Disassemblable liquid gas storage device

Description

[0001] The present invention relates to the fields of aeronautics, rail, road or maritime.

[0002] From its beginnings, aviation used high-octane gasoline engines. After 1945, the development of the jet engine and turbine led to the use of kerosene, which has a higher molecular mass than gasoline and is less flammable. These fuels are stored in tanks located in the wings, the wing-fuselage junction, or the tail.

[0003] The trend toward reducing carbon dioxide emissions has led to more fuel-efficient engines. However, the gains in carbon dioxide emissions are diminishing as certain technologies mature, particularly the tip speed of the turbine blades. Introducing a radical change has become increasingly desirable.

[0004] This led to the development of gas-powered aircraft projects. The combustion of short-chain or non-existent carbon gases, sometimes with oxygen, produces little or no pollution. However, storing H2, O2, or C1 or C2 gases is difficult and prone to leaks due to the small size of the gas molecules.

[0005] On the ground, the storage of such gases is generally carried out in pressure vessels that are too heavy, too bulky, and contain too much pressure potential energy to be carried on board an aircraft, or in welded and / or glued cryogenic tanks. The cryogenic storage of such gases is limited to a duration proportional to the volume stored.

[0006] US10955089 B2 discloses a cryogenic tank.

[0007] Furthermore, hydrogen, methane, ethane, ethylene, acetylene, or oxygen stored in liquid form cannot be used by an internal or external combustion engine or a fuel cell. Final consumption requires a gaseous state.

[0008] The need arose to store propellant gas within an aircraft for onboard use, while utilizing existing aeronautical maintenance expertise and avoiding the need for new standards. Indeed, developing new standards is a lengthy and time-consuming process, which could lead to delays in the commercialization of gas-powered aircraft. Acquiring new maintenance expertise is also a lengthy and costly process, and may even encounter resistance.

[0009] The invention proposes an onboard aeronautical cryogenic gas storage tank device, spherical or elongated in shape, comprising an inner container defining a liquefied gas storage chamber, an outer casing containing the inner container and made of several removable parts allowing access to the inner container, the outer casing being made of a material resistant to temperatures from less than -60°C to at least +80°C, an isolation chamber defined between the inner container and the outer casing, the reduced pressure isolation chamber having a helium tightness equal to or better than 10⁻⁹ millibar*liter / second defined between the inner container and the outer casing, two connections, at least one of which is a sliding connection, supporting the inner container and carried by the outer casing, a removable collector passing through the outer casing and the inner container in a leak-proof manner,and a flexible, thermally insulating neck forming a sealed interface between the collector on one side and the outer casing and inner container on the other. The neck is formed around a portion of the collector. The neck passes through the insulation chamber to allow the collector to be removed independently of the pressure within the insulation chamber. Thanks to the invention, the cryogenic tank meets the requirements, particularly thermal requirements, of aeronautical practices, especially in terms of mechanical deformation, and the space constraints of the piping.

[0010] In one embodiment, the device includes a thermally insulating plug assembly removably mounted to the collector and accessible from the outside. The thermal insulation is satisfactory.

[0011] In one embodiment, one of the connections includes an axial concavity in the outer casing that receives and supports an axial projection of the inner container. The connection is adapted to accommodate potential expansions.

[0012] In one embodiment, the outer casing comprises a frame, watertight panels, and pressure-resistant seals between the frame and the panels and / or between the panels. Maintenance is facilitated.

[0013] In one embodiment, the chassis comprises members and longitudinal members. The construction is robust.

[0014] In one embodiment, the sealing gaskets are housed in grooves and, in their free state, protrude from the grooves by a height less than 10% of the height of said sealing gaskets. The sealing is of a high standard.

[0015] In one embodiment, the device includes an anti-sway element inside the inner container. The mechanical behavior, particularly the stability, of the device is improved.

[0016] In one embodiment, the device includes a stiffener inside the inner container, preferably a spacer or a tie rod. The device, particularly the inner container, can be lightened.

[0017] In one embodiment, the device includes at least one support ring mounted between the inner container and the outer casing, away from the connections within the insulation chamber. This increases rigidity.

[0018] In one embodiment, a hydrogen-adsorbing material is placed in the isolation chamber. A low pressure is maintained in the isolation chamber.

[0019] In one embodiment, a hydrogen presence detector is installed in the isolation chamber. An alarm may be triggered if a limit value is exceeded.

[0020] In one embodiment, an assembly comprises a device as above, a temporary storage tank forming a gasification element for pressurizing the gas supplied by the device, an upstream valve intended to be open for liquid flow during a filling phase of the temporary storage tank and closed outside of the filling phase, a downstream valve intended to be open for gas flow during an emptying phase of the temporary storage tank and closed outside of the emptying phase, the upstream and downstream valves being closed during a gasification phase, the upstream and downstream valves being on / off controlled, and a compressor disposed downstream of the downstream valve, said compressor being active at the end of the emptying phase to bring the pressure in the temporary storage tank to a value lower than the pressure value in the device,and a pressure regulator located downstream of the downstream valve, said regulator being active at the beginning of the emptying phase to reduce the outlet gas pressure to a value lower than the pressure in the temporary storage tank. The system ensures the aircraft, through the volume contained in the temporary tank(s), the necessary autonomy regardless of the system's condition. The temporary tanks can be designed for a gas pressure of several hundred bar.A chosen gas pressure is nevertheless supplied to the consuming components. The valves are reliable. The temporary tank can be emptied sufficiently to increase the amount of gas available to the consuming components and bring the temporary tank to a final pressure lower than the current pressure in the system. The temporary tank is filled by operating a cryogenic valve under the effect of the pressure difference. Eliminating the need for a cryogenic pump results in weight savings and a reduction in the risk of incidents.

[0021] In one embodiment, the temporary storage tank is designed for a working pressure greater than 500 bar.

[0022] In one embodiment, the device is designed for a working pressure of less than 8 bars.

[0023] Other features and advantages of the invention will become apparent upon examination of the detailed description below, and the accompanying drawings, in which: [Fig.1] illustrates schematically in axial section a device according to one aspect of the invention. [Fig.2] illustrates schematically in cross-section a device according to one aspect of the invention. Fig.3 [ ] schematically illustrates, in side view, a disassembled device according to one aspect of the invention. ] Fig.4 ] schematically illustrates, in side view, a disassembled device according to another aspect of the invention. Fig.5 [ ] schematically illustrates in perspective a device according to another aspect of the invention. ] Fig.6 [ ] schematically illustrates in cross-section a neck according to one aspect of the invention. ] Fig.7 [ ] schematically illustrates in cross-section a neck and a collector according to one aspect of the invention. ] Fig.8 ] illustrates schematically in perspective an assembly according to an aspect of the invention.

[0024] The attached drawings may not only serve to complement the invention, but also contribute to its definition, if necessary.

[0025] The aeronautical gas storage system is designed to be carried by an aircraft: airplane, drone, helicopter, etc. The aeronautical gas storage system contains liquid and supplies gas. In other words, the gas is stored at very low temperatures in liquid form within a cryogenic tank. A cryogenic tank is not designed to withstand high pressures, particularly those exceeding 10 bar.

[0026] The stored gas is chosen from hydrogen, methane, ethane, ethylene, acetylene and oxygen.

[0027] The Applicant also intends to take into account that gasification is a rapid phenomenon even in an ambient atmosphere of -55°C found at high altitudes. As an embodiment, gaseous hydrogen at 0°C and 1 atmosphere has a density approximately 800 times lower than liquid hydrogen at -253°C, and therefore a volume approximately 800 times greater.

[0028] However, aircraft maintenance regulations require the ability to disassemble and repair or replace most aircraft parts. Thus, an aircraft is capable of landing at any location—an airfield for a plane, a landing area for a helicopter—suited to its weight and landing requirements, but not equipped with maintenance facilities specific to the aircraft model. In the event of a detected fault, the aircraft is configured to be repaired, either permanently or temporarily, or disassembled to replace or repair a defective component, in accordance with the manufacturer's manuals and documents approved by the aviation safety authorities. Ideally, the component should be easily accessible to a maintenance technician. If a replacement is necessary, the component should be as small as possible for easy handling and transport.In the event of repair, it is desirable that the component be repairable using tools and processes that are proven and common in the aeronautical field.

[0029] An aircraft is subject to daily, weekly, etc. inspection visits, immobilizing the aircraft for a period of time inversely proportional to the frequency.

[0030] However, gas tanks in the terrestrial industrial or space domain are not subject to such requirements, in particular they are not designed for such repairability.

[0031] The Applicant has identified a need for storage, in particular of hydrogen, methane, ethane, ethylene, acetylene or oxygen, from aeronautical cryogenic tanks carried by the aircraft.

[0032] The Applicant has identified a need for demountable, inspectable, and repairable aeronautical cryogenic tanks. Furthermore, they are seeking a tank with a high usable volume / external volume ratio, a high gas mass / total mass ratio, and high reliability and safety.

[0033] As illustrated in the figures, the aeronautical gas storage device has a generally elongated shape with rounded ends. The aeronautical gas storage device can be annular around a longitudinal axis. The aeronautical gas storage device comprises an outer casing and an inner container. The inner container forms a storage chamber for the liquid gas. The inner container is contained within the outer casing. Generally, the inner container and the outer casing are separated from each other.

[0034] In the embodiment shown, the aeronautical gas storage device has a cylindrical central section of revolution and hemispherical ends. However, shapes exhibiting exceptions to cylindricity, annularity, and / or hemisphericity may be manufactured.

[0035] Each cryogenic tank is insulated to contain liquid fuel or oxidizer at -253°C. Each cryogenic tank is capable of withstanding a maximum working pressure of approximately 6 to 10 bar.

[0036] In the embodiment illustrated on the figures 1 à 3 Cryogenic tank 2 has an elongated shape, particularly around an axis. It features domed ends and a generally cylindrical central section. Alternatively, cryogenic tank 2 may have a spherical shape.

[0037] The cryogenic tank 2 comprises an inner container 26 and an outer casing 27. The inner container 26 defines a storage chamber 28 for liquefied gas, containing a gas charge at its liquefaction temperature and a headspace for evaporated gas. The inner container 26 is leak-proof. The inner container 26 is capable of withstanding a liquefaction temperature, for example, -253°C for hydrogen. The outer casing 27 contains the inner container 26. The outer casing 27 is made of several removable parts allowing access to the inner container 26. The outer casing 27 protects the inner container 26 against impacts. The outer casing 27 ensures the structural integrity of the aeronautical gas storage device. The outer casing 27 is made of a material resistant to temperatures from below -60°C to at least +80°C.

[0038] Between the inner container 26 and the outer casing 27, an isolation chamber 29 is defined. Insulation in the isolation chamber 29 is ensured by a pressure reduced relative to atmospheric pressure. In addition, a solid insulating material may be placed in the isolation chamber 29. The reduced-pressure isolation chamber 29 has a helium leak-tightness equal to or better than 10⁻⁹ millibars per second, defined between the inner container 26 and the outer casing 27. The leak-tightness of the isolation chamber 29 encompasses both leak-tightness with respect to the interior of the inner container 26 and leak-tightness with respect to the external atmosphere.

[0039] The inner container 26 can be made of welded metal alloy. Examples of metal alloys include Al-Cu-Li, particularly 2050 or 2099; Al-Cu, particularly 2219; and stainless steel, particularly 304, 304L, 316, and 316L. The inner container 26 has an elongated shape with two convex ends surrounding a body. The body can be cylindrical or of revolution.

[0040] The outer casing 27 comprises a frame 30, sealed panels 31, pressure-resistant sealing joints between the frame 30 and the panels 31 and / or between the panels 31. The panels 31 can be assembled to the frame 30 by screwing.

[0041] The frame 30 comprises members 32 and longitudinal members 33. The members 32 may have a closed contour, for example, an annular shape. The longitudinal members 33 extend longitudinally. The longitudinal members 33 meet at the ends of the outer shell 27.

[0042] The 31 panels are made of welded metal alloy or composite materials. Examples of composite materials include epoxy resin with carbon fibers, Kevlar fibers, and / or glass fibers. Examples of metal alloys include Al-Mg (particularly 5086), Al-Mg-Si (particularly 6061), and Al-Cu-Li (particularly 2195).

[0043] Seals are provided between the panels 31 and the frame 30. These seals can be metal-on-metal or made of a synthetic material, for example, elastomer. In the case of synthetic seals, grooves are formed in the panels 31 or in the frame 30 to accommodate them. When unsupported, the seals protrude from the grooves by a height less than 10% of the seal's height. The height refers to the diameter of an O-ring.

[0044] The cryogenic tank 2 includes two links between the outer shell 27 and the inner container 26 to support the inner container 26. The links are configured for very low thermal conduction.

[0045] At least one of the joints is a sliding joint designed to accommodate the differential expansion of the outer shell 27 and the inner container 26. The joints are supported by the outer shell 27. One of the joints is an extreme joint. The extreme joint 34 may include a central projection at one end of the inner container 26 that cooperates with an axial concavity of the outer shell 27, forming a housing for the protrusion. This protrusion allows axial sliding over a stroke of a few millimeters, such that the contraction of the inner container 26 during filling with liquefied gas and its expansion after emptying the liquefied gas are unrestricted. The extreme joint 34 is configured to provide a long thermal conduction path.

[0046] The second bond is located at a distance from the opposite end to the first bond. The second bond surrounds the inner container 26. The second bond is mounted in the insulation chamber 29. The second bond includes a support ring 35. The support ring 35 is mounted between the inner container 26 and the outer casing 27. The support ring 35 is mounted at a distance from the bonds in the insulation chamber 29.

[0047] The support ring 35 includes external sectors 36 projecting radially outwards. There are three external sectors 36. The external sectors 36 have a peripheral surface in contact with the bore of the outer casing 27. The external sectors 36 occupy an angle of approximately 15 to 40°.

[0048] The support ring 35 comprises internal sectors 37 projecting radially inwards. There are three internal sectors 37. The internal sectors 37 have a convex surface in contact with the periphery of the inner container 26. The internal sectors 37 occupy an angle of approximately 15 to 40°. The external sectors 36 and the internal sectors 37 alternate. The external sectors 36 and the internal sectors 37 are angularly separated from each other. Preferably, three internal sectors 37 and three external sectors 36, each with an angle of approximately 20 to 30°, are alternately distributed and separated by areas without projections, occupying an angle of approximately 40 to 30°, respectively. The support ring 35 is held in place by sufficient friction against the inner container 26 or by permanent attachment.

[0049] The support ring 35 is made of composite material with low thermal conductivity and high mechanical strength.

[0050] The cryogenic tank 2 includes a removable collector 38 passing through the outer casing 27 and the inner container 26 in a sealed manner. The collector 38 includes a straight pipe 39 for drawing liquefied gas from the inner container 26. The pipe 39 is made of insulating material. The collector 38 includes a first end open inside the inner container 26. The collector 38 includes a second end open outside the outer casing 27. The second end is intended to be connected to a line, for example, an outlet line 4, see [reference]. figure 6 The first and second ends are connected by a port. The first end, when assembled, is located near the bottom of the inner container 26. This end is free. Thus, the manifold 38 draws liquefied gas. The withdrawal stops when the liquid level is low. In other words, the inner container 26, when in operation, contains a gaseous phase and a liquid phase. At the end of the filling process, the liquid phase is at its maximum and the gaseous phase is at its minimum. At the end of the withdrawal process, the liquid phase is at its minimum, or even absent, and the gaseous phase is at its maximum. The liquid phase is then withdrawn. Withdrawing the liquid phase relative to the gaseous phase allows for significantly smaller diameter pipes. The compactness of the components downstream of the cryogenic tank 2 is improved. The nozzle 39 is also used for filling with liquefied gas.

[0051] The manifold 38 includes, at its second end, a pad 41 surrounding the rod 39. The pad 41 is made of insulating material. The pad 41 projects beyond the outer casing 27. The pad 41 may have a gripping area for disassembly, for example, during maintenance. The pad 41 has an outer diameter greater than the diameter of the rod 39. The pad 41 forms a removable, sealed head for the cryogenic tank 2.

[0052] A cap assembly comprises the cap pad 41 and a cap cover 45. In the case of an aircraft or drone, the cryogenic tank 2 can be mounted with the cap assembly facing the front of the aircraft and the free end of the nozzle 39 facing the rear of the aircraft to take advantage of the aircraft's general inclination of a few degrees, allowing for more complete filling with liquefied gas and more complete withdrawal of the liquefied gas. The cryogenic tank 2 can also be mounted at an angle, notably by means of a support member of unequal height between the front and rear of the cryogenic tank 2.

[0053] Furthermore, the manifold 38 includes a liquid level gauge 40. The gauge 40 extends along the stem 39. The gauge 40 is connected to the outside of the tank by a wired connection through the buffer 41. The gauge 40 provides an output signal representing the liquid level. The gauge may be capacitive. The accuracy of the gauge is higher when the manifold 38 has a small angle relative to the horizontal. Indeed, for a given gauge resolution and a given height of the inner container 26, an increased length of the inner container 26 allows for a longer gauge and therefore increased accuracy. For example, a gauge at 30° to the horizontal has twice the accuracy of a vertical gauge.

[0054] The manifold 38 includes a gas vent 53 for rapid release in case of overpressure. Vent 53 also serves to vent gases during filling to prevent overpressure. During withdrawal, vent 53 is used to repressurize the system by introducing gas if necessary. Vent 53 is located in the buffer 41 and opens into the inner container 26 near the buffer 41. Vent 53 is equipped with a liquid check valve.

[0055] Vent 53 is located in buffer 41 and opens into inner container 26 near buffer 41. Thus, vent 53 is connected to the gaseous space in inner container 26. Vent 53 is connected to a conduit passing through buffer 41. A valve with an opening pressure lower than the permissible pressure of cryogenic tank 2 can be connected to the conduit. A rupture disc with a rupture pressure lower than the permissible pressure of cryogenic tank 2 can also be connected to the conduit. The valve and rupture disc are mounted in parallel.

[0056] The collector 38 includes a temperature sensor located in the bottom of the buffer 41 on the inner side. The temperature sensor provides temperature information measured in the inner container 26.

[0057] The cryogenic tank 2 includes a thermally insulating neck 42. The neck 42 has a bore. The neck 42 may be made of metal. The metal is chosen for its low thermal conductivity, mechanical strength, flexibility, and hydrogen impermeability. The neck 42 is welded or screwed with a gasket to the inner container 26. The neck 42 is welded or screwed with a gasket to the outer casing 27. The neck 42 is sufficiently flexible to accommodate differences in expansion between the inner container 26 and the outer casing 27. The neck 42 includes an outer wall attached to the inner container 26 and the outer casing 27. The neck 42 includes an inner wall located away from the inner container 26 and the outer casing 27. The inner wall may be attached to the outer wall at the ends of the neck 42.

[0058] The outer wall is tubular. The inner wall is tubular with a bellows-like shape. The inner wall can be made of sheet metal thinner than the sheet metal of the outer wall to increase elastic deformability. The inner wall can have a bellows shape, which increases its capacity for elastic deformation. A bellows shape, for example corrugated, reduces the contact area between the inner wall and the pad 41, resulting in low thermal conductivity.

[0059] Advantageously, the bellows-type inner wall comprises two concentric plates. These plates are nested one inside the other and connected at their ends. This forms a double wall, reducing the risk of leakage. If one of the two plates is punctured, detection can be performed by applying a gas pressure between the two plates that is higher than the pressure in the insulation chamber but lower than atmospheric pressure, and monitoring the change in the applied pressure. If the applied pressure decreases, the larger-diameter plate is leaking to the insulation chamber. If the applied pressure increases, the smaller-diameter plate is leaking to the bore of the neck 42. The neck can then be replaced.Furthermore, if only one of the plates leaks, the insulation chamber maintains its low pressure, ensuring low thermal conductivity, and cryogenic tank 2 remains operational until the next maintenance operation. If a single plate loses its seal, the insulation chamber loses its low thermal conductivity, and cryogenic tank 2 is emptied urgently, resulting in the loss of its contents.

[0060] The neck 42 forms a sealed interface between the manifold 38 on one side and the outer casing 27 and the inner container 26 on the other. The neck 42 maintains a gas-tight seal between the outer casing 27 and the inner container 26, regardless of the position of the manifold 38, or even its absence. The neck 42 is hermetically sealed in a hole provided in the outer casing 27. The neck 42 is hermetically sealed in a hole provided in the inner container 26. The hole in the outer casing 27 and the hole in the inner container 26 are located at one of the rounded ends of the cryogenic tank 2, near the outer diameter of the cryogenic tank 2 at its upper end. The manifold 38 extends beyond the neck 42 outwards at one of its external ends. The collector 38 extends beyond the neck 42 into the interior of the cryogenic tank 2 downwards and towards the other of the rounded ends of the cryogenic tank 2.

[0061] The neck 42 is formed around a portion of the manifold 38. The neck 42 passes through the isolation chamber 29 to allow for pressure-independent removal of the manifold 38 within the isolation chamber 29. The neck 42 has a through hole 43 through which the manifold 38's plug 41 is installed in a removable manner. The contact surface between the neck 42 and the plug 41 can be provided with female annular teeth 44 to increase the leakage path length and improve the mechanical retention of the manifold 38 within the neck. Here, the teeth 44 have chevrons. The plug 41 has a smooth outer surface of revolution when free. The plug 41 is adapted to the neck 42. A slight clearance between the bellows and the plug 41 can be provided. A liquid deflector is provided inside the neck near the storage chamber 28. The plug 41 is made of thermally insulating material.The 41 pad may include a resistant shell and insulating synthetic foam within the shell.

[0062] In the implementation of figures 6 et 7 The neck 42 is welded to the inner container 26 around its outer wall. The neck 42 has a flange superimposed on a flange of the inner container 26. The weld can be performed by electron beam directed at the flanges. The neck 42 is welded to the outer casing 27 around its outer wall at a distance from the weld to the inner container 26. The outer wall of the neck 42 comprises two distinct and separate parts, one connected to the inner container 26, and the other connected to the outer casing 27.

[0063] The inner wall connects the two parts of the outer wall. The inner wall comprises two concentric sheets of metal with a thickness between 0.1 and 0.2 mm. On the outside, the neck 42 includes a flange 54 directed towards the inner wall. The flange 54 provides a watertight seal between the inner and outer walls. A sealing gasket 55 is attached to the flange 54, typically by screwing. The sealing gasket 55 contacts the plug 41 of the manifold 38. The level gauge is not present here.

[0064] The cryogenic tank 2 includes a cover 45 permanently mounted to the manifold 38 and accessible from the outside. The cover 45 is attached to the stem 39 by screws or bolts. The cover 45 is located outside the outer casing 27. The cover 45 is located at the external end of the manifold 38. The cover 45 is leak-proof.

[0065] Cryogenic tank 2 is designed for a working pressure of less than 8 bar, specifically 6 bar.

[0066] Advantageously, the cryogenic tank 2 includes an anti-sway device installed inside the inner container 26. The anti-sway device comprises one or more perforated panels dividing the internal volume of the inner container 26 into several zones. The openings in the perforated panels may have a surface area of ​​approximately 1 to 5% of the total surface area of ​​the perforated panels. The perforated panels may be longitudinal or transverse. The perforated panels reduce the velocity of the liquefied gas within the inner container 26 during accelerations, for example, during takeoff, landing, or atmospheric turbulence.

[0067] Advantageously, the cryogenic tank 2 includes a stiffener inside the inner container 26. The stiffener includes at least one strut or tie connecting opposing regions of the inner container 26. The stiffener allows the rest of the structure of the inner container 26 to be lightened.

[0068] In the isolation chamber 29, a hydrogen-adsorbing material 46, for example a nanoporous material, is installed. In the event of a slight leak, the insulation loss due to the pressure increase in the isolation chamber 29 is reduced. After such a leak, the outer casing 27 is removed to open the isolation chamber 29, and the hydrogen-adsorbing material 46 is removed to desorb the hydrogen, for example by heating.

[0069] A hydrogen presence detector 47 is installed in the isolation chamber 29. The presence of hydrogen is monitored. In the event of a major leak, emergency emptying of the inner container 26 can be initiated. In the event of a minor leak, maintenance can be anticipated. The maintenance operation may include repairing the inner container 26 to remedy the leak, replacing or desorbing the hydrogen adsorbing material, if necessary, and re-evacuating the isolation chamber 29.

[0070] In the embodiment illustrated on the figures 1 à 3 The outer casing 27 comprises two separable parts 48 and 49. The first part 48 comprises an end and a body. The second part 49 comprises an opposite end. The first and second parts are connected in a leak-proof and separable manner by two sealing rings 50 and 51 providing metal-to-metal sealing surfaces by interference. The interference can be cone-on-cone, torus-on-cone, or plane-on-plane, optionally with a hot-applied metal O-ring—in particular, made of a copper alloy—or an elastomer. The interference is achieved by axial tightening, in particular by bolts. The sealing rings 50 and 51 are annular.

[0071] In the embodiment illustrated on the figure 4 The outer casing 27 is made of several sections. Two sections are sealed together by sealing rings 50 and 51 as described above. Sections can be standardized for different inner container capacities 26 with an end section, one or more central sections, and an end section with a hole for the neck. Several support rings 35 can be provided.

[0072] In the embodiment illustrated on the figure 5 The frame 30 of the outer shell 27 comprises annular members 32, longitudinal members 33 parallel to the longitudinal axis, and diagonal braces. The outer shell 27 includes panels 31 of generally triangular shape, each mounted between a member, a longitudinal member, and a brace, and curved panels at the ends. The triangular panels 31 leave the frame 30 exposed. The curved panels cover the frame 30 beyond the members 32.

[0073] In the embodiment illustrated on the figure 6 The distribution circuit 1 includes a first valve 11 for each cryogenic tank 2. The first valve 11 is mounted on the outlet line 4. The first valves 11 are actuated with an open position and a closed position. The intermediate positions of the first valves 11 are dynamic in that the first valves 11 move through these intermediate positions. In other words, the first valves 11 are either fully open or fully closed. The first valves 11 can be located immediately downstream of the flow meters 22.

[0074] The first valves 11 open into a cryogenic distributor 5. The cryogenic distributor 5 may include a common conduit 6 connecting the outlets of the first valves 11. The distributor is cryogenic in that it sees liquid fuel / oxidizer pass through it.

[0075] The cryogenic distributor 5 comprises a plurality of outlets, here three. Each of these outlets is fitted with a secondary valve 12. The secondary valves 12 are actuated with an open position and a closed position. The intermediate positions of the secondary valves 12 are dynamic, meaning that the valves 12 move through these intermediate positions. In other words, the secondary valves 12 are either fully open or fully closed. There are three secondary valves 12 in this configuration.

[0076] Downstream of each second valve 12 is mounted a central tank 7. Three central tanks 7 are provided in this embodiment. Each central tank 7 also serves as a gasifier. Insulation can be omitted. Each central tank 7 receives liquid and supplies gas downstream. A pressure rise or gasification stage occurs in each central tank 7 between filling and emptying. Each central tank 7 is capable of withstanding a maximum operating pressure of approximately 300 to 1000 bar. Each central tank 7 is designed to operate within a temperature range of -253°C to +60°C. The central tanks 7 are two-phase during some of their operating stages and single-phase gaseous during the remaining operating stages. Each central tank 7 can be equipped with a heating element 8.

[0077] Downstream of each central tank 7, a third valve 13 is installed to supply gas, and a pressure regulator 9 is installed downstream of the third valve 13. The pressure regulator 9 reduces the pressure to supply gas at a consumption pressure set by the manufacturer of the consuming component 3. The pressure regulator 9 is active when the pressure in the central tank 7 is higher than the consumption pressure and inactive otherwise. The consumption pressure is lower than the maximum pressure of the central tank 7. The consumption pressure is independent of the maximum pressure of the cryogenic tanks. The third valves 13 are on / off.

[0078] Downstream of each regulator 9, a fourth controlled valve 14 may be provided. The fourth valves 14 are on / off.

[0079] The fourth valves 14 or the pressure regulators 9, depending on the option chosen, open into a manifold 10. The manifold 10 may include a pipe connecting the outlets of the fourth valves 14 or the pressure regulators 9. Gas flows through the manifold 10. The manifold 10 is connected downstream to supply lines 23 leading to the consuming devices 3. Generally, a supply line 23 is provided for each consuming device 3. Each supply line 23 may be equipped with a pilot-operated supply valve 24. The supply valve 24 is variable flow.

[0080] The distribution circuit 1 includes at least one compressor 20 connected to the manifold 10. Generally, two compressors 20 are provided in parallel for redundancy. The compressor 20 is electric. The compressor 20 may be equipped with a pilot-operated upstream valve. The compressor 20 delivers gas into the manifold 10. In particular, the manifold 10 consists of a single pipe in the case of a single consuming device 3.

[0081] Downstream of each central tank 7, a fifth valve 15 is installed to supply gas, and a second manifold 38 is located downstream of the fifth valves 15. The second manifold 38 is connected to the compressor 20. The fifth valves 15 allow the central tanks 7 and the compressor 20 to be isolated. The fifth valves 15 are controlled. The fifth valves 15 are on / off.

[0082] The compressor 20 increases the pressure to supply gas at a pressure equal to the consumption pressure set by the manufacturer of the consuming component 3. The consumption pressure is lower than the maximum pressure in the central tank 7. The compressor 20 allows gas to be drawn from a central tank 7 whose pressure is lower than the consumption pressure to supply the manifold 10 and the consuming components 3. A more complete draining of the central tank 7 increases the operating time supplied by the gas contained in the central tank 7 or reduces the volume of the central tank 7.

[0083] Sufficiently draining the central reservoir 7 to reduce its internal pressure below the pressure in one of the cryogenic reservoirs allows the liquid from the cryogenic reservoir to be transferred to the central reservoir 7 by pressure difference during the subsequent refilling process. Thus, the liquid from the cryogenic reservoir is drawn into the central reservoir 7 until pressure equilibrium is reached. A cryogenic pump is therefore unnecessary, resulting in savings in mass and energy consumption.

[0084] The distribution circuit 1 offers a combination of individual states for each cryogenic tank, each central tank 7, and each consuming unit 3. Several consuming units 3 can be active simultaneously. In normal mode, one cryogenic tank is being emptied while the others are inactive and therefore closed. However, in certain situations, for example, to reduce the pressure in several cryogenic tanks, a special mode can be provided in which several cryogenic tanks are being emptied. The central tanks 7 have a filling mode, a gasification mode, a gas storage mode, and an emptying mode.

[0085] When one of the cryogenic tanks is being emptied, the corresponding first valve 11 is opened and the other first valves 11 are closed. When one of the consuming devices 3 is being supplied, the corresponding supply valve 24 is opened.

[0086] When one of the central reservoirs 7 is in filling mode, the second valve 12 connected to said central reservoir 7 is open, and at least one of the first valves 11 is open. The other second valves 12 are closed, except in the case of simultaneous filling of two central reservoirs 7. The third valve 13 connected to said central reservoir 7 is closed. The fifth valve connected to said central reservoir 7 is closed.

[0087] When one of the central tanks 7 is in gasification mode, the second valve 12 connected to said central tank 7, the third valve 13 connected to said central tank 7, and the fifth valve 15 connected to said central tank 7 are closed. The gasification mode is short-lived, particularly in the case of a warm ambient atmosphere and / or when the central tank 7 is being heated.

[0088] When one of the central tanks 7 is in drain mode, the second valve 12 connected to said central tank 7 is closed. During the initial draining phase, the pressure in the central tank 7 is higher than the consumption pressure. The third valve 13 connected to said central tank 7 is opened, the corresponding fourth valve 14 is opened, and the fifth valve connected to said central tank 7 is closed. The gas undergoes a pressure reduction in the pressure regulator 9 and is supplied to the manifold 10 at the consumption pressure. The gas is then consumed by the consuming device(s) 3.

[0089] At any given time, among three central tanks 7, one is in filling mode, another in gasification and then storage mode, and the third in emptying mode. Since the modes have different durations, it is also possible to find two central tanks 7 in filling mode and the third in emptying mode, or vice versa. It is also possible to find two central tanks 7 in storage mode and the third in emptying mode, or vice versa.

[0090] In the embodiment, a flow meter 22 is arranged at the outlet of each liquid fuel / oxidizer source 2. The flow meters 22 make it possible to know with sufficient accuracy the quantity of liquid supplied to such central reservoir 7.

[0091] In this embodiment, the distribution circuit 1 comprises a control unit 25 receiving an external command, for example, from external consumer devices 3 located outside the aircraft storage system or from a central aircraft control unit, and liquid flow data from flow meters 22. The control unit 25 generates and sends commands to the first, second, third, fourth, and fifth controlled valves and to the controlled supply valves 24. The commands can be "open" or "closed." The control unit 25 manages this combination of individual states.

[0092] Alternatively, the first 11 valves can be replaced by at least one multiport valve with several inlets and one outlet. In this case, it is advantageous to provide a multiport valve with mixed positions, including at least one position for simultaneously emptying two or more cryogenic tanks 2 to reduce their pressure while preventing loss to the atmosphere.

[0093] Alternatively, the second valves 12 can be replaced by at least one multi-way valve having one inlet and several outlets, one per central tank 7. Said multi-way valve forms a distributor.

[0094] Alternatively, the regulators 9 are replaced by a single regulator 9, with the third valves 13 opening into this single regulator 9. In this case, the third valves 13 can be replaced by at least one multiport valve having several inlets and one outlet to the regulator. The fourth valves 14 are then replaced by a single fourth valve 14, which may be unpiloted.

[0095] Alternatively, the fifth valves 15 can be replaced by at least one multi-way valve having several inlets, one per central tank 7, and an outlet to the compressor 20 or compressors 20. Said multi-way valve forms a manifold 10.

[0096] Since cryogenic tanks 2 are subject to evaporation from the liquid, a gas collection circuit can be provided in the upper part of the cryogenic tanks 2. The collection circuit can be activated above a threshold pressure by a calibrated pressure valve. The collection circuit includes a compressor to reinject the gas downstream, for example, between the fifth valves 15 and the compressor 20.

[0097] Optionally, additional flow meters are installed at the inlet of each buffer tank. Redundancy of liquid flow measurement is ensured.

[0098] The capacity of the cryogenic tank device is between 10 kg and 10000 kg of gas, preferably between 100 kg and 10000 kg of gas.

[0099] A temporary storage and gasification tank 7 is provided for pressurizing the gas supplied by the device. An upstream valve 12 is provided to be open for liquid flow during the filling phase of the temporary storage tank 7 and closed outside of the filling phase. At least one downstream valve 13, 15 is provided to be open for gas flow during the emptying phase of the temporary storage tank 7 and closed outside of the emptying phase. Both the upstream and downstream valves are closed during the gasification phase. The upstream and downstream valves are on / off controlled. At least one compressor 20 is located downstream of the downstream valve 15. The compressor 20 is active at the end of the emptying phase to reduce the pressure in the temporary storage tank 7 to a value lower than the pressure in the device. A pressure regulator 9 is located downstream of the downstream valve.The pressure regulator 9 is active at the beginning of the emptying phase to bring the outlet gas pressure to a value lower than the pressure in the temporary storage tank 7.

[0100] The railway, road or maritime cryogenic gas storage tank device, of spherical or elongated shape, particularly around a longitudinal axis, comprises an inner container defining a liquefied gas storage chamber 28, an outer casing 27 containing the inner container and made of several removable parts allowing access to the inner container, the outer casing 27 being made of a material resistant to temperatures from less than -60°C to at least +80°C, an isolation chamber 29 defined between the inner container and the outer casing, the reduced pressure isolation chamber 29 having a helium tightness equal to or better than 10⁻⁹ millibar*litre / second defined between the inner container and the outer casing, two connections, at least one of which is a sliding connection, supporting the inner container and carried by the outer casing,a support ring mounted between the inner container and the outer casing at a distance from the connections in the insulation chamber, a removable manifold 38 passing through the outer casing and the inner container in a sealed manner, and a flexible, thermally insulating neck 42 forming a sealed interface between the manifold 38 on one side and the outer casing and the inner container on the other, the neck 42 being formed around a portion of the manifold 38, the neck 42 passing through the insulation chamber to allow dismantling of the manifold 38 independent of the pressure in the insulation chamber.

[0101] The storage and distribution assembly includes a cryogenic hydrogen storage tank device, comprising an inner container defining a liquefied gas storage chamber, an outer shell containing the inner container, a sealed isolation chamber defined between the inner container and the outer shell, a removable liquefied gas collector passing through the outer shell and the inner container in a sealed manner, the collector extending over a diameter or diagonal of the inner container and having a free end near a bottom of the inner container, a liquefied gas line supplied by the collector, a temporary storage tank forming a gasification element for pressurizing the gas supplied by the device, an upstream valve intended to be open for liquid flow during a filling phase of the temporary storage tank and closed outside of the filling phase,a downstream valve designed to be open for gas flow during a draining phase of the temporary storage tank and closed outside of the draining phase, the upstream and downstream valves being closed during a gasification phase, the upstream and downstream valves being controlled on or off, and a pressure regulator located downstream of the downstream valve, said pressure regulator being active at the beginning of the draining phase to reduce the outlet gas pressure to a value lower than the pressure in the temporary storage tank.

Claims

1. Cryogenic tank device for rail, road or sea transport, intended for on-board use, for gas storage, spherical or elongated in shape, comprising an inner container (26) defining a liquefied gas storage chamber (28), an outer shell (27) containing the inner container (26), an insulation chamber (29) defined between the inner container (26) and the outer shell (27), a removable collector (38) passing through the outer shell (27) and the inner container (26) in a sealed manner, characterised in that the outer shell (27) is made up of a plurality of detachable parts allowing access to the inner container (26), the outer shell (27) is made of material resistant to temperatures of less than -60 °C to at least +80°C, the insulation chamber (29) is at reduced pressure exhibiting a helium leak tightness equal to or better than 10-9 millibar*litre / second defined between the inner container (26) and the outer shell (27), the outer shell comprises two connections, at least one of which is a sliding connection, supporting the inner container (26) and carried by the outer shell (27), and in that the device comprises a thermally insulating flexible collar (42) forming a sealed interface between the collector (38) on the one hand and the outer shell (27) and the inner container (26) on the other hand, the collar (42) being arranged around a portion of the collector (38), the collar (42) passing through the insulation chamber (29)to allow for the disassembly of the collector (38) independent of the pressure in the insulation chamber (29).

2. Device according to Claim 1, comprising a thermally insulating plug assembly removably mounted on the collector (38) and accessible from the outside.

3. Device according to one of the preceding claims, wherein one of the connections comprises an axial concavity in the outer shell (27) receiving and supporting an axial projection of the inner container (26) .

4. Device according to any one of the preceding claims, wherein the outer shell (27) comprises a frame (30), sealed panels (31), pressure-resistant seals between the frame (30) and the panels (31) and / or between the panels (31).

5. Device according to the preceding claim, wherein the frame (30) comprises cross members (32) and longitudinal members (33).

6. Device according to Claim 4 or 5, wherein the seals are housed in grooves and, in the free state, protrude from the grooves with a height of less than 10% of a height of said seals.

7. Device according to any one of the preceding claims, comprising an anti-sloshing member inside the inner container (26) and a stiffener inside the inner container (26), preferably a spacer or a tie rod.

8. Device according to any one of the preceding claims, comprising at least one support ring (35) mounted between the inner container (26) and the outer shell (27) away from the connections in the insulation chamber (29).

9. Device according to one of the preceding claims, wherein a hydrogen adsorbing material is disposed in the insulation chamber (29) and a hydrogen presence detector is installed in the insulation chamber (29).

10. Assembly comprising a device according to one of the preceding claims, a temporary storage tank (7) forming a gasification member for increasing the pressure of the gas supplied by the device, an upstream valve (12) provided to be opened for liquid flow during a filling phase of the temporary storage tank (7) and closed outside the filling phase, a downstream valve (13, 15) being provided to be open for the gas flow during a phase of emptying the temporary storage tank (7) and closed outside the emptying phase, the upstream valve and the downstream valve being closed during a gasification phase, the upstream valve and the downstream valve being controlled on or off, and a compressor (20) disposed downstream of the downstream valve (15), said compressor (20) being active at the end of the emptying phase to bring the pressure in the temporary storage tank (7) to a value lower than the value of the pressure in the device, and a pressure reducer (9) disposed downstream of the downstream valve, said pressure reducer (9) being active at the beginning of the emptying phase to bring the pressure of the gas at the outlet to a value lower than the pressure in the temporary storage tank (7).