CRYOTANK

Description

Field of the invention

[0001] The present invention relates to a cryogenic tank comprising an inner container for holding a cryogenic medium, in particular hydrogen, and an outer container surrounding the inner container. State of the art

[0002] Cryogenic tanks are known per se and are used for storing cryogenic liquids, particularly liquid hydrogen. This medium can be used, in particular, as fuel for a moving or flying means of transport, for example, a motor vehicle, aircraft, or space rocket. Cryogenic tanks typically comprise an inner container containing the medium stored in the tank, particularly the hydrogen, and an outer container surrounding the inner container. A vacuum is typically created between the inner and outer containers to reduce heat transfer from the outside to the inside. Such cryogenic tanks can be cylindrical.

[0003] The required functional components of such a cryogenic tank, such as valves, control components, and pipes, are arranged, for example, at the front of the cryogenic tank, outside the outer vessel or in the vacuum space between the outer vessel and the inner vessel. When the functional components are arranged at the front, it is usually necessary to shorten the axial length of the cryogenic tank, or at least of the inner vessel, so that less volume is available for storing the medium.

[0004] WO 2021 / 052994 A2 discloses a cryogenic pressure vessel for storing fuel in a motor vehicle, comprising an inner vessel and an outer vessel, wherein an evacuated space is arranged at least partially between the inner vessel and the outer vessel. At least one electric heating element for heating the fuel can be provided in the inner vessel.

[0005] US 8 104 296 B2 discloses a cryogenic storage tank comprising a cryogenic space defined by a thermally insulated container for storing a cryogenic fluid; a partition wall dividing the cryogenic space into a main storage space and an auxiliary space; a conduit connecting the main storage space to a coupling external to the storage tank; a valve disposed within the cryogenic space and connected to a first fluid passage through the partition wall, the valve comprising a valve element operable by fluid forces within the cryogenic space to move between an open position and a closed position;and a second fluid passage through the partition, the second fluid passage comprising a restricted flow area dimensioned to have a cross-sectional flow area smaller than that of the conduit such that there is a detectable increase in backpressure in the conduit when the cryogenic fluid is introduced into the main storage space and the main storage space is filled with liquefied gas;

[0006] Document US 2005 / 139600 A1 teaches a container for containing a cryogenic fluid, the container comprising: an inner vessel defining a cryogenic space and having a horizontal, elongated axis; an outer vessel surrounding the inner vessel and forming an evacuable space between the outer vessel and the inner vessel; and a structure for supporting the inner container within the outer container, the structure comprising: a conduit attached at a first point to a support for the inner container connected to the inner container and at a second point to a support for the outer container, the conduit being capable of supporting a substantial portion of the axial loads acting on the inner container in a direction parallel to the horizontal axis, and wherein the cryogenic fluid can be conveyed into and / or out of the cryogenic space through the conduit;and at least one non-metallic support extending between the inner container and the outer container, the non-metallic support providing a bearing surface connected to respective opposing surfaces associated with the inner container and the outer container for transferring substantially all radial loads transverse to the horizontal axis from the inner container to the outer container, and the non-metallic support being fixedly attached to the opposing, facing surfaces, whereby the non-metallic support can carry a substantial portion of the axial loads.; Summary of the invention

[0007] It is an object of the invention to provide a cryogenic tank which has the largest possible internal container volume in a given installation space despite the installation of functional components.

[0008] The problem is solved by a cryogenic tank having the features according to claim 1.

[0009] The cryogenic tank comprises an inner container for containing a cryogenic medium, in particular hydrogen, and an outer container surrounding the inner container. A vacuum space is provided between the inner container and the outer container. A pocket extends at least from the vacuum space into the interior of the inner container. One or more functional components, such as one or more heat exchangers, valves, control components, and / or pipes, are arranged in the pocket. According to the invention, a cryogenic tank thus has at least one pocket, i.e., a pocket-like depression or indentation, with a bottom at the end of the pocket, i.e., within the usual volume of the inner container.The pocket therefore extends from outside the inner container, i.e. at least from the vacuum space, optionally also from the outer container or from outside the outer container, into the usual geometry of the inner container in order to delimit a volume that usually belongs to the interior of the inner container and, as part of the interior of the pocket, to topologically make it an exterior space of the inner container. The interior of the pocket is accessible from outside the inner container, preferably from the vacuum space. The diameter of the pocket is smaller than the diameter of the inner container at the point where the pocket extends into the inner container. This means that less volume of the inner container is lost than if the entire inner container were shortened across its entire diameter.

[0010] Functional components are arranged in the pocket. These functional components can, in particular, be secondary system components. The functional components can thus also be arranged within the usual interior space of the inner container, where they are separated and protected from the medium in the inner container by the confining wall of the pocket.

[0011] The displaced volume of a pocket extending into the inner container to accommodate the required components is smaller than if the length of the entire cylinder of the inner container were reduced.

[0012] According to the invention, at least four pipes lead from outside the pocket to a functional component arranged in the pocket, namely to a heat exchanger arranged in the pocket. At least one pipe is configured for supplying and one pipe is configured for discharging the cryogenic medium contained in the inner container, and at least one pipe is configured for supplying and one pipe is configured for discharging a temperature control fluid. The heat exchanger thus serves to control the temperature of the cryogenic medium, in particular hydrogen, contained in the inner container. This medium is guided from an area outside the pocket, and preferably from an area outside the inner container, into the pocket to be temperature-controlled there.

[0013] Further developments of the invention are specified in the dependent claims, the description and the accompanying drawings.

[0014] Preferably, the pocket is formed, at least in sections, by a sheath tube that extends into the interior of the inner container. Preferably, the pocket is cylindrical, at least in sections. The pocket is closed at its end, thus preferably having a bottom at the end of the cylinder.

[0015] Preferably, the pocket is closed by a lid, in particular toward the vacuum chamber or outside the outer container. The lid is preferably a separate component.

[0016] Preferably, the cryogenic medium, in particular hydrogen, held in the inner container is supplied to a functional component in the bag through a pipeline from outside the inner container, from the vacuum space or from the space outside the outer container through the lid of the bag.

[0017] Preferably, all pipes leading from outside the pocket to a functional component arranged in the pocket are led through an opening in the lid of the pocket, preferably through an opening in the lid of the pocket assigned to the respective pipe.

[0018] Preferably, the pocket is aligned parallel to the longitudinal center axis of the cryotank or normal to the longitudinal center axis of the cryotank.

[0019] Preferably, the pocket extends inwards from a front end cap of the inner container, or from a lateral surface of the inner container, preferably in the direction of a center point of the inner container.

[0020] The pocket is particularly preferably arranged coaxially to the longitudinal center axis of the cryotank.

[0021] Particularly preferably, the pocket extends to the outer container. The pocket can be configured to suspend the inner container from the outer container. The pocket can form a polar suspension of the inner container from the outer container.

[0022] Preferably, at least one functional component is arranged in the pocket such that the functional component runs essentially parallel to a side wall of the pocket. In particular, at least one, preferably cylindrical or rod-shaped, heat exchanger and / or at least one tube can run parallel to the pocket or parallel to the side walls of the pocket.

[0023] The bag preferably has thermal insulation to protect the functional components arranged in the bag, in particular multi-layer insulation (MLI). Brief description of the drawings

[0024] The invention is described below by way of example with reference to the drawings. Fig. 1 is an exploded view of a front section of a cryogenic tank according to the invention, shown without an outer container. Fig. 2 is a view of the cryogenic tank according to Fig. 1 from the front. Fig. 3 is a sectional view of the cryotank according to section AA of the Fig. 2 , shown with outer container. Detailed description of the invention

[0025] In the Fig. 1-3 a cryogenic tank according to the invention is shown.

[0026] The cryogenic tank comprises an inner container 1 for holding a cryogenic medium, in particular hydrogen, and an outer container 2 surrounding the inner container 1, wherein a vacuum space 3 is arranged between the inner container 1 and the outer container 2. A container insulation 11 is also applied to the outside of the inner container 1 (shown in Fig. 3 ).

[0027] The inner container 1 comprises a shell surface 1.1 of the inner container 1 and a front end cap 1.2 of the inner container 1.

[0028] A pocket 4 extends from the vacuum space 3 into the interior of the inner container 1, thus forming an indentation in the volume normally enclosed by the inner container 1, which in the example shown essentially forms a cylinder with convex end faces.

[0029] At least one functional component 5, namely a heat exchanger 6, is arranged in the pocket 4. The heat exchanger 6 is arranged within a spatial region that is typically located in the interior of the inner container, but is separated from the medium in the interior by the pocket 4. The pocket 4 is essentially cylindrical. The diameter of the pocket 4 is smaller than the diameter of the inner container 1, preferably less than half the diameter of the inner container 1.

[0030] The pocket 4 is formed in sections by a cylindrical sleeve, namely the cladding tube 8, which extends into the interior of the inner container 1. The cladding tube 8 has a base, which can be a separate component or formed integrally with the cladding tube 8.

[0031] The pocket 4 is closed by a lid 9 towards the vacuum chamber 3.

[0032] The pocket 4 is aligned parallel to the longitudinal center axis of the cryogenic tank, namely coaxially to the longitudinal center axis of the cryogenic tank. The pocket 4 extends inward from a front end cap 1.2 of the inner container 1, toward a center point of the inner container 1.

[0033] The cryogenic medium, in particular hydrogen, held in the inner container 1 is supplied to the heat exchanger 6 in the pocket 4 through a pipe 10 from outside the inner container 1, namely through the pipe 10 in the vacuum chamber 3 and through an opening in the lid 9 of the pocket 4.

[0034] Another pipe 10 serves to drain the cryogenic medium contained in the inner container 1. Additionally, two pipes 10 are provided from outside the pocket 4 for supplying and discharging a temperature control fluid or cooling medium.

[0035] All pipes 10 are guided through openings in the cover 9 of the pocket 4 assigned to the respective pipe 10.

[0036] The pocket 4, in particular the cladding tube 8, has thermal insulation to protect the functional components 5 arranged in the pocket 4, in particular the heat exchanger 6, in particular a multi-layer insulation (MLI). List of reference symbols

[0037] 1Inner vessel 1.1Shell surface of the inner vessel 1.2End cap of the inner vessel 2Outer vessel 3Vacuum chamber 4Pocket 5Functional component 6Heat exchanger 7Tube 8Cover tube 9Cover 10Pipeline 11Vessel insulation

Claims

1. Cryogenic tank comprising an inner container (1) for holding a cryogenic medium, in particular hydrogen, and an outer container (2) surrounding the inner container (1), wherein a vacuum space (3) is set up between the inner container (1) and the outer container (2), wherein a pocket (4) extends at least from the vacuum space (3) into the interior space of the inner container (1), wherein one or more functional components (5) are arranged in the pocket (4), such as one or more heat exchangers (6), valves, control components and / or tubes (7), characterized in that at least four pipes (10) lead from outside the pocket (4) to a functional component (5) arranged in the pocket (4), namely to a heat exchanger (6) arranged in the pocket (4), wherein at least one pipe (10) is set up for the supply and one pipe (10) is set up for the discharge of the cryogenic medium held in the inner container (1) and at least one pipe (10) is set up for the supply and one pipe (10) is set up for the discharge of a temperature control fluid.

2. Cryogenic tank according to Claim 1, characterized in that the pocket (4) is formed at least in some section or sections by a jacket tube (8) which extends into the interior space of the inner container (1) and / or in that the pocket (4) is cylindrical at least in some section or sections.

3. Cryogenic tank according to at least one of the preceding claims, characterized in that the pocket (4) is closed by a cover (9).

4. Cryogenic tank according to at least one of the preceding claims, characterized in that the cryogenic medium, in particular hydrogen, held in the inner container (1) is supplied to a functional component (5) in the pocket (4) through a pipe (10) from the outside of the inner container (1), namely from the vacuum space (3) or from the space outside the outer container (2)through the cover (9) of the pocket.

5. Cryogenic tank according to Claim 4, characterized in that all the pipes (10), which lead from outside the pocket (4) to a functional component (5) arranged in the pocket (4), iare passed through an opening in the cover (9) of the pocket (4), preferably being passed through an opening, assigned to the respective pipe (10), in the cover (9) of the pocket (4).

6. Cryogenic tank according to at least one of the preceding claims, characterized in that the pocket (4) is aligned parallel to the longitudinal central axis of the cryogenic tank or is aligned so as to be normal to the longitudinal central axis of the cryogenic tank.

7. Cryogenic tank according to Claim6, characterized in that the pocket (4) is arranged coaxially with the longitudinal central axis of the cryogenic tank.

8. Cryogenic tank according to at least one of the preceding claims, characterized in that the pocket (4) extends as far as the outer container (2), and / or in that the pocket (4) is designed for suspension of the inner container (1) on the outer container (2)9. Cryogenic tank according to at least one of the preceding claims, characterized in that the pocket (4) extends inwards from an end cap (1.2) at the end of the inner container (1) or from a lateral surface (1.1) of the inner container (1), preferably in the direction of a central point of the inner container (1).

10. Cryogenic tank according to at least one of the preceding claims, characterized in that at least one functional component (5) is arranged in the pocket (4) in such a way that the functional component (5) lies substantially parallel to a side wall of the pocket (4), in particular at least one substantially cylindrical heat exchanger (6) and / or at least one tube (7).

11. Cryogenic tank according to at least one of the preceding claims, characterized in that the pocket (4) has thermal insulation for protecting the functional components (5) arranged in the pocket (4), in particular multi-layer insulation (MLI).