STORAGE TANK ARRANGEMENT

Abstract

A storage tank arrangement, optionally suitable for a vehicle, includes a storage tank for storage of volatile liquids including a tank inner wall and a tank outer wall separated by an insulating inter-wall region, inner and outer feedthrough arrangements, each configured to form a seal with a respective surface of the storage tank arrangement and to permit passage therethrough, and/or permit connection of, of one or more sensors, and a container external of the storage tank outer wall, configured to inhibit egress of the contents of the storage tank in the event of a failure of at least one of the inner and outer feedthrough arrangements. A vehicle including such a storage tank arrangement is also disclosed.

Claims

1. A storage tank arrangement suitable for storage of liquid gas, comprising: a storage tank suitable for storage of liquid gas comprising a storage tank inner wall and a storage tank outer wall separated by an insulating inter-wall region; inner and outer feedthrough arrangements, each configured to form a seal with a respective surface of the storage tank arrangement and to permit passage therethrough of one or more sensor cords, and/or permit connection of one or more sensors; and the inner and outer feedthrough arrangements defining a feedthrough path therebetween, the feedthrough path being at least partially located in a feedthrough region between the storage tank inner and outer walls, the feedthrough region being isolated from an adjacent inter-wall region between the storage tank inner and outer walls.

2. The storage tank arrangement of claim 1, wherein the feedthrough region is isolated from the adjacent inter-wall region by a fluid-impermeable divider, wherein the fluid-impermeable divider is provided by a spacer arrangement for maintaining the storage tank inner and outer walls in spaced relationship.

3. The storage tank arrangement of claim 2, wherein a portion of the spacer arrangement extends externally of the storage tank outer wall, and a portion of the spacer arrangement is optionally located inwardly of the storage tank inner wall.

4. The storage tank arrangement of claim 2, wherein the spacer arrangement comprises an inner attachment portion for securing the spacer arrangement to the storage tank inner wall, an outer attachment portion for securing the spacer arrangement to the storage tank outer wall and a spacing portion for maintaining the inner and outer attachment portions in spaced relationship.

5. The storage tank arrangement of claim 4, wherein the spacing portion provides the feedthrough region, and/or the spacing portion comprises an elongate hollow portion.

6. The storage tank arrangement of claim 1 comprising one or more cord guides for securing one or more cords.

7. The storage tank arrangement of claim 6, wherein one or more cord guides is or are located between the inner and outer feedthrough arrangements, and/or wherein the or each cord guide comprises a cord guide mount for mounting the cord guide to the storage tank arrangement and a carrier portion that is attachable to the cord guide mount, the carrier portion being attachable to the cord guide mount in a plurality of different orientations, and/or wherein the or each cord guide comprises a clamp for securing one or more cords.

8. The storage tank arrangement of claim 1, wherein one or more of the inner and outer feedthrough arrangements comprises one or more feedthrough elements, each feedthrough element being configured to form a seal with a respective surface of the storage tank arrangement and to permit passage therethrough of one or more sensor cords, and/or permit connection of one or more sensors.

9. The storage tank arrangement of claim 8, wherein a first feedthrough element is configured to form a seal with a first portion of a surface of the storage tank inner wall or the storage tank outer wall, and the second feedthrough element is configured to form a seal with a second portion of the surface of the storage tank inner wall or the storage tank outer wall.

10. The storage tank arrangement of claim 1, wherein the inner feedthrough arrangement is sealed to the storage tank inner wall or is sealed to a third wall, the third wall being internal of the storage tank inner wall.

11. The storage tank arrangement of claim 1, wherein each of the inner feedthrough arrangement and outer feedthrough arrangement is sealed to a respective internal surface of a conduit.

12. The storage tank arrangement of claim 11, wherein the conduit comprises a two-walled conduit, with a first, conduit inner wall spaced from a second, conduit outer wall, the inner feedthrough arrangement being sealed to an internal surface of the first, conduit inner wall and the outer feedthrough arrangement being sealed to an internal surface of the conduit outer wall or wherein the inner and outer feedthrough arrangements are sealed to a same internal surface of the conduit, the inner feedthrough arrangement being sealed to a first portion of the conduit and the outer feedthrough arrangement being sealed to a second portion of the conduit, the second portion of the wall being located outward of the first portion of the conduit.

13. The storage tank arrangement of claim 11, wherein the conduit comprises a detachable conduit portion comprising one or both of the inner and outer feedthrough arrangements.

14. The storage tank arrangement of claim 1, wherein the inner and outer feedthrough arrangements are configured to define a region therebetween for one or more sensor heads.

15. The storage tank arrangement of claim 1, wherein one or both of the inner and outer feedthrough arrangements comprise(s) a plurality of feedthrough ports, each one being for the passage therethrough of one or more sensor cords, or for connection to one or more sensors.

16. The storage tank arrangement of claim 1 comprising one or more further feedthrough arrangement(s) in addition to the inner and outer feedthrough arrangements.

17. A storage tank arrangement suitable for storage of liquid gas, comprising: a storage tank suitable for storage of liquid gas comprising a tank inner wall and a tank outer wall separated by an insulating inter-wall region; inner and outer feedthrough arrangements, each configured to form a seal with a respective surface of the storage tank arrangement and to permit passage therethrough of one or more sensor cords, and/or permit connection of one or more sensors; and a container external of the storage tank outer wall, the container being configured to inhibit egress of the contents of the storage tank in an event of a failure of at least one of the inner and outer feedthrough arrangements.

18. A vehicle comprising the storage tank arrangement of claim 1 and one or more engines configured to receive fuel from the storage tank arrangement.

19. A storage tank arrangement suitable for storage of liquid gas, comprising: a storage tank suitable for storage of liquid gas comprising a storage tank inner wall and a storage tank outer wall separated by an insulating inter-wall region; inner and outer feedthrough arrangements, each configured to form a seal with a respective surface of the storage tank arrangement and to permit passage therethrough of one or more sensor cords, and/or permit connection of one or more sensors; and a conduit which is in gaseous communication with an interior of the storage tank, wherein the conduit comprises: a detachable conduit portion, which is detachable to, and removable from, a further conduit portion, the detachable conduit portion comprising at least one of the inner and outer feedthrough arrangements.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0094] Embodiments of the disclosure herein will now be described by way of example only with reference to the accompanying schematic drawings of which:

[0095] FIG. 1 shows a schematic cross-sectional view of a storage tank arrangement according to a first embodiment of the disclosure herein;

[0096] FIG. 2 shows a schematic cross-sectional view of a storage tank arrangement according to a second embodiment of the disclosure herein;

[0097] FIG. 3 shows a schematic cross-sectional view of a storage tank arrangement according to a third embodiment of the disclosure herein;

[0098] FIG. 4 shows a schematic cross-sectional view of a storage tank arrangement according to a third embodiment of the disclosure herein;

[0099] FIG. 5 shows a perspective view of part of the storage tank arrangement of FIG. 4;

[0100] FIG. 6 shows a schematic view of an aircraft according to an embodiment of the disclosure herein;

[0101] FIG. 7 shows a perspective view of a pair of cord guides shown in FIG. 5;

[0102] FIG. 8 shows a schematic representation of an example of a method according to another embodiment of the disclosure herein; and

[0103] FIG. 9 shows a schematic representation of a further example of a method according to yet another embodiment of the disclosure herein.

DETAILED DESCRIPTION

[0104] An example of an embodiment of a storage tank arrangement in accordance with the first and second aspects of the disclosure herein will now be described with reference to FIG. 1. The storage tank arrangement is denoted generally by reference numeral 1 and comprises a storage tank 2 suitable for the storage of volatile liquids, in this case liquid hydrogen. In this case, the storage tank arrangement is a fuel tank arrangement, storage tank 2 being a fuel tank of an aircraft. The storage tank 2 comprises a tank inner wall 3 and a tank outer wall 4 separated by an insulating inter-wall region 5. The tank inner wall 3 and outer wall 4 are maintained in spaced relationship by one or more spacers (not shown). The insulating inter-wall region 5 is a low-pressure region, the low pressure typically being achieved using a vacuum pump (not shown). The storage tank arrangement 1 comprises inner 6 and outer 7 feedthrough arrangements. Inner feedthrough arrangement 6 comprises feedthrough member 6a, which forms a seal with a respective part 8a of a surface of the storage tank arrangement 1. Feedthrough member 6a also permits passage therethrough of one or more sensors (not shown). Inner feedthrough arrangement 6 also comprises feedthrough member 6b, which forms a seal with a respective part 8b of a surface of the storage tank arrangement 1. Feedthrough member 6b also permits passage therethrough of one or more sensors (not shown). Both feedthrough members 6a, 6b form a seal against an outer surface of the tank inner wall 3. Feedthrough member 6b extends through an aperture (not labelled) in tank inner wall 3. Inner feedthrough arrangement 6 also comprises feedthrough member 6c, which abuts against and forms a seal with feedthrough member 6b. Outer feedthrough arrangement 7 comprises a feedthrough member 7a that forms a seal with a surface 9 of the storage tank arrangement 1, in this case, an outer surface of a container 10. Feedthrough member 7a permits passage therethrough of one or more sensors (not shown). Feedthrough members 7a, 6a, 6b comprise one or more channels (not labelled) in which sensor wires may be located. The material forming the channels is typically a resiliently-deformable material that forms a sealing engagement with a sensor wire present in the channel. The inner 6 and outer 7 feedthrough arrangements are aligned to permit electrical wires and/or optical fibers to be pass from the exterior to the interior 20 of the storage tank 2, while minimizing the risk of leaks from the interior 20 of the storage tank 2. This is achieved by providing suitable seals between (i) the respective feedthrough arrangement and a surface of the storage tank arrangement 1, and (ii) the respective feedthrough arrangement and any electrical wires and/or optical fibers that pass through the respective feedthrough arrangement.

[0105] As mentioned above, the storage tank arrangement 1 comprises a container 10. The container 10 is external of the storage tank outer wall 4, and it is configured to inhibit egress of the contents of the storage tank 2 from the storage tank 2 in the event of a failure of at least one of the inner 6 and outer 7 feedthrough arrangements. Container 10 is attached to storage tank outer wall 4, and forms a volume 18 between the container 10 and storage tank outer wall 4.

[0106] The storage tank arrangement 1 is also configured so that, in the event that the inner feedthrough arrangement 6 fails, the contents of the storage tank 2 are not permitted to enter the vast majority of the inter-wall region 5, the escaped contents being contained in a very small portion of the inter-wall region that is isolated from the vast majority of the inter-wall region. Entry of hydrogen gas into the inter-wall region 5 would lead to an increase in pressure in the inter-wall region 5, which would lead to a reduction in the thermal insulation properties of the inter-wall region, leading to unwanted heating of the contents of the storage tank 2. In this connection, the inner 6 and outer 7 feedthrough arrangements define a feedthrough path 45 therebetween, the feedthrough path 45 being at least partially located in a feedthrough region 12 between the storage tank inner 3 and outer 4 walls, the feedthrough region 12 being isolated from an adjacent 5a inter-wall region between the storage tank inner 3 and outer 4 walls. Feedthrough region 12 is isolated from the rest of the inter-wall region 5 by a fluid-impermeable divider 13 so that there is no fluid communication between feedthrough region 12 and the rest of the inter-wall region 5. During use, volume 18 and feedthrough region 12 are evacuated and are therefore at low pressure, with an aperture 16 in the storage tank outer wall 4 providing fluid communication between volume 18 and feedthrough region 12. Aperture 16 also permits electrical wires and/or optical fibers to pass therethrough. In the event of failure of inner feedthrough arrangement 6, hydrogen gas passes from the relatively-high pressure interior 20 of the storage tank 2 into the feedthrough region 12 and volume 18. Divider 13 prevents the hydrogen gas from entering the remainder of the inter-wall region 5. Container 10 inhibits escape of hydrogen gas into the ambient atmosphere.

[0107] Container 10 is provided with an aperture 14 that provides access to the interior of container 10 and, via aperture 16, to feedthrough region 12. A cover 15 is provided for aperture 14. The provision of the access aperture 14 means that a cable or cord overlength is not required during cord installation.

[0108] A sensor cord passing through the outer and inner feedthroughs is shown by reference numeral 17.

[0109] The terms inner and outer in relation to inner feedthrough arrangement and outer feedthrough arrangement refer to the relative positions of the inner feedthrough arrangement and outer feedthrough arrangement. The inner feedthrough arrangement need not be the innermost feedthrough arrangement and the outer feedthrough arrangement need not be the outermost feedthrough arrangement, as will be discussed below in relation to the storage tank arrangement of FIGS. 4 and 5.

[0110] An example of a further embodiment of a storage tank arrangement in accordance with the first and third aspects of the disclosure herein will now be described with reference to FIG. 2. The storage tank arrangement is denoted generally by reference numeral 101 and comprises a storage tank 102 suitable for the storage of volatile liquids, in this case liquid hydrogen. Once again, storage tank 102 is an aircraft fuel tank. The storage tank 102 comprises a tank inner wall 103 and a tank outer wall 104 separated by an insulating inter-wall region 105. The tank inner wall 103 and outer wall 104 are maintained in spaced relationship by one or more spacers (not shown). The insulating inter-wall region 105 is a low-pressure region, the low pressure typically being achieved using a vacuum pump (not shown). The storage tank arrangement 101 comprises inner 106 and outer 107 feedthrough arrangements. Inner feedthrough arrangement 106 comprises feedthrough member 106a, which forms a seal with a respective surface 108 of the storage tank arrangement 101. Feedthrough member 106a also permits passage therethrough of one or more sensors (not shown). Feedthrough member 106a forms a seal against an inner surface of the conduit inner wall 122 of a two-walled conduit 121. Conduit 121 has a conduit inner wall 122 and a conduit outer wall 123 separated by a conduit inter-wall region 130. Outer feedthrough arrangement 107 comprises a feedthrough member 107a that forms a seal with a surface 109 of the storage tank arrangement 101, in this case, an inner surface of the conduit outer wall 123.

[0111] Conduit outer wall 123, feedthrough member 106a and feedthrough member 107a define a region 125 that may be used to detect for leaks. In this connection, a pressure sensor 127 extends into leak detection region 125. In the event of a failure of inner feedthrough arrangement 106, hydrogen gas will enter leak detection region 125, changing the pressure in leak detection region 125 sufficiently so that the change in pressure will be detected by pressure sensor 127. Alternatively, a hydrogen sensor may be used instead of a pressure sensor. Further sensors 128 extend through both the outer 107 and inner 106 feedthrough arrangements into the interior 120 of storage tank 102. Those sensors may be of any suitable type, such as temperature sensors, pressure sensors, sensors for the detection and/or measurement of liquid hydrogen, sensors for the detection and/or measurement of gaseous hydrogen.

[0112] Feedthrough members 106a, 107a may have one or more of the features described above in relation to the storage tank arrangement 1 described above in relation to FIG. 1.

[0113] Storage tank arrangement 101 comprises a container 110. The container 110 is external of the storage tank outer wall 104, and it is configured to inhibit egress of the contents of the storage tank 102 from the storage tank 102 in the event of a failure of at least one of the inner 106 and outer 107 feedthrough arrangements. Container 110 is attached to storage tank outer wall 104 and forms a volume 118 between the container 110 and storage tank outer wall 104.

[0114] Conduit 121 extends into the interior 120 of storage tank 102, and also extends into volume 118 defined by container 110 and storage tank outer wall 104. A removable conduit portion 131 is removably attached to conduit further portion 140 by a suitable connector 126, which permits removal and reattachment of removable conduit portion 131. Conduit further portion 140 is attached to storage tank 102. Removable conduit portion 131 comprises both the inner 106 and outer 107 feedthrough arrangements, and leak detection region 125. The removability of removable conduit portion 131 facilitates easier replacement and/or servicing of the inner 106 and outer 107 feedthrough arrangements.

[0115] Storage tank arrangement 101 is provided with a bellows 129 which permits relative movement of the storage tank inner 103 and outer 104 walls, for example, movement that may occur due to shrinkage and/or expansion of the respective walls, dependent on the temperature to which those walls are subjected.

[0116] A further example of a further embodiment of a storage tank arrangement in accordance with the first and third aspects of the disclosure herein will now be described with reference to FIG. 3. The storage tank arrangement is denoted generally by reference numeral 201 and comprises a storage tank 202 suitable for the storage of volatile liquids, in this case liquid hydrogen. The storage tank 202 is an aircraft fuel tank. The storage tank 202 comprises a tank inner wall 203 and a tank outer wall 204 separated by an insulating inter-wall region 205. The tank inner wall 203 and outer wall 204 are maintained in spaced relationship by one or more spacers (not shown). The insulating inter-wall region 205 is a low-pressure region, the low pressure typically being achieved using a vacuum pump (not shown). The storage tank arrangement 201 comprises inner 206 and outer 207 feedthrough arrangements. Inner feedthrough arrangement 206 comprises feedthrough member 206a, which forms a seal with a respective surface 208 of the storage tank arrangement 201. Feedthrough member 206a also permits passage therethrough of one or more sensors (not shown). Feedthrough member 206a forms a seal against an inner surface of the conduit inner wall 222 of a two-walled conduit 221. Conduit 221 has a conduit inner wall 222 and a conduit outer wall 223 separated by a conduit inter-wall region 230. Outer feedthrough arrangement 207 comprises a feedthrough member 207a that forms a seal with a surface 209 of the storage tank arrangement 201, in this case, an inner surface of the conduit inner wall 222.

[0117] Conduit inner wall 222, feedthrough member 206a and feedthrough member 207a define a region 225 that may be used to detect for leaks. It is worth noting that region 225 in the storage tank arrangement 201 of FIG. 3 is far smaller than region 125 described above in relation to storage tank arrangement 101 of FIG. 2. A pressure sensor 227 extends into leak detection region 225, which is sufficiently large to accommodate pressure sensor 227, but no larger. In the event of a failure of inner feedthrough arrangement 206, hydrogen gas will enter leak detection region 225, changing the pressure in leak detection region 225. Alternatively, a hydrogen sensor may be used instead of a pressure sensor. Further sensors 228 extend through both the outer 207 and inner 206 feedthrough arrangements into the interior 220 of storage tank 202. Those sensors may be of any suitable type, such as temperature sensors, pressure sensors, sensors for the detection and/or measurement of liquid hydrogen, sensors for the detection and/or measurement of gaseous hydrogen.

[0118] Feedthrough members 206a, 207a may have one or more of the features described above in relation to the storage tank arrangement 1 described above in relation to FIG. 1.

[0119] Storage tank arrangement 201 comprises a container 210. The container 210 is external of the storage tank outer wall 204, and it is configured to inhibit egress of the contents of the storage tank 202 from the storage tank 202 in the event of a failure of at least one of the inner 206 and outer 207 feedthrough arrangements. Container 210 is attached to storage tank outer wall 204 and forms a volume 218 between the container 210 and storage tank outer wall 204.

[0120] In contrast to the storage tank arrangement of FIG. 2, conduit 221 does not extend into the interior 220 of storage tank 202. Conduit 221 extends outwardly from storage tank inner 203 and outer 204 walls. Conduit inner wall 222 is attached to storage tank inner wall 203 and conduit outer wall 223 is attached to storage tank outer wall 204 such that inter-wall region 205 is in fluid communication with conduit inter-wall region 230. Conduit 221 extends into volume 218 define by container 210 and storage tank outer wall 204. A conduit inner portion 240 is attached to storage tank 102. Conduit outer portion 231 is removably attached to conduit inner portion 240 by a suitable connector 226, which permits removal and reattachment of conduit outer portion 231. Conduit outer portion 231 comprises both the inner 206 and outer 207 feedthrough arrangements, and leak detection region 225. The removability of conduit outer portion 231 facilitates easier replacement and/or servicing of the inner 206 and outer 207 feedthrough arrangements.

[0121] Storage tank arrangement 201 is provided with a bellows 229 which permits relative movement of the storage tank inner 203 and outer 2104 walls, for example, movement that may occur due to shrinkage and/or expansion of the respective walls, dependent on the temperature to which those walls are subjected.

[0122] Yet another example of a further embodiment of a storage tank arrangement in accordance with the second aspect of the disclosure herein will now be described with reference to FIGS. 4, 5 and 7. The storage tank arrangement is denoted generally by reference numeral 301 and comprises a storage tank 302 suitable for the storage of volatile liquids, in this case liquid hydrogen. The storage tank 302 is an aircraft fuel tank. The storage tank 302 comprises a tank inner wall 303 and a tank outer wall 304 separated by an insulating inter-wall region 305. The tank inner wall 303 and outer wall 304 are maintained in spaced relationship by a spacer arrangement shown in FIG. 5 and denoted generally by reference numeral 3000. The spacer arrangement 3000 comprises an inner attachment portion 3003 in the form of a flange that is attached to the storage tank inner wall 303. The spacer arrangement 3000 comprises an outer attachment portion 3004 in the form of a flange that is attached to the storage tank outer wall 304. The spacer arrangement 3000 also comprises a spacing portion 341 in the form of a cylindrical portion which acts as a spacer for the inner 3003 and outer 3004 attachment portions, and therefore acts as a spacer for the storage tank inner 303 and outer 304 walls. The spacer arrangement 3000 is sometimes known to those skilled in the art as a polar mount. The insulating inter-wall region 305 is a low-pressure region, the low pressure typically being achieved using a vacuum pump (not shown). The storage tank arrangement 301 comprises inner 306 and outer 307 feedthrough arrangements. Inner feedthrough arrangement 306 comprises four feedthrough members 351, 352, 353, 354 in a plate 3006 mounted in wall 340. Wall 340 is typically provided as part of the spacer arrangement 3000. Wall 340 and inner attachment portion 3003 define a space 3005 that is provided with insulation (not shown). Each feedthrough member 351, 352, 353, 354 forms a seal against plate 3006. Each feedthrough member 351, 352, 353, 354 provides a port for the connection of an electrical wire and/or optical fiber. Outer feedthrough arrangement 307 comprises four feedthrough members 361, 362, 363, 364 mounted in a wall (not labelled) of cylinder 341. Each feedthrough member 361, 362, 363, 364 forms a seal against the wall of cylinder 341. Each feedthrough member 361, 362, 363, 364 provides a port for the connection of an electrical wire and/or optical fiber. An electrical cable (shown collectively as 370) extends between each respective pair (351, 361), (352, 362), (353, 363) and (354, 364) of feedthrough members. This facilitates simple connection of sensors.

[0123] Storage tank arrangement 301 is configured so that, in the event that the inner feedthrough arrangement 306 fails, the contents of the storage tank 302 are not permitted to enter the vast majority of the inter-wall region 305. Inner 306 and outer 307 feedthrough arrangements define a feedthrough path 345 therebetween, the feedthrough path 345 being at least partially located in a feedthrough region 312 between the storage tank inner 303 and outer 304 walls, the feedthrough region 312 being isolated from the remainder of inter-wall region 305 between the storage tank inner 303 and outer 304 walls. Feedthrough region 312 is isolated from the remainder of the inter-wall region 305 by a wall of the cylinder 341 which wall acts as a fluid-impermeable divider 313 so that there is no fluid communication between feedthrough region 312 and the remainder of inter-wall region 305. During use, the interior of cylinder 341 is at ambient pressure. In the event of failure of inner feedthrough arrangement 306, hydrogen gas passes from the relatively-high pressure interior 320 of the storage tank 302 into the interior of the cylinder 341. Divider 313 prevents the hydrogen gas from entering the inter-wall region 305.

[0124] Cylinder 341 comprises an aperture 314 through which the interior of the cylinder 341 can be accessed. Endplate 315 acts as a removable cover that facilitates access to aperture 314. Furthermore, outer feedthrough arrangement 307 is located in a removable access plate 310, which access plate 310 covers an access aperture (not shown).

[0125] Vacuum port 371 is provided to facilitate evacuation (and repressurization) of the feedthrough region 312. Evacuation of the feedthrough region 312 also evacuates the space 3005 between wall 340 and inner attachment portion 3003. This reduces the conduction of heat into the interior 320 of the storage tank.

[0126] Two cable guides 381, 382 are provided inside cylinder 341, as best shown in FIG. 7. Each cable guides 381, 382 comprises a mount 385, 386 having a circular perimeter which is attached to the interior surface of the cylinder 341 wall. Each cable guide 381, 382 comprises a carrier portion 387, 388, which is generally circular in shape and which is attached to the outer surface of each mount 385, 386. Each carrier portion 387, 388 is provided with a plurality of curved slots, two of which are labelled 389, 390. Those slots receive a fixing member (not shown). The carrier portion 387, 388 may be rotated relative to the mount 385, 386 by an amount dictated by the length of the slots. This allows the orientation of the cable guide to be adjusted, but does not allow over-rotation of the cable guide which may cause cables or cords to cross. Each carrier portion 387, 388 comprises a comprises a clamp member 383, 384 for securing cables. Each cable guide 381, 382 is provided with a sensor mount 391, 392 in which sensors 393, 394 are mounted. Sensor 393 is a pressure sensor and sensor 394 is a hydrogen sensor.

[0127] The present feedthrough arrangement 301 makes use of an existing part of a storage tank (the polar mount or cylinder 341), therefore no extra or new structures are needed that potentially introduce new leakage paths into the storage tank.

[0128] An example of an embodiment of a vehicle, in this case an aircraft, in accordance with the fourth aspect of the disclosure herein will now be described with reference to FIG. 6. The aircraft is denoted generally by reference numeral 400 and is a narrow bodied, single aisle aircraft. The aircraft 400 comprises two engines 403, 404, each mounted on a respective wing 401, 402. Each engine 403, 404 is configured to receive liquid hydrogen fuel from a respective storage tank arrangement 1L, 1R, located in a respective wing 401, 402.

[0129] An example of an embodiment of a method of sensing a parameter in a storage tank suitable for the storage of liquid gas will now be described with reference to FIG. 8. The method is denoted generally by reference numeral 800 and comprises transmitting 801 signals via a sensor cord located in a feedthrough path 45, 345 to a sensor head, the feedthrough path 345 being at least partially located in a feedthrough region 12, 312 between the storage tank inner 3, 303 and outer 4, 304 walls, the feedthrough region being isolated from an adjacent inter-wall region 5, 305 between a storage tank inner 3, 303 and a storage tank outer wall 4, 304. The method 800 also comprises receiving 802 signals via the sensor cord from the sensor head.

[0130] An example of an embodiment of a method of sensing a parameter in a storage tank suitable for the storage of liquid gas will now be described with reference to FIG. 9. The method is denoted generally by reference numeral 900. The method 900 comprises transmitting 901 signals to a sensor head via a sensor cord located in a container 10, 110, 210 external of the storage tank outer wall 4, 104, 204. The method also comprises receiving 902 signals from the sensor head via the sensor cord located in the container 10, 110, 210.

[0131] While the present invention has been described and illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the disclosure herein lends itself to many different variations not specifically illustrated herein. By way of example only, certain possible variations will now be described.

[0132] The examples above describe storage tank arrangements that comprise a container for inhibiting egress of the contents of the storage tank in the event of failure of one or more feedthrough arrangements. Those skilled in the art will realize that such containers are not needed for the storage tank arrangements of the second aspect of the disclosure herein.

[0133] The examples above describe storage tank arrangements for the storage of liquid hydrogen. Those skilled in the art will realize that the disclosure herein may be used in relation to storage tank arrangements for the storage of other volatile liquids, such as liquid petroleum gas, liquid nitrogen or liquid oxygen.

[0134] The examples above describe storage tank arrangements used as aircraft fuel tanks. Those skilled in the art will realize that the storage tank arrangements of the disclosure herein may be used in other vehicles, such as land-based vehicles, such as road and/or rail-based vehicles, and in water-based vehicles, such as boats and ships.

[0135] The examples above describe storage tank arrangements used as aircraft fuel tanks. Those skilled in the art will realize that although the storage tank arrangements of the disclosure herein are of particular relevance to vehicles, the storage tank arrangements of the disclosure herein may be used other than in or with a vehicle.

[0136] Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the disclosure herein, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the disclosure herein that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, while of possible benefit in some embodiments of the disclosure herein, may not be desirable, and may therefore be absent, in other embodiments.

[0137] While at least one example embodiment of the 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 example embodiment(s). In addition, in this disclosure, the terms comprise or comprising do not exclude other elements or steps, the terms a, an 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.