of a standard insulation unit when the airflow temperature is -163℃ and the pressure rise rate is 30kPa / s. Among them, (a) is the overall stress distribution of the insulation component, (b) is the stress distribution of the upper insulation material, (c) is the stress distribution of the middle insulation material, and (d) is the stress distribution of the lower insulation material. Figure 10 A cross-sectional view showing the assembly of adjacent insulation components; Figure 11 This is a schematic diagram of the cylinder of the low-temperature test platform; Figure 12 This is a schematic diagram showing the layout of 7 measuring points on the insulation structure. Figure 13 This is a temperature distribution diagram of various measuring points on an insulating component under low-temperature pressure alternating fatigue conditions.

[0021] Explanation of reference numerals in the attached diagram: 1. Insulation base plate; 2. Intermediate insulation plate; 3. Upper insulation plate; 4. Buffer insulation layer; 5. Moisture-proof layer; 6. End corner cylindrical surface; 7. Compensating insulation block; 8. Inner wall of metal cylinder. Detailed Implementation

[0022] To further explain the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings, in which the same reference numerals denote the same parts.

[0023] Example 1 like Figure 1-3As shown, this embodiment provides a heat insulation component, including a rigid heat insulation base plate 1, an intermediate heat insulation plate 2, an upper heat insulation plate 3, and an elastic soft buffer heat insulation layer 4. The intermediate heat insulation plate 2 and the upper heat insulation plate 3 are stacked sequentially on the surface of the heat insulation base plate 1. The upper and lower surfaces of the intermediate heat insulation plate 2 are bonded to the upper heat insulation plate 3 and the heat insulation base plate 1, respectively. The buffer heat insulation layer 4 is disposed between the heat insulation base plate 1 and the upper heat insulation plate 3, and its middle part is hollowed out relative to the intermediate heat insulation plate 2 to cover the intermediate heat insulation plate 2. The size of the hollowed-out part on the buffer heat insulation layer 4 is equivalent to the size of the intermediate heat insulation plate 2. The insulating base plate 1 is an arc-shaped base plate. The surface of the insulating base plate 1 that contacts the intermediate insulating plate 2 is flat, and the back surface opposite to this flat surface (i.e., the surface of the intermediate insulating plate 2) is arc-shaped. The outer diameter of the arc-shaped surface is 6000mm. The insulating base plate 1 includes a first side facing each other and two second side facing each other. The first side is perpendicular to the surface of the intermediate insulating plate 2 of the insulating base plate 1, and the second side is inclined outward relative to the surface of the intermediate insulating plate 2 of the insulating base plate 1. The angle between the second side and the surface of the intermediate insulating plate 2 of the insulating base plate 1 is within the range of 93.75°. The arc-shaped back surface of the insulating base plate 1 can better fit the cylindrical inner wall of the low-temperature test device. At the same time, the two opposite second side surfaces that are inclined outward relative to the flat surface are designed on the insulating base plate 1, which can make the insulating base plates 1 of adjacent insulating components fit tightly on the cylindrical inner wall of the low-temperature test device.

[0024] In this embodiment, the main components of the insulating base plate 1, the intermediate insulating plate 2, and the upper insulating plate 3 are modified PUR rigid insulating materials, while the buffer insulating layer 4 is made of a soft insulating material, such as PI soft foam, PU foam, or EPDM foam. The insulating base plate 1 has a moisture-proof layer adhered to the surface of the intermediate insulating plate 2. Moisture-proof layers are also adhered to the four sides of the intermediate insulating plate 2 that are in contact with the buffer insulating layer 4. On all surfaces of the upper insulating plate 3, except for the area connected to the intermediate insulating plate 2, a moisture-proof layer 5 is adhered. The moisture-proof layers between adjacent end faces of the upper insulating plate 3 are connected by overlapping or butt joints, with an overlap width of 3mm. The moisture-proof layers on the surfaces of the insulating base plate 1, intermediate insulating plate 2, and upper insulating plate 3 are composed of an aluminum film and a PI film (non-metallic film). In other embodiments, the moisture-proof layer can also be composed of an aluminum film and a glass fiber reinforced PE film (non-metallic film).

[0025] In this embodiment, the upper insulation plate 3 is rectangular in shape. The side length of the upper insulation plate 3 is 30mm shorter than the side length of the insulation base plate 1 on the same side. The thickness of the upper insulation plate 3 is 28mm thinner than the thickness of the insulation base plate 1. The thickness of the middle insulation plate 2 is 1 / 15 of the thickness of the insulation base plate 1. The cross-sectional size of the upper insulation plate 3 is 2.5 times the cross-sectional size of the middle insulation plate 2.

[0026] like Figure 3As shown, in this embodiment, the back of the heat insulation base plate 1 is bonded and fixed to the inner wall 8 of the metal cylinder with a flexible low-temperature resistant adhesive to maintain the back of the heat insulation base plate 1 at room temperature. The four corners of the heat insulation base plate 1 are recessed inward to form corner cylindrical surfaces 6. The axes of the four corner cylindrical surfaces 6 extend and intersect on the side where the upper heat insulation plate 3 is located. The axis of the corner cylindrical surface 6 and the surface of the heat insulation plate 2 in the middle of the contact between the heat insulation base plate 1 and the heat insulation base plate 1 form an acute angle of 86.25°. After the heat insulation component is bonded and fixed to the inner wall 8 of the metal cylinder with a flexible low-temperature resistant adhesive, it serves as a heat insulation functional component. A metal support layer is also connected to its surface. The metal support layer is connected to the inner wall 8 of the metal cylinder through support studs. The four corner cylindrical surfaces 6 of the heat insulation base plate 1 are used to cooperate with the support stud installation structure to facilitate the installation of the metal support layer. In other embodiments, the line-plane angle between the axis of the end-corner cylindrical surface 6 and the surface of the adhesive intermediate insulation board 2 of the insulation base plate 1 ranges from 82.5 to 87.18°, or is 75°.

[0027] Simulation analysis was performed on the insulation component of Example 1, and a unit consisting of an insulation component, its directly opposite metal cylinder inner wall, and a metal support layer was taken as a standard insulation unit: 1.1 Steady-state heat transfer condition 1) When the internal temperature of the wind tunnel is -163℃ and the ambient temperature is 32.6℃, the temperature field analysis results of the standard insulation unit show that the lowest temperature on the outer surface of the tunnel is 25.62℃, and the highest temperature is 26.56℃. Under this condition, the average heat flux of the standard insulation unit on the tunnel surface is 31.36 W / m². 2 ,like Figure 4 As shown.

[0028] 1.2 Transient heat transfer conditions Transient analysis, calculation conditions: surface temperature of the cave is 32.6℃, and the airflow temperature inside the cave is -123℃; the airflow temperature inside the cave drops from -123℃ to -163℃ at a rate of 3℃ / s.

[0029] The temperature distribution of a single block when the surface temperature of the cave is 32.6℃ and the airflow temperature is -123℃ is as follows: Figure 5 As shown, the upper surface temperature of the protective plate and the internal insulation system both reached a steady state of -123℃, and the surface temperature of the cave was 26.3℃. When the airflow temperature inside the cave decreased from -123℃ to -163℃ at a rate of 3℃ / s, after 15s of transient analysis, the inner surface temperature of the internal insulation system decreased by 3.6℃, ​​while the outer surface temperature of the insulation layer remained unchanged.

[0030] 1.3 Temperature-related strength verification 1) When the internal temperature of the cavern is -163℃ and the ambient temperature is 32.6℃, the thermal stress analysis results of the standard insulation unit show that the maximum stress of the upper insulation material is 1.03MPa, the maximum stress of the middle insulation material is 1.01MPa, and the maximum stress of the lower insulation material is 0.95MPa. Figure 6 As shown in Table 1, the safety factor statistics for each insulation layer are presented.

[0031] Table 1 Safety Factor Table (Internal temperature of the cave is -163℃, ambient temperature is 32.6℃)

[0032] 1.4 Strength Verification under Combined Temperature and Pressure Conditions The temperature and pressure combination conditions of the insulation unit are the most demanding, so the strength of the insulation unit under low temperature + positive pressure load (0.5MPa) is evaluated in detail.

[0033] The airflow temperature inside the cavern is -163℃. A positive pressure load (0.5MPa) is applied to the surface of the internal insulation system. Stress analysis results show that the maximum stress in the upper insulation material is 0.17MPa, the maximum stress in the middle insulation material is 1.14MPa, and the maximum stress in the lower insulation material is 0.88MPa. Figure 7 As shown in Table 2, the safety factor statistics for each insulation layer are presented.

[0034] Table 2 Safety Factor Table (Airflow temperature inside the cave is -163℃, with a positive pressure load of 0.5MPa applied to the surface of the internal insulation system)

[0035] 1.5 Special Working Conditions 1) The airflow temperature is -163℃, and the pressure relief rate is 80 kPa / s. Analysis results show that the maximum stress in the upper insulation material is 0.667 MPa, the maximum stress in the middle insulation material is 0.368 MPa, and the maximum stress in the lower insulation material is 0.391 MPa. All are below the material's tensile strength of 2.2 MPa, with a minimum safety factor of 3.3. The stress distribution cloud diagram is shown below. Figure 8 As shown.

[0036] 2) The airflow temperature was -163℃, and the pressure increase rate was 30 kPa / s. Analysis results show that the maximum stress in the upper insulation material was 0.661 MPa, the maximum stress in the middle insulation material was 0.379 MPa, and the maximum stress in the lower insulation material was 0.389 MPa. All are below the material tensile strength of 2.2 MPa, with a minimum safety factor of 3.33. The stress distribution cloud diagram is shown below. Figure 9 As shown.

[0037] Based on the simulation results above, it can be seen that the thermal insulation components of this embodiment, including a rigid thermal insulation base plate (i.e., the lower thermal insulation material), a rigid intermediate thermal insulation plate, a soft buffer thermal insulation layer (i.e., the intermediate thermal insulation material), and a rigid upper thermal insulation plate (i.e., the upper thermal insulation material), can remain intact after high and low temperature impact and pressure fatigue impact tests. This solves the problem of cracking caused by high stress during the thermal insulation structure test of large test devices. It has a low water diffusion rate, excellent thermal insulation performance, and significant energy-saving effect, which can meet the technical requirements of the thermal insulation system for low temperature transonic wind tunnels.

[0038] Example 2 This embodiment provides a thermal insulation structure, including several such as Figure 1 The insulation components shown are, for example Figure 10 As shown, the gap between any two adjacent insulation components is filled with compensating insulation blocks 7.

[0039] The compensating insulation block 7 is a soft insulation material used to seal the joints between adjacent insulation base plates 1 and to fill the gaps between adjacent upper insulation plates 3 and between adjacent buffer insulation layers 4. Several insulation components are bonded and fixed to the inner wall 8 of the metal cylinder to form a whole-surface insulation structure. The compensating insulation blocks 7 filling the gaps between any adjacent insulation components constitute the transverse and longitudinal compensating blocks of the entire insulation structure. During a series of low-temperature tests such as temperature shock and pressure alternation, the buffer insulation layer 4 and the compensating insulation block 7 play the role of releasing stress under temperature difference and preventing cracking and other damage.

[0040] Thermal insulation performance tests were conducted on the thermal insulation structure of this embodiment: 1.1 Test Specimen Referring to the test chamber in the low-temperature test platform, a test specimen cylinder with a diameter of Φ2200mm × 2200mm was fabricated. The cylinder material was 304L stainless steel, used to simulate the wind tunnel structure, such as... Figure 11 As shown.

[0041] 1.2 Experimental Conditions The cryogenic test platform is capable of maintaining the low temperature inside the cylinder, as well as pressurizing and holding the pressure at low temperatures. It primarily employs liquid nitrogen cooling and dry nitrogen pressurization methods. The required test conditions are as follows: 1) Experimental media: ambient temperature air, ambient temperature nitrogen, and low temperature nitrogen; 2) Medium flow velocity: 0-5 m / s; 3) Experimental temperature: 110-300K; 4) Experimental pressure: 0.01MPa-0.45MPa; 5) Maximum pressure boost rate: 30 kPa / s; 6) Maximum pressure drop rate: 80 kPa / s.

[0042] 1.3 Measurement Data Acquisition Methods The "7-point monitoring" system is mainly deployed at the intermediate compensation layer (i.e., buffer insulation layer 4), the intermediate insulation layer (i.e., intermediate insulation board 2), and the joint locations of the insulation structure, such as... Figure 12 As shown, measuring points ① were arranged on the upper surface of the insulation component; ② were arranged on the upper surface of the joint structure; ③ were arranged at the junction of the middle insulation layer and the lower insulation layer (i.e., insulation base plate 1) of the insulation structure; ④ were arranged at the bonding point between the lower insulation layer and the cavity wall of the insulation structure; ⑤ were arranged at the junction of the middle compensation layer and the middle insulation layer of the insulation structure; ⑥ were arranged along the length of the insulation structure at the bottom of the joint; and ⑦ were arranged at the junction of the lower insulation layer and the cavity wall of two adjacent insulation structures. A total of 7 thermocouples were arranged in this section, and 12 thermocouples were arranged in this manner throughout the entire test specimen cylinder.

[0043] 1.4 Experimental Results During the cold and pressure test, no frost appeared on the outer surface of the cylinder. Figure 13 The test data are from the low-temperature pressure alternating fatigue condition test data. Figure 13 It can be seen that the surface temperature of the insulation component (measuring point ①) is the lowest, which is the low-temperature ambient temperature of 110K; the temperature on the outer side of the cylinder wall (measuring point ④) is the highest, consistent with the ambient temperature; the lowest temperature on the upper surface of the bottom insulation layer (measuring point ⑤) is 160K, indicating that the temperature distribution gradient in the thickness direction of the insulation component is not large and is relatively uniform. This shows that the insulation component has a good cold preservation effect at low temperatures, meeting the design requirements.

[0044] During the test, no frost was observed on the outer surface of the cylinder and the corresponding positions of the insulation components and compensation parts. After the test, the cylinder was opened and the internal appearance of the cylinder was basically unchanged. No defects such as cracking or blistering were found in the insulation components and compensation parts, and no defects such as bulging or falling off were found on the bonding surface.

[0045] 1.5 Conclusion No frost formation occurred during the test, and the temperature distribution was consistent with the actual situation. Under the most demanding low-temperature pressure alternating conditions, the insulation structure did not crack, and the surface condition of the moisture-proof layer was good. This indicates that the structure, materials, manufacturing, and installation of the standard insulation unit meet all working conditions and satisfy the insulation performance requirements.

[0046] Example 3 This embodiment provides a method for manufacturing thermal insulation components, used to manufacture... Figure 1 The insulation component shown includes: (1) Design drawings including the specific dimensions of the insulation base plate, intermediate insulation plate, upper insulation plate, buffer insulation layer and moisture-proof layer; (2) Blanking: The insulation base plate, the middle insulation plate and the upper insulation plate are processed from the rigid insulation material blank according to the design drawings using wire cutting equipment. The buffer insulation layer is processed from the soft insulation material blank according to the design drawings. (3) According to the design drawings, the moisture-proof layer of the insulation base plate, the middle insulation plate and the upper insulation plate shall be processed by vibrating knife equipment respectively, and the moisture-proof layer shall be free of wrinkles, scratches and the like. (4) Use a vacuum cleaner to clean the insulation base plate, the middle insulation plate, the upper insulation plate and the moisture-proof layer respectively. The vacuum cleaner should be used at least twice and there should be no dust adhering to the parts. (5) Cover the corresponding moisture-proof layer on the insulation base plate, intermediate insulation plate and upper insulation plate according to the design drawings. First, apply a low temperature adhesive with a thickness of 0.2mm to the surface to be covered, and then lay the moisture-proof layer. The adhesive should be applied evenly. Lay the moisture-proof layer slowly from one side until it is fully covered. (6) The insulation base plate, intermediate insulation plate and upper insulation plate that have been covered with moisture-proof layer are put into vacuum bags respectively, and then the whole thing is put into a vacuum equipment, kept under vacuum for 3 minutes, and then taken out and kept under pressure for 6 hours at room temperature. (7) Apply low-temperature adhesive to the surfaces to be bonded in sequence, including the buffer insulation layer, the cured insulation base plate, the intermediate insulation plate, and the upper insulation plate. Bond the intermediate insulation plate and the buffer insulation layer to the top of the insulation base plate. Then bond the upper insulation plate to the top of the intermediate insulation plate and the buffer insulation layer. Then place it in a pressure fixture for pressure curing. The pressure condition is 2.4T and the time is 5h. (8) Remove the pressure, take it out, and clean the excess adhesive from the bonding area to obtain the heat insulation component.

[0047] In this embodiment, the buffer insulation layer 4 between the insulation base plate 1 and the upper insulation plate 3 is made as a component of a single insulation component along with the single insulation component. The single finished insulation component is installed on the inner wall of the low temperature test device. Then, the gaps between any adjacent insulation components are filled with compensation insulation blocks 7 to form the transverse and longitudinal compensation blocks of the entire insulation structure. The transverse and longitudinal compensation blocks of the entire insulation structure and all insulation components together form the insulation system in the low temperature test device.

[0048] Compared with existing technologies, the thermal insulation component provided by this invention includes a rigid thermal insulation base plate, an intermediate thermal insulation plate, an upper thermal insulation plate, and a soft buffer thermal insulation layer. During a series of low-temperature tests, such as temperature shock and pressure alternation, the unique material arrangement and structural design of the thermal insulation component allow the thermal insulation base plate, intermediate thermal insulation plate, upper thermal insulation plate, and the central buffer thermal insulation layer to release stress under large temperature differences and prevent cracking and other damage. The thermal insulation structure based on this component remains intact after high and low temperature shock and pressure fatigue shock tests at -163℃, solving the cracking problem caused by high stress during the thermal insulation structure testing of large-scale testing devices. Simultaneously, the internal thermal insulation system has a low water dissipation rate, excellent thermal insulation performance, significant energy-saving effect, and high product reliability, meeting the technical requirements of low-temperature transonic wind tunnels for thermal insulation systems. Furthermore, the manufacturing method of the thermal insulation component is relatively simple and has high production efficiency.

[0049] The above description is merely a specific embodiment of the present invention. It should be noted that any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the protection scope of the present invention.

Claims

1. A thermal insulating member characterized by, The heat insulation bottom plate (1), the intermediate heat insulation plate (2), and the upper heat insulation plate (3) are hard plates, and the buffer heat insulation layer (4) is a soft layer.

2. The thermal insulating member according to claim 1, wherein The heat insulation bottom plate (1) is an arc-shaped bottom plate, the surface of the heat insulation bottom plate (1) that contacts the intermediate heat insulation plate (2) is a plane, the back surface opposite to the plane is an arc surface, the heat insulation bottom plate (1) comprises two first opposite sides and two second opposite sides, the first side is perpendicular to the surface of the heat insulation bottom plate (1), and the second side forms an obtuse angle with the surface of the heat insulation bottom plate (1).

3. The thermal insulating member according to claim 2, wherein The included angle between the second side and the surface ranges from 92.82° to 105°.

4. The thermal insulating member according to claim 2, wherein The outer diameter corresponding to the arc surface of the heat insulation bottom plate (1) ranges from 2000 mm to 7500 mm.

5. A thermal insulation element according to any one of claims 1-4, c h a r a c t e r i z e d in that The material of the heat insulation bottom plate (1) is one of modified PUR hard insulation material, PIR insulation material, modified PU insulation material, PI insulation material, and phenolic insulation material, the material of the intermediate heat insulation plate (2) is one of modified PUR hard insulation material, PIR insulation material, modified PU insulation material, PI insulation material, and phenolic insulation material, and the material of the upper heat insulation plate (3) is one of modified PUR hard insulation material, PIR insulation material, modified PU insulation material, PI insulation material, and phenolic insulation material.

6. A thermal insulation element according to any one of claims 1-4, c h a r a c t e r i z e d in that The upper heat insulation plate (3) is a cuboid, the side length of the upper heat insulation plate (3) is 30-40 mm shorter than the side length of the heat insulation bottom plate (1) on the same side, the thickness of the upper heat insulation plate (3) is 20-30 mm thinner than the thickness of the heat insulation bottom plate (1), the thickness of the intermediate heat insulation plate (2) is 1 / 15-1 / 10 of the thickness of the heat insulation bottom plate (1), and the cross-sectional size of the upper heat insulation plate (3) is 2.4-3.1 times the cross-sectional size of the intermediate heat insulation plate (2).

7. A thermal insulating member according to any one of claims 1 to 4, wherein The moisture-proof layer is composed of an aluminum film and a non-metal film, and the non-metal film comprises one or more of PI film, LDPE, glass fiber reinforced PE, and PP.

8. A thermal insulating member according to any one of claims 1 to 4, wherein The four end corners of the heat insulation bottom plate (1) are inwardly recessed to form end corner cylindrical surfaces (6), and the axes of the four end corner cylindrical surfaces (6) extend and intersect on the side where the upper heat insulation plate (3) is located.

9. A thermally insulating structure, characterized by The heat insulation structure comprises a plurality of heat insulation members as claimed in any one of claims 1-8, and a soft compensating heat insulation block (7) is filled in the gap between any two adjacent heat insulation members.

10. A method for manufacturing a thermal insulating member according to any one of claims 1 to 8, characterized by, The heat insulation structure comprises (1) design drawings including the specific size of the design of the heat insulation bottom plate, intermediate heat insulation plate, upper heat insulation plate, buffer insulation layer and moisture-proof layer; (2) blanking: from the hard heat insulation material blank, using a wire cutting equipment according to the design drawings to process the heat insulation bottom plate, intermediate heat insulation plate and upper heat insulation plate, and from the soft heat insulation material blank according to the design drawings to process the buffer insulation layer; (3) according to the design drawings, using a vibrating knife equipment to process the moisture-proof layer of the heat insulation bottom plate, the intermediate heat insulation plate and the upper heat insulation plate respectively; (4) using a dust collector to clean the heat insulation bottom plate, the intermediate heat insulation plate, the upper heat insulation plate and the moisture-proof layer respectively, so that the parts are free of dust adhesion; (5) according to the design drawings, coating the corresponding moisture-proof layer on the heat insulation bottom plate, the intermediate heat insulation plate and the upper heat insulation plate, first brushing a low-temperature adhesive with a thickness of 0.1-0.3mm on the surface to be coated, and then laying the moisture-proof layer; (6) the heat insulation bottom plate, the intermediate heat insulation plate and the upper heat insulation plate with the moisture-proof layer coated are respectively put into a vacuum bag, and then put into a vacuum extraction equipment as a whole, and kept under vacuum for 2-3min, and then taken out and pressure-cured at room temperature for 5-7h; (7) the buffer insulation layer and the adhesive-coated surfaces of the heat insulation bottom plate, the intermediate heat insulation plate and the upper heat insulation plate are sequentially coated with a low-temperature adhesive, the intermediate heat insulation plate and the buffer insulation layer are bonded on the heat insulation bottom plate, and then the upper heat insulation plate is bonded on the intermediate heat insulation plate and the buffer insulation layer, and then placed in a pressurized tool for pressure curing, the pressure condition is 2.0T-2.8T, and the time is 4-6h; (8) remove the pressure, take out, and remove the excess adhesive at the bonding site, and the heat insulation component is obtained.

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