FUEL TANK OF OR FOR AN AIRCRAFT, AND AIRCRAFT WITH FUEL TANK

Abstract

A fuel tank of or for an aircraft. The fuel tank has an inner hull bordering a tank space to be filled with a fuel, and an outer hull encasing the inner hull with an insulation layer in-between, the insulation layer thus separating the outer hull from the inner hull. The fuel tank further has an internal reinforcement structure extending from the inner hull into the tank space, the reinforcement structure including at least one truss and may also include at least one anti-sloshing wall. Also an aircraft with such fuel tank.

Claims

1. A fuel tank of or for an aircraft, the fuel tank comprising: an inner hull bordering a tank space to be filled with a fuel; an outer hull encasing the inner hull; an insulation separating the outer hull from the inner hull, and a reinforcement structure extending from the inner hull into the tank space, the reinforcement structure comprising at least one truss.

2. The fuel tank according to claim 1, wherein the reinforcement structure comprises at least one anti-sloshing wall.

3. The fuel tank according to claim 1, wherein the at least one truss comprises at least one beam which is at least partially hollow.

4. The fuel tank according to claim 1, wherein the at least one truss comprises at least one triple of beams having longitudinal directions which span a three-dimensional space.

5. The fuel tank according to claim 1, wherein with regard to a designated orientation of the fuel tank in the aircraft, the reinforcement structure connects a ceiling of the inner hull with a bottom thereof, or a front portion of the inner hull with a rear portion thereof, or both.

6. The fuel tank according to claim 1, further comprising: a tank-side support system which is configured to support the fuel tank in a shell of the aircraft, wherein the reinforcement structure is connected to the inner hull at one or more connection points, or along one or more connection lines, or both respectively facing the tank-side support system with a respective gap, or energy absorption structure, or both in-between.

7. The fuel tank according to claim 1, wherein the fuel tank is configured as a pressure vessel for containing liquefied hydrogen.

8. An aircraft comprising: a shell; and, at least one fuel tank according to claim 1 supported in the shell.

9. The aircraft according to claim 8, wherein the outer hull of the at least one fuel tank has a tubular wall with opposite ends closed by respective domes, and, wherein the aircraft further comprises: a shell-side support system supporting the at least one fuel tank at a center region of at least one of the domes, or at an exterior region of at least one of the domes, or at several positions along the tubular wall of the outer hull, or at any combination thereof.

10. The aircraft according to claim 9, wherein the reinforcement structure is connected to the inner hull at one or more points, or along one or more lines, or both respectively facing the shell-side support system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In what follows, preferred embodiments of the present invention are explained with respect to the accompanying drawings. As is to be understood, the various elements and components are depicted as examples only, may be facultative and/or combined in a manner different than that depicted. Reference signs for related elements are to some extend used comprehensively and not necessarily defined again for each figure, and the same holds for evident analogies between the figures.

[0034] Shown are schematically in

[0035] FIG. 1 is a fuel tank according to a first exemplary embodiment of the present invention;

[0036] FIG. 2a is a fuel tank according to a second exemplary embodiment of the present invention in a sectional view;

[0037] FIG. 2b is a fuel tank according to a third exemplary embodiment of the present invention in a sectional view; and

[0038] FIG. 3 is an aircraft according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] FIG. 1 illustrates an exemplary embodiment of a fuel tank 100 according to the present invention in a perspective view. The fuel tank 100 may in particular be a hydrogen tank, i.e., a pressure vessel configured to contain liquefied hydrogen.

[0040] The fuel tank 100 comprises an inner hull 1 which borders a tank space S to be filled with the fuel (e.g., liquefied hydrogen), and an outer hull 2 encasing the inner hull 1. In the exemplary case shown, the inner hull 1 and outer hull 2 each comprise a respective tubular wall which in this case is cylindrically shaped and whose opposed ends are closed by respective domes.

[0041] An insulation layer 3 separates the inner hull 1 and the outer hull such that these do not contact each other. The insulation layer 3 may in particular be a vacuum insulation layer. Additionally or alternatively, the insulation layer may in particular include at least one foam insulation layer and/or at least one multi-layer insulation layer.

[0042] To provide an insight into the fuel tank and thereby demonstrate the present invention, the inner hull 1, the outer hull 2, and the insulation layer 3 are illustrated, in FIG. 1, as being transparent.

[0043] The fuel tank 100 further comprises a reinforcement structure 4 which extends from the inner hull 1 into the tank space S. The reinforcement structure 4 comprises a truss formed by a plurality of beams arranged in a tree-like manner in which some of the beams are connected to each other in respective nodes. For clarity reasons, only beams 10.sub.1, 10.sub.2, 10.sub.3, 10.sub.4, 10.sub.5, 10.sub.6, 10.sub.7 are referenced in FIG. 1.

[0044] In the exemplary embodiment shown in FIG. 1, the truss is three-dimensional. It in particular comprises various triples of beams whose longitudinal directions span a three-dimensional space. To provide for a clear arrangement, only the triple 10 formed by beams 10.sub.1, 10.sub.2, 10.sub.3 is referenced in FIG. 1. As apparent therefrom, with respect to the coordinate system indicated, beams 10.sub.1, 10.sub.2 together span a first plane which is parallel to the x-z-plane, and beams 10.sub.2, 10.sub.3 together span a second plane which is orthogonal to said first plane and parallel to the y-z-plane.

[0045] Moreover, the reinforcement structure 4, in particular the truss thereof connects a ceiling C of the inner hull 1 with a bottom B thereof. Thereby, a particularly high stability of the inner hull 1 can be achieved.

[0046] The reinforcement structure 4 in the inner space S of the fuel tank 100 illustrated in FIG. 1 further comprises a plurality of anti-sloshing walls 11.sub.1, 11.sub.2, 11.sub.3, 11.sub.4, 11.sub.5, 11.sub.6 which in the present case fill respective interspaces between associated beams of the truss. For instance, anti-sloshing wall 11.sub.1 fills an interspace between beams 10.sub.1, 10.sub.2, while anti-sloshing wall 11.sub.3 fills an interspace between beams 10.sub.3, 10.sub.2. In the present example, the anti-sloshing walls 11.sub.1, 11.sub.2, 11.sub.3, 11.sub.4, 11.sub.5, 11.sub.6 are further connected, along respective lines, to an inner surface of the inner hull 1.

[0047] By means of the truss and the anti-sloshing walls 11.sub.1, 11.sub.2, 11.sub.3, 11.sub.4, 11.sub.5, 11.sub.6, the reinforcement structure 4 combines the functionalities of increasing the stability of the inner hull 1 and reducing dynamic loading which results from the sloshing and acts on the fuel tank 100 itself and/or on a tank support structure (not shown in FIG. 1).

[0048] Moreover, in case of a potential crash of an aircraft (not shown) comprising the fuel tank 100, the reinforcement structure 4 provides advantageous crash load paths in particular if the fuel tank is supported, in a shell of the aircraft, by way of a continuous support concept (not shown in FIG. 1).

[0049] FIG. 2a illustrates such continuous support concept implemented for a fuel tank 100 according to a further exemplary embodiment of the present invention. Similar to the fuel tank 100 illustrated in FIG. 1 and described above, the fuel tank 100 comprises an inner hull 1, an outer hull 2, and an insulation layer 3 separating the inner hull 1 from the outer hull 2. Therein, the outer hull 2 of the fuel tank 100 comprises a cylindrically shaped tubular wall 2.sub.1 whose opposite open ends are closed by respective domes 2.sub.2, 2.sub.3, and the inner hull 1 is shaped analogously.

[0050] The fuel tank 100 further comprises a reinforcement structure 4 extending from the inner hull 1 into a tank space S of the fuel tank 100, the reinforcement structure 4 comprising a truss and connecting a bottom B of the inner hull 1 with a ceiling C thereof.

[0051] Analogously to the embodiment shown in FIG. 1, the reinforcement structure 4 may preferably further comprise at least one anti-sloshing wall (not visible in FIG. 2a).

[0052] A tank-side support system 5 of the fuel tank 100 comprises a strut system with various struts which are attached to and/or integrated in the outer hull 2 at respective points along a length of the tubular wall 2.sub.1 of the outer hull 2 and which are respectively supported by a shell-side support system 201. Therein, towards the inner hull 1, the struts of the support system 5 face, with a respective gap g in-between, respective connection point/s (or even connection lines running in a direction orthogonal to an image plane, thus not visible in FIG. 2a) at which the reinforcement structure 4 is connected, with respective ends of beams 10.sub.1, 10.sub.2, 10.sub.3, 10.sub.4 of its truss, to the inner hull 1.

[0053] In combination with the shell-side support system 201 and the tank-side support system 5, the reinforcement structure 4 thereby provides particularly advantageous load paths in a potential crash scenario. These load paths become active only in case of a sufficient deformation of the outer hull 2 and/or of the inner hull 1 causing the gaps g to be closed. Moreover, they run through the tank space S and thereby provide a particularly efficient load transfer in addition to conventional load transfers running, along the outer hull, around the tank space.

[0054] FIG. 2b shows, in a view similar to that of FIG. 2a, a fuel tank 100 according to a further embodiment of the present invention. The fuel tank 100 comprises an inner hull 1, an outer hull 2, and an insulation layer 3 separating the inner hull 1 from the outer hull 2. Therein, the outer hull 2 of the fuel tank 100 comprises a cylindrically shaped tubular wall 2.sub.1 whose opposite open ends are closed by respective domes 2.sub.2, 2.sub.3, and the inner hull 1 is shaped analogously.

[0055] The fuel tank 100 further comprises a reinforcement structure 4 extending from the inner hull 1 into a tank space S of the fuel tank 100, comprising a truss, and in this embodiment connecting a front portion F of the inner hull 1 with a rear portion R thereof; as is to be understood, the front portion and the rear portion are defined with respect to a devised installation of the fuel tank 100 in an aircraft and a designated direction of flight thereof.

[0056] Analogously to the embodiment shown in FIG. 1, the reinforcement structure 4 may preferably further comprise at least one anti-sloshing wall (not visible in FIG. 2b).

[0057] As further illustrated in FIG. 2b, the fuel tank 100 comprises a tank-side support system 5 which in this case comprises as a strut system 5.sub.1 and mount elements 5.sub.2.

[0058] The strut system 5.sub.1 comprises various struts which are attached to and/or integrated in the outer hull 2 at respective points along a length of the tubular wall 2.sub.1 of the outer hull 2. Therein, the struts are respectively supported by first components of a shell-side support system 201. Towards the inner hull 1, the struts of the strut system 5.sub.1 face, with respective gaps g in-between, respective connection point/s (or even connection lines running in a direction orthogonal to an image plane, thus not visible in FIG. 2b) at which the reinforcement structure 4 is connected to the inner hull 1.

[0059] The mount elements 5.sub.2 each are attached to a respective one of the domes 2.sub.2, 2.sub.3 of the outer hull 2, and they are respectively supported by second components of the shell-side support system 201. Towards the inner hull 1, the mount elements 5.sub.2 face, with a respective gap G in-between, respective connection points at which the reinforcement structure 4 (namely, beams 10.sub.1, 10.sub.2 of its truss) is connected to the inner hull 1.

[0060] Accordingly, a combination of both a continuous support concept and a polar support concept is implemented by the fuel tank 100 shown in FIG. 2b.

[0061] Analogous to the case of the fuel tank 100 shown in FIG. 2a, the load paths provided by the reinforcement structure 4 in combination with the shell-side support system 201 and the tank-side support system 5 shown in FIG. 2b become active only in case of a sufficient deformation of the outer hull 2 respectively causing the gaps g, G to be closed.

[0062] FIG. 3 illustrates an aircraft 1000 according to an embodiment of the present invention with its designated direction D of flight. The aircraft 1000 comprises a shell 200 and, installed therein, a fuel tank 100 according to an embodiment of the present invention. As indicated in FIG. 3, the fuel tank 100 comprises an inner hull 1, an outer hull 2 encasing the inner hull 1 and separated therefrom by an insulation layer 3, and a reinforcement structure 4 which extends from the inner hull 1 into the tank space and which comprises at least one truss and at least one anti-sloshing wall. The fuel tank 100 may be supported, within the shell 200, by implementing a continuous support concept, a polar support concept and/or a dome support concept (not shown in FIG. 3).

[0063] Disclosed is a fuel tank 100, 100, 100, 100 of or for an aircraft 1000. The fuel tank comprises an inner hull 1, 1, 1, 1 bordering a tank space S to be filled with a fuel, and an outer hull 2, 2, 2, 2 encasing the inner hull 1, 1, 1, 1 with an insulation layer 3, 3, 3, 3 in-between, the insulation layer thus separating the outer hull 2, 2, 2, 2 from the inner hull 1, 1, 1, 1. The fuel tank further comprises an internal reinforcement structure 4, 4, 4, 4 extending from the inner hull into the tank space S, the reinforcement structure comprising at least one truss. The reinforcement structure may in particular further comprise at least one anti-sloshing wall 11.sub.1, 11.sub.2, 11.sub.3, 11.sub.4, 11.sub.5, 11.sub.6.

[0064] Further disclosed is an aircraft 1000 comprising such fuel tank 100, 100, 100, 100.

[0065] While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms comprise or comprising do not exclude other elements or steps, the terms a or one do not exclude a plural number, and the term or means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.

REFERENCE SIGNS

[0066] 1, 1, 1, 1 inner hull [0067] 2, 2, 2, 2 outer hull [0068] 2.sub.1, 2.sub.1 tubular wall of outer hull [0069] 2.sub.2, 2.sub.3, 2.sub.2, 2.sub.3 dome of outer hull [0070] 3, 3, 3, 3 insulation layer [0071] 4, 4, 4, 4 reinforcement structure [0072] 5, 5 tank-side support system: [0073] 5.sub.1 strut system of tank-side support system 5 [0074] 5.sub.2 mount element of tank-side support system 5 [0075] 10.sub.1, 10.sub.2, 10.sub.3, 10.sub.4, 10.sub.5, 10.sub.6, 10.sub.7 beam [0076] 10.sub.T triple of beams spanning three-dimensional space [0077] 10.sub.1, 10.sub.2, 10.sub.3, 10.sub.4 beam [0078] 10.sub.1, 10.sub.2 beam [0079] 11.sub.1, 11.sub.2, 11.sub.3, 11.sub.4, 11.sub.5, 11.sub.6 anti-sloshing wall [0080] 100, 100, 100, 100 fuel tank [0081] 200 shell [0082] 201, 201 shell-side support system [0083] 1000 aircraft [0084] B bottom of inner hull [0085] C ceiling of inner hull [0086] designated direction of flight D [0087] F front portion of inner hull [0088] g gap [0089] G gap [0090] R rear portion of inner hull [0091] S tank space