An airborne liquid hydrogen storage tank and fuselage connection structure and aircraft

Abstract

The utility model relates to an airborne liquid hydrogen storage tank and fuselage connecting structure and airplane, and the structure includes: front clamp assembly, rear clamp assembly, heat insulation subassembly and adjusting protection subassembly, the connecting structure is used to connect the airborne liquid hydrogen storage tank and fuselage in it, and the connecting structure passes through the high density foam with certain heat insulation performance to contact mode transmission load, avoids the main structure of the storage tank contacted with liquid hydrogen and the fuselage skin to be directly connected through the connecting structure, effectively reduces the heat exchange of the storage tank and the outside world, simultaneously, the main structure of the storage tank and the fuselage skin do not adopt rigid mechanical connection, reduce the main structure in the liquid hydrogen temperature zone temperature load influence, make the stress condition of the main structure of the storage tank under temperature and internal pressure load be influenced less by the connecting mode, can avoid the stress concentration phenomenon when mechanical connection, secondly, the main structure of the storage tank adopts the reinforcing member set up around its main body, can realize the reliable transmission of liquid hydrogen storage tank heading overload load to the fuselage.

Description

Technical Field

[0001] This utility model belongs to the technical field of aircraft airframe structure design and energy storage structure design, specifically relating to an airborne liquid hydrogen storage tank connection structure with the airframe and an aircraft. Background Technology

[0002] Liquid hydrogen fuel-powered aircraft use liquid hydrogen fuel instead of conventional fuels, offering advantages such as high energy density per unit mass. This reduces carbon emissions, mitigates the greenhouse effect, and reduces NOx emissions by over 80%. However, due to the low volumetric energy density and large volume of liquid hydrogen fuel, placing the liquid hydrogen storage tank within the fuselage is a viable option. Ground-based and vehicle-mounted liquid hydrogen tanks require low evaporation rates and are typically heavy, while airborne liquid hydrogen tanks require both low weight and a moderate evaporation rate. Currently, there are no better solutions for insulation. Furthermore, as a significant point of mass, the airborne liquid hydrogen tank requires optimized structural design, both internally and externally, to ensure reliable connection, transfer of azimuth, vertical, and lateral overloads, and minimize heat leakage through the connection structure, thus maintaining optimal evaporation rate performance. However, no technology currently exists to achieve this.

[0003] The prior art (US20150336680A1) is an aircraft with a tail engine and a large swept-back wing, and a liquid hydrogen storage tank is arranged in the rear fuselage, but it does not describe the aircraft and storage tank scheme, nor does it involve the connection method between the storage tank and the fuselage.

[0004] Existing technology 2 (CN118188749 A) ​​is a double-layered liquid hydrogen storage tank, which is connected to the base through the outer structure of the storage tank, but there is no design description regarding the overload situation in three directions of the storage tank;

[0005] The prior art (CN110486614 A) is a liquid hydrogen storage tank for hydrogen energy vehicles. It describes the buffer design in the connection scheme between the liquid hydrogen storage tank and the support base, but does not explain the design scheme of the storage tank corresponding to the circular fixed frame, nor does it describe the design under the overload conditions in three directions of the storage tank. Utility Model Content

[0006] In order to overcome the above-mentioned problems in the prior art, this utility model provides an airborne liquid hydrogen storage tank and airframe connection structure and an aircraft, which solves the above-mentioned problems in the prior art.

[0007] A connection structure between an airborne liquid hydrogen storage tank and an aircraft fuselage, the structure comprising: a front clamp assembly, a rear clamp assembly, and a heat insulation assembly;

[0008] The airborne liquid hydrogen storage tank includes a main body and a reinforcing member, the reinforcing member covering the main body;

[0009] The front clamp assembly is mounted on the irregularly shaped component of the reinforcing member on the front side of the airborne liquid hydrogen storage tank;

[0010] The rear clamp assembly is located on the rear side of the airborne liquid hydrogen storage tank;

[0011] The first thermal insulation component covers the main body of the airborne liquid hydrogen storage tank;

[0012] The second thermal insulation component is disposed between the front clamp component and the irregular component;

[0013] The third insulation component is disposed between the rear clamp component and the reinforcing area of ​​the reinforcing member, and the second and third insulation components divide the first insulation component into three parts.

[0014] The first insulation component has different performance characteristics from the second and third insulation components.

[0015] In addition to the aspects and any possible implementations described above, a further implementation is provided in which the irregularly shaped component is U-shaped or L-shaped, and when it is U-shaped, it includes a bottom edge and two vertical edges disposed on the bottom edge.

[0016] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the front clamp assembly includes a front upper clamp and a front lower clamp.

[0017] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the rear clamp assembly includes a rear upper clamp and a rear lower clamp.

[0018] In addition to the aspects and any possible implementations described above, a further implementation is provided in which both the upper front clamp and the lower front clamp include a front side, a bottom surface, a rear side, a connecting plate, and a support plate, wherein the front side and the rear side are disposed on both sides of the bottom surface; the connecting plate is disposed on both ends of the bottom surface; and a plurality of the support plates are disposed at the bottom end of the bottom surface.

[0019] In addition to the aspects and any possible implementations described above, a further implementation is provided in which both the upper rear clamp and the lower rear clamp include a front side, a bottom surface, a rear side, a connecting plate, and a flange. The front side and the rear side are disposed on both sides of the bottom surface, the connecting plate is disposed at both ends of the bottom surface, and the flanges are respectively disposed on the front side and the rear side.

[0020] In addition to the aspects described above and any possible implementations, a further implementation is provided, which further includes an adjustment and protection component disposed between the clamp assembly and the insulation assembly.

[0021] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the adjusting and protective component comprises a plurality of rubber strips.

[0022] This utility model also provides an aircraft, which includes an airborne liquid hydrogen storage tank and the aforementioned connecting structure, wherein the connecting structure fixes the airborne liquid hydrogen storage tank to the upper and lower skins of the aircraft.

[0023] In addition to the aspects and any possible implementations described above, a further implementation is provided in which both the upper and lower skins are semi-cylindrical and are connected by overlapping.

[0024] Beneficial effects of this utility model

[0025] This invention relates to a connection structure between an airborne liquid hydrogen storage tank and an aircraft fuselage, and the aircraft itself. The structure includes a front clamp assembly, a rear clamp assembly, a thermal insulation assembly, and an adjustment and protection assembly. The airborne liquid hydrogen storage tank is connected to the fuselage using this connection structure. This connection structure uses high-density foam with certain thermal insulation properties to transfer loads through contact, avoiding direct connection between the main structure of the storage tank (which is in contact with liquid hydrogen) and the fuselage skin via the connection structure, effectively reducing heat exchange between the storage tank and the outside environment. Simultaneously, the main structure of the storage tank is not rigidly mechanically connected to the fuselage skin, reducing the impact of temperature loads on the main structure in the liquid hydrogen temperature range. This makes the stress condition of the main structure of the storage tank under temperature and internal pressure loads less affected by the connection method, avoiding stress concentration phenomena that occur with mechanical connections. Furthermore, the main structure of the storage tank uses reinforced irregularly shaped components, which can reliably transfer the directional overload load of the liquid hydrogen storage tank to the fuselage. By adopting a contact load transfer method, the main structure, clamps, and body skin of the storage tank are all subjected to relatively small stresses under temperature loads. This achieves the coupling between the stress generated by temperature loads and the stress generated by overload loads when no mechanical connection is generated, and the thermal insulation performance is good. Attached Figure Description

[0026] Figure 1 This is a cross-sectional view of the liquid hydrogen storage tank and its connecting structure according to the present invention.

[0027] Figure 2 This is the main structure of the foam-stabilized insulated liquid hydrogen storage tank of this utility model;

[0028] Figure 3 This is a schematic diagram of the foam insulation structure of the foam-stabilized liquid hydrogen storage tank of this utility model.

[0029] Figure 4 This is a schematic diagram of the front lower clamp and rear lower clamp structure of this utility model;

[0030] Figure 5This is a schematic diagram of the front upper clamp and rear upper clamp structure of this utility model;

[0031] Figure 6 This is a schematic diagram of the lower skin structure of this utility model;

[0032] Figure 7 This is a schematic diagram of the upper skin structure of this utility model;

[0033] Figure 8 This is a schematic diagram of the adhesive strip structure of this utility model;

[0034] Figure 9 This is a schematic diagram showing the front lower clamp and rear lower clamp of this utility model being assembled onto the lower skin respectively;

[0035] Figure 10 This is a schematic diagram showing the storage tank of this utility model placed at the lower clamp position;

[0036] Figure 11 This is a schematic diagram showing the connection of the front clamp and the rear clamp of this utility model;

[0037] Figure 12 This is a schematic diagram showing the connection between the upper and lower skins of this utility model.

[0038] Figure 13 This is a schematic diagram illustrating the arrangement of the reinforcing member in this utility model;

[0039] Figure 14 This is a schematic diagram of the upper rear clamp and lower rear clamp structure of this utility model. Detailed Implementation

[0040] To better understand the technical solution of this utility model, the content of this utility model includes, but is not limited to, the specific embodiments described below. Similar technologies and methods should be considered within the scope of protection of this utility model. To make the technical problem to be solved, the technical solution, and the advantages of this utility model clearer, a detailed description will be provided below in conjunction with the accompanying drawings and specific embodiments.

[0041] It should be understood that the embodiments described in this utility model are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0042] The terminology used in the embodiments of this utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The singular forms “a,” “the,” and “the” used in the embodiments of this utility model and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0043] This utility model provides a structure comprising: a front clamp assembly, a rear clamp assembly, and a heat insulation assembly;

[0044] The airborne liquid hydrogen storage tank includes a main body and a reinforcing member, the reinforcing member covering the main body;

[0045] The front clamp assembly is mounted on the irregularly shaped component of the reinforcing member on the front side of the airborne liquid hydrogen storage tank;

[0046] The rear clamp assembly is located on the rear side of the airborne liquid hydrogen storage tank;

[0047] The first thermal insulation component covers the main body of the airborne liquid hydrogen storage tank;

[0048] The second thermal insulation component is disposed between the front clamp component and the irregular component;

[0049] The third insulation component is disposed between the rear clamp component and the reinforcing area of ​​the reinforcing member, and the second and third insulation components divide the first insulation component into three parts.

[0050] The first insulation component has different performance characteristics from the second and third insulation components.

[0051] Furthermore, it also includes an adjustment and protection assembly disposed between the clamp assembly and the insulation assembly, wherein the adjustment and protection is a plurality of rubber strips.

[0052] Specifically, such as Figures 1-14 As shown, the axial direction of the storage tank is aligned with the aircraft's heading. The liquid hydrogen storage tank includes a main structure, comprising an inner tank 1 and reinforcing members. These reinforcing members cover the outer surface of the inner tank 1, providing uniform circumferential reinforcement to the main structure. The reinforcing members include a shaped component 2 and a reinforcing region 2'. The shaped component 2 is located on the front side of the main structure, and the reinforcing region 2' is located on the rear side. This region differs in thickness from other reinforcing members, being thicker than other regions. The shaped component is U-shaped or L-shaped, encircling the main structure. When U-shaped, the shaped component 2 includes a bottom edge and two vertical edges, located on either side of the bottom edge. The main structure utilizes a metal structure or a composite structure such as carbon fiber. Depending on the material selection and overload conditions, the inner tank and reinforcing member 2 are integrated using spot welding, brazing, or adhesive bonding. The reinforcing region 2' can be achieved by increasing the thickness of a corresponding area of ​​the main structure, or by using a thickened annular strip.

[0053] The insulation components include a first insulation component, a second insulation component, and a third insulation component. The first insulation component is low-density foam 3 disposed on the surface of the reinforcing member 2 throughout the main structure, such as... Figure 3As shown, the low-density foam 3, the reinforcing member 2, and the surface of the main structure are layered. The low-density foam 3 has good thermal insulation capabilities and is made of materials such as polyurethane closed-cell foam, which has a low thermal conductivity coefficient and effectively blocks heat transfer. The second insulation component is high-density foam 4, and the third insulation component is high-density foam 5. High-density foam 4 covers the irregularly shaped member 2, and high-density foam 5 covers the reinforcing area 2' on the rear side of the main structure. High-density foam 4 and 5 divide the low-density foam 3 into three areas, as shown. Figure 3 As shown, the insulation covers all surfaces of the main tank structure except for the second insulation zone formed by high-density foam 4 and the third insulation zone formed by high-density foam 5. High-density foams 4 and 5 are bonded to low-density foam 3 at the interface, ensuring that the main tank structure is fully covered by both densities of foam. In addition to their insulation capabilities, high-density foams 4 and 5 also possess strong strength properties, serving to transfer overload loads between the tank reinforcements and clamps while preventing direct heat transfer between them. Foams 3, 4, and 5 can be manufactured using spraying or bonding methods, followed by machining to completely cover the outer contour of the main tank structure.

[0054] Preferably, the front clamp assembly includes a lower front clamp 6 and an upper front clamp 8. The lower front clamp 6 includes a front side 61, a bottom surface 62, a rear side 63, a connecting plate 64, and a support plate 65, forming an integral structure. The outer end of the support plate 65 is connected to the lower skin of the fuselage, and the connecting plate 64 is connected to the upper front clamp 8 at corresponding positions by bolts or the like, thus connecting the lower front clamp 6 and the lower skin into one unit. Simultaneously, the front side 61, bottom surface 62, and rear side 63 all contact the high-density foam 4 through adhesive strips to transfer overload loads. The front upper clamp 8 includes a front side 81, a bottom surface 82, a rear side 83, a connecting plate 84, and a support plate 85, forming an integral structure. The outer end of the support plate 85 is connected to the skin of the machine body, and the connecting plate 84 is connected to the front lower clamp 6 at the corresponding position by bolts, so that the front upper clamp 8 and the upper skin are connected as one unit. At the same time, the front side 81, the bottom surface 82, and the rear surface 83 are all in contact with the high-density foam 4 through adhesive strips to transfer overload loads.

[0055] Preferably, the rear clamp assembly includes a lower rear clamp 7 and an upper rear clamp 9. The lower rear clamp 7 comprises a front side 71, a bottom surface 72, a rear side 73, a connecting plate 74, and a flange 75, forming an integral structure. The flange 75 is connected to the lower fuselage skin, and the connecting plate 74 is connected to the upper rear clamp 9 at corresponding positions via bolts, thus integrating the lower rear clamp 7 and the lower fuselage skin. Simultaneously, the bottom surface 72 contacts the high-density foam 5 via an adhesive strip to transfer overload loads. The upper rear clamp 9 comprises a front side 91, a bottom surface 92, a rear side 93, a connecting plate 94, and a flange 95, forming an integral structure. The flange 95 is connected to the lower fuselage skin, and the connecting plate 94 is connected to the lower rear clamp 7 at corresponding positions via bolts, thus integrating the upper rear clamp 9 and the upper fuselage skin. Simultaneously, the bottom surface 92 contacts the high-density foam 5 via an adhesive strip to transfer overload loads.

[0056] Preferably, the front clamp assembly can be fitted with a concave surface and high-density foam 4, such as... Figure 13 As shown.

[0057] Preferably, the rear clamp assembly can adopt a slotted or other structural form to further reduce the heat transfer path area between the machine body and the storage tank, and may include some cut features, such as... Figure 14 As shown.

[0058] Preferably, the connecting structure is further provided with an adjustment and protection component, which is implemented by a plurality of rubber strips 12, such as Figure 8 As shown, several rubber strips 12 include an upper front rubber strip 121, a lower front rubber strip 122, an upper rear rubber strip 123, and a lower rear rubber strip 124, which are respectively arranged in positions that cooperate with the upper front clamp, the lower front clamp, the upper rear clamp, and the lower rear clamp. These rubber strips are made of rubber material, which can adjust the gap between the foam 4 or 5 and the clamp on the one hand, and provide a certain degree of protection for the surface of the foam 4 or 5 on the other hand.

[0059] The directional overload of this utility model is transmitted through the setting of the irregular component 2. The use of this component allows the front clamp to block the storage tank. The vertical and lateral overload loads are transmitted through the side of the clamp and the vertical edge of the irregular component. The irregular component and the reinforcing area work simultaneously, and the load is transmitted through the contact between the bottom surface of the clamp and the reinforcing area.

[0060] By using contact to transfer loads, foams 3, 4, and 5 are used to separate the main structure from the aircraft's fuselage structure, avoiding direct connection between the main structure and the fuselage skin and other structures. This reduces heat transfer, minimizes heat leakage between the storage tank and the outside environment, and reduces liquid hydrogen evaporation.

[0061] As an embodiment of the present invention, the present invention also provides an aircraft, the aircraft including an airborne liquid hydrogen storage tank and the aforementioned connecting structure, the connecting structure fixing the airborne liquid hydrogen storage tank to the upper skin and lower skin of the aircraft.

[0062] Preferably, both the upper and lower skins are semi-cylindrical, and they are connected by overlapping. For example... Figure 6 and Figure 7 As shown, the upper skin 11 is semi-cylindrical and has an arched structure; the lower skin 10 is also semi-cylindrical and has a sunken structure. The cavity formed by the two is used to accommodate the airborne liquid hydrogen storage tank.

[0063] This utility model features an irregularly shaped component 2. After the storage tank is filled with liquid hydrogen at a low temperature of -253°C, it will shrink in the front-to-back direction. The clamp is connected to the fuselage skin (at a temperature close to room temperature). The rear reinforced area 2' slides through contact friction, thereby reducing the stress caused by the temperature difference.

[0064] like Figures 9-12 As shown, when using this connection structure to fix the airborne liquid hydrogen storage tank to the aircraft, the following operation process is included: First, the front lower clamp 6 and the rear lower clamp 7 are respectively assembled onto the lower skin 10, forming an integral structure using mechanical connection or adhesive bonding methods, such as... Figure 9 As shown;

[0065] Next, lower front rubber strips 122 and lower rear rubber strips 124 are placed on the front lower clamp 6 and rear lower clamp 7, respectively. Then, the liquid hydrogen storage tank is placed on the two rubber strips, where high-density foam 4 and high-density foam 5 mate with the lower front rubber strip 122 and lower rear rubber strip 124, respectively. The dimensions of the rubber strips are the same as those of the high-density foam. Figure 10 As shown.

[0066] Next, place the upper front adhesive strip 121 and upper rear adhesive strip 123 on top of high-density foam 4 and high-density foam 5. Then, place the upper clamps 8 and 9 in their corresponding positions, and finally connect the upper and lower clamps at the connecting plate using bolts, as shown. Figure 11 As shown.

[0067] Finally, the upper skin 11 is covered. The upper skin and the upper clamp are detachably or permanently connected by a flange. The upper skin and the lower skin are connected by an overlapping structure to form a detachable or permanent connection. Figure 12 As shown.

[0068] According to relevant standards, the structural design for emergency landing scenarios must ensure that, during a minor impact landing, each occupant has every reasonable chance to avoid serious injury under the following conditions, whereby the occupants are subjected to each of the following ultimate inertial load factors relative to the surrounding structure:

[0069] (i) Upwards, 3.0g;

[0070] (ii) Forward, 9.0g;

[0071] (iii) Lateral impact: 3.0g for the fuselage; 4.0g for the seat and its connectors;

[0072] (iv) Downward, 6.0g;

[0073] (v) Backwards, 1.5g.

[0074] As can be seen from the above requirements, the liquid hydrogen storage tank (containing liquid hydrogen) can transmit a maximum overload load of 9g in the heading direction, a maximum of 6g in the vertical direction, and a maximum of 4g in the lateral direction to the airframe structure. This places high demands on the connection structure between the liquid hydrogen storage tank and the airframe.

[0075] In this invention, the azimuth overload of the liquid hydrogen storage tank can be transferred to the high-density foam 4 via the vertical edge of the reinforcing member 2 surrounding its main structure, and then transferred to the front or rear side of the front clamp via the adhesive strip, ultimately reaching the fuselage skin. For vertical and lateral overloads, the liquid hydrogen storage tank transfers the load to the bottom surface of the front and rear clamps via the high-density foam 4 and 5, and then via the adhesive strip, ultimately reaching the fuselage skin as well.

[0076] The foregoing description illustrates and describes several preferred embodiments of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or related technical or knowledge. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be protected within the scope of the appended claims.

Claims

1. An attachment structure of an on-board liquid hydrogen storage tank to an aircraft body, characterized by, The structure includes: a front clamp assembly, a rear clamp assembly, and a heat insulation assembly; The airborne liquid hydrogen storage tank includes a main body and a reinforcing member, the reinforcing member covering the main body; The front clamp assembly is mounted on the irregularly shaped component of the reinforcing member on the front side of the airborne liquid hydrogen storage tank; The rear clamp assembly is located on the rear side of the airborne liquid hydrogen storage tank; The first thermal insulation component covers the main body of the airborne liquid hydrogen storage tank; The second thermal insulation component is disposed between the front clamp component and the irregular component; The third insulation component is disposed between the rear clamp component and the reinforcing area of ​​the reinforcing member, and the second and third insulation components divide the first insulation component into three parts. The first insulation component has different performance characteristics from the second and third insulation components.

2. The structure according to claim 1, characterized in that, The irregularly shaped component is U-shaped or L-shaped. When it is U-shaped, it includes a bottom edge and two vertical edges disposed on the bottom edge.

3. The structure according to claim 1 or 2, characterized in that, The front clamp assembly includes an upper front clamp and a lower front clamp.

4. The structure according to claim 1 or 2, characterized in that, The rear clamp assembly includes an upper rear clamp and a lower rear clamp.

5. The structure according to claim 3, characterized in that, Both the upper front clamp and the lower front clamp include a front side, a bottom surface, a rear side, a connecting plate, and a support plate. The front side and the rear side are located on both sides of the bottom surface. The connecting plate is located at both ends of the bottom surface, and a plurality of the support plates are located at the bottom end of the bottom surface.

6. The structure according to claim 4, characterized in that, Both the upper rear clamp and the lower rear clamp include a front side, a bottom surface, a rear side, a connecting plate, and a flange. The front side and the rear side are located on both sides of the bottom surface, the connecting plate is located at both ends of the bottom surface, and the flanges are located on the front side and the rear side respectively.

7. The structure according to claim 1, characterized in that, It also includes an adjustment and protection component disposed between the clamp assembly and the insulation assembly.

8. The structure according to claim 7, characterized in that, The adjustment and protection components consist of several rubber strips.

9. An aircraft, characterized in that, The aircraft includes an onboard liquid hydrogen storage tank and a connection structure as described in any one of claims 1-8, the connection structure fixing the onboard liquid hydrogen storage tank to the upper and lower skins of the aircraft.

10. The aircraft according to claim 9, characterized in that, Both the upper and lower skins are semi-cylindrical in shape and are connected by overlapping.

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