airship

Abstract

To disclose an airship suitable as transportation means of hydrogen.SOLUTION: An airship includes: a main air sac filled with floating gas; and at least one sub-air sac positioned outside the main air sac and filled with the floating gas. The sub-air sac is provided with a connection valve for connecting and separating the sub-air sac and the main air sac. In the airship, an internal pressure of the main air sac is higher than an internal pressure of the sub-air sac, and a variation in the volume relative to a change in the internal pressure of the sub-air sac is larger than a variation in the volume relative to the variation in the internal pressure of the main air sac.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This specification relates to airships, and in particular to non-rigid airships. [Background technology]

[0002] Patent Document 1 discloses an airship. This airship is equipped with a gas bag that stores buoyancy gas and multiple air bags that store air inside the air bag. With this configuration, the attitude of the airship can be controlled by adjusting the internal pressure of each air bag. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-93422 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, hydrogen has been attracting attention as a sustainable energy medium. To popularize hydrogen as an energy medium, it is necessary to develop an inexpensive production method that does not emit carbon dioxide, as well as an inexpensive means of transportation. As a method for large-scale transportation of hydrogen, in addition to transportation by pipeline, efforts are being made to liquefy hydrogen like natural gas and transport it by sea in specialized tankers.

[0005] However, liquefying hydrogen requires cooling it to approximately -253°C, and all ortho-hydrogen must be converted to para-hydrogen beforehand, which requires a large amount of energy. Furthermore, iron, the main material used in tankers, tends to become embrittled at low temperatures, and hydrogen permeates metals like iron, causing embrittlement. For this reason, building a tanker for liquid hydrogen requires more advanced technology and costs than building a tanker for liquefied natural gas.

[0006] From an economic standpoint, tankers can only achieve a transport speed of around 15 knots at most, making it impossible to respond quickly to demand. To realize a hydrogen society, the price of hydrogen must be reduced to less than half of its current price, and it will be difficult to meet this demand with a high-cost, slow-speed transport method like tankers.

[0007] The use of airships is considered as a new and useful means of transporting hydrogen. Airships are generally classified into non-rigid airships, semi-rigid airships, and rigid airships. Non-rigid airships use the air envelope itself as the hull and do not have a particular framework to ensure rigidity. In contrast, semi-rigid airships have a framework, and rigid airships have a rigid hull that stores the air envelope for lift.

[0008] Due to their simple structure, nonrigid airships account for the majority of airships in practical use today. To ensure rigidity, the hull is rugby-ball shaped, and a ballonette (air bladder) is used to pressurize the lift gas and adjust buoyancy and pitch angle (see Patent Document 1). Since the lift gas is typically expensive helium, the air inside the ballonette is pressurized to minimize its loss and ensure rigidity. Therefore, the air inside the ballonette and the helium lift gas are at equal pressure, which can easily lead to problems such as sloshing. Furthermore, the rigidity achieved in this way imposes limitations on the size and shape of the hull. To achieve larger sizes and higher speeds, semi-rigid airships with internal frameworks or rigid airships with rigid outer hulls and lift gas bladder ... Furthermore, even a 4% hydrogen content in air exceeds the explosive limit. Therefore, if a ballonette-type blimp is constructed using hydrogen as the lift gas, and hydrogen leaks into the ballonette through the diaphragm, the air inside the ballonette may be at risk of explosion. On the other hand, if hydrogen leaks into the open air, it is unlikely to reach the explosive limit because of the fast diffusion rate of hydrogen.

[0009] In light of the above, this specification discloses a new and useful airship. [Means for solving the problem]

[0010] The airship disclosed in this specification comprises a main air envelope filled with buoyancy gas, and at least one auxiliary air envelope located outside the main air envelope and filled with the buoyancy gas. The auxiliary air envelope is provided with a connection valve for connecting and isolating the auxiliary air envelope from the main air envelope. In this airship, the internal pressure of the main air envelope is higher than the internal pressure of the auxiliary air envelope, and the amount of change in volume of the auxiliary air envelope in response to a change in the internal pressure is greater than the amount of change in volume of the main air envelope in response to a change in the internal pressure.

[0011] In the above-described configuration, since the internal pressure of the main air sac is lower than that of the auxiliary air sac, the internal pressure of the auxiliary air sac can be increased by supplying buoyancy gas from the main air sac to the auxiliary air sac. Here, the volume change rate of the auxiliary air sac (the amount of change in volume relative to a change in internal pressure) is greater than that of the main air sac. Therefore, when buoyancy gas is supplied from the main air sac to the auxiliary air sac, the increase in volume of the auxiliary air sac is greater than the decrease in volume of the main air sac. This facilitates increasing the buoyancy of the airship. Because the auxiliary air sac is located outside the main air sac, its volume can freely change in response to the internal pressure of the main air sac, regardless of the internal pressure of the main air sac. Therefore, the internal pressure of the main air sac can be relatively high, thereby increasing the rigidity of the main air sac. Furthermore, increasing the rigidity of the main air sac also allows the main air sac to be larger. Furthermore, since the internal pressures of the main air sac and the auxiliary air sac are different from each other, problems such as sloshing are also suppressed.

[0012] For these reasons, the airship disclosed in this specification can be used as a means of transportation for transporting hydrogen as a payload. That is, in countries or regions that supply hydrogen, large amounts of hydrogen can be loaded onto an airship by filling the main air sac with hydrogen gas at high pressure. As an example, hydrogen gas has a very low specific gravity of 0.0695 relative to air, and its mass is equivalent to 1 / 14.4 of air. That is, when the main air sac is filled with hydrogen gas, the internal pressure of the main air sac reaches 14.4 atmospheres, and the density finally balances with the external air. Therefore, even if the internal pressure of the main air sac is 10 atmospheres or higher, buoyancy can be generated as long as the airship's own weight is sufficiently light.

[0013] An airship loaded with hydrogen from a hydrogen supplier can fly to a country or region that demands hydrogen by using the hydrogen as lift-off gas. At the hydrogen demand destination, the hydrogen gas used as lift-off gas can be unloaded as payload. At this time, the amount of hydrogen gas required as lift-off gas for the next flight to the supplier or another destination can be retained without being unloaded. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a side view showing a schematic diagram of an airship 10 according to Example 1. The direction UP in the figure indicates the upward direction in the vertical direction, and the direction DN in the figure indicates the downward direction in the vertical direction. The direction FR in the figure indicates the forward direction in the longitudinal direction, and the direction RR in the figure indicates the rearward direction in the longitudinal direction. The vertical direction is perpendicular to the longitudinal direction. [Figure 2] 1 is a diagram showing a cross section of sub-bladder 14 in Example 1, particularly showing the state in which connection valve 26 is in operation. A similar configuration is also employed in sub-bladder 114 in Example 2. [Figure 3] FIG. 1 is a diagram showing a cross section of a sub-air envelope 14 of the airship 10 of the first embodiment, particularly showing the state in which a pump 28 is operating. [Figure 4] FIG. 2 is a diagram showing a cross section of a sub-air envelope 14 in the first embodiment, particularly showing the state in which an exhaust valve 30 is in operation. [Figure 5] 1 is a diagram showing a cross section of the sub-air envelope 14 of the airship 10 of the first embodiment, particularly showing the state in which both the pump 28 and the exhaust valve 30 are operating. FIG. [Figure 6] 1 shows a state in which a drone 22 has been released from the airship 10 in flight in the airship 10 of the first embodiment. [Figure 7] 1 is a plan view schematically showing an airship 100 of Example 2. The direction LH in the figure indicates the left in the left-right direction, and the direction RH in the figure indicates the right in the left-right direction. The left-right direction is perpendicular to the up-down direction and the front-back direction. DETAILED DESCRIPTION OF THE INVENTION

[0015] In one embodiment of the present technology, the sub-bladder may be provided with a pump that pumps the buoyancy gas in the sub-bladder to the main bladder. With this configuration, the internal pressure of the sub-bladder can be reduced without discharging the buoyancy gas in the sub-bladder to the outside.

[0016] Additionally or alternatively, the auxiliary air bag may be provided with an exhaust valve for exhausting the buoyancy gas within the auxiliary air bag to the outside. This simple configuration allows the internal pressure of the auxiliary air bag to be reduced. The exhaust valve may be, but is not limited to, a flow control valve that adjusts the flow rate of the buoyancy gas exhaust, or a pressure control valve that exhausts buoyancy gas when the internal pressure of the auxiliary air bag exceeds a set pressure, and the set pressure may be adjustable.

[0017] In one embodiment of the present technology, the at least one sub-air envelope may include a plurality of sub-air envelopes. In this case, the plurality of sub-air envelopes may be arranged along the longitudinal direction of the main air envelope. With this configuration, the pitch angle of the main air envelope (i.e., the airship) can be controlled by adjusting the internal pressure of each of the plurality of sub-air envelopes. Note that the pitch angle here refers to the angle between the longitudinal direction of the main air envelope and the horizontal plane.

[0018] In one embodiment of the present technology, the volume of the main air sac may be larger than the volume of the sub-air sac. With this configuration, a sufficient amount of lift gas can be supplied from the main air sac to the sub-air sac. Furthermore, the larger the volume of the main air sac, the more hydrogen can be transported when the airship is used as a means of transporting hydrogen.

[0019] In one embodiment of the present technology, the internal pressure of the main bladder may be 1.2 atmospheres or more. In particular, when the lifting gas is hydrogen gas, the internal pressure of the main bladder may be 10 atmospheres or more. The higher the internal pressure of the main bladder, the higher the rigidity of the main bladder (i.e., the rigidity of the airship). Furthermore, when the airship is used as a means of transporting hydrogen, a larger amount of hydrogen can be transported.

[0020] In one embodiment of the present technology, the airship may further include a drone connected to the main air envelope for changing the direction of travel of the airship. With this configuration, even if the main air envelope is enlarged, the direction of travel of the airship can be easily changed.

[0021] In the above-described embodiment, the drone may be capable of carrying a person. In this case, the drone may be configured to be able to detach from the main air envelope while the airship is in flight. With this configuration, the airship passengers can use the drone to detach from the airship during flight as needed. [Example]

[0022] (Example 1) An airship 10 of Example 1 will be described with reference to the drawings. The airship 10 of this example is a so-called non-rigid airship and has a relatively simple configuration. As shown in FIG. 1, the airship 10 comprises a main air envelope 12 filled with buoyancy gas, and a plurality of sub-air envelopes 14 located outside the main air envelope 12 and filled with buoyancy gas. The buoyancy gas may be, for example, hydrogen gas or helium gas, although it is not particularly limited thereto.

[0023] The main air envelope 12 has a generally cylindrical shape and extends along the longitudinal directions FR and RR. That is, the longitudinal direction of the main air envelope 12 is parallel to the longitudinal directions FR and RR. The multiple sub-air envelopes 14 are arranged along the longitudinal direction of the main air envelope 12. The number of sub-air envelopes 14 is not particularly limited. As an example, the airship 10 of this embodiment has three sub-air envelopes 14a, 14b, and 14c. The three sub-air envelopes 14a, 14b, and 14c include a first sub-air envelope 14a located in the front of the main air envelope 12, a second sub-air envelope 14b located in the middle of the main air envelope 12, and a third sub-air envelope 14c located in the rear of the main air envelope 12. In other embodiments, the airship 10 may be provided with at least one sub-air envelope 14.

[0024] The main air envelope 12 is filled with buoyancy gas at a relatively high pressure, and the internal pressure of the main air envelope 12 is higher than the internal pressure of each of the sub-air envelopes 14. The specific gravity of hydrogen gas is very small at 0.0695, and its mass is 1 / 14.4 of that of air. Therefore, even if the internal pressure of the main air envelope 12 is 10 atmospheres or more, the main air envelope 12 can generate sufficient buoyancy relative to the weight of the airship 10 itself by using a material that is sufficiently lightweight, has gas barrier properties, and has the structural strength to withstand high pressure.

[0025] The sheet material that makes up the main bladder 12 has high rigidity against tensile forces (i.e., a high Young's modulus). Therefore, even when the main bladder 12 is filled with buoyancy gas at high pressure, the change in volume of the main bladder 12 is relatively small. In contrast, the sheet material that makes up each sub-bladder 14 has lower rigidity against tensile forces (i.e., a lower Young's modulus) than the sheet material that makes up the main bladder 12. Therefore, the amount of change in volume of each sub-bladder 14 in response to a change in internal pressure is greater than the amount of change in volume of the main bladder 12 in response to a change in internal pressure. Because the sheet material that makes up the main bladder 12 is also required to have gas barrier properties, it is considered to be a composite material or a multi-layered film made up of a member that meets structural strength requirements.

[0026] The main envelope 12 is provided with a propulsion unit 16 that generates thrust for the airship 10 and a plurality of tail fins 18 that stabilize the attitude of the airship 10. The propulsion unit 16, in part due to the slender shape of the main envelope 12, allows the airship 10 to fly at a relatively high speed. Although not particularly limited, the propulsion unit 16 in this embodiment is designed to achieve a speed of 75 knots or more. For this reason, the shape of the main envelope 12 may be designed to obtain dynamic lift.

[0027] The airship 10 further includes a container pod 20 and a drone 22. The container pod 20 can carry various payloads. Although not particularly limited, the container pod 20 is detachably connected to the main air envelope 12. The drone 22 is a so-called multicopter and can fly independently. The drone 22 is connected to the main air envelope 12 and can change the direction of travel of the airship 10, for example, like a tugboat on a ship.

[0028] The airship 10 further includes a control device 24. The control device 24 has a memory and a processor and is programmed to control the flight operation of the airship 10. Although not particularly limited, the control device 24 may be disposed in the drone 22. The control device 24 is communicatively connected to the propulsion units 16 and the tail units 18 wirelessly or via a wire, and can control the operation of the propulsion units 16 and the tail units 18. The control device 24 may control the operation of the propulsion units 16 and the tail units 18 in response to human operation. Alternatively, the control device 24 may wirelessly communicate with an external device disposed on the ground or the like and control the operation of the propulsion units 16 and the tail units 18 in response to commands from the external device. Alternatively, the control device 24 may autonomously control the operation of the propulsion units 16 and the tail units 18 based on its own judgment.

[0029] As shown in FIG. 2, the first sub-bladder 14a is provided with a connection valve 26, a pump 28, and an exhaust valve 30. The connection valve 26 is located in the partition between the main bladder 12 and the first sub-bladder 14a and can connect or disconnect the first sub-bladder 14a from the main bladder 12. That is, when the connection valve 26 is opened, the first sub-bladder 14a and the main bladder 12 are connected, and buoyancy gas is supplied from the main bladder 12 to the first sub-bladder 14a. As a result, the volume of the first sub-bladder 14a increases, and the buoyancy provided by the first sub-bladder 14a increases. The connection valve 26 is connected to the control device 24 wirelessly or by wire, and its operation is controlled by the control device 24. Similar connection valves 26 are provided not only in the first sub-bladder 14a but also in the second sub-bladder 14b and the third sub-bladder 14c. In addition, in Figures 2 to 5, for convenience, the main air bag 12 and the sub-air bag 14 are shown with a certain thickness, but the sheet material that makes them up is a membrane material that is as light and thin as possible structurally.

[0030] The pump 28 is located in the partition between the main bladder 12 and the first sub-bladder 14a and can pump the buoyancy gas in the first sub-bladder 14a into the main bladder 12. This allows the internal pressure of the first sub-bladder 14a to be reduced without discharging the buoyancy gas from the first sub-bladder 14a to the outside. As shown in FIG. 3, when the pump 28 is operated, the internal pressure of the first sub-bladder 14a is reduced. As a result, the volume of the first sub-bladder 14a decreases, and the buoyancy provided by the first sub-bladder 14a decreases. The pump 28 is connected to the control device 24 wirelessly or by wire, and the operation of the pump 28 is controlled by the control device 24. Similar pumps 28 are provided not only in the first sub-bladder 14a but also in the second sub-bladder 14b and the third sub-bladder 14c.

[0031] The exhaust valve 30 is located on the outer wall of the first sub-air bag 14a and can exhaust the buoyancy gas within the first sub-air bag 14a to the outside. That is, as shown in FIG. 4, when the exhaust valve 30 is opened, the buoyancy gas within the first sub-air bag 14a is exhausted to the outside. As a result, the volume of the first sub-air bag 14a decreases, and the buoyancy provided by the first sub-air bag 14a decreases. The exhaust valve 30 is connected to the control device 24 by wire or wirelessly, and the operation of the exhaust valve 30 is controlled by the control device 24. Similar exhaust valves 30 are provided not only in the first sub-air bag 14a but also in the second sub-air bag 14b and the third sub-air bag 14c.

[0032] 5, the control device 24 can also operate both the pump 28 and the exhaust valve 30 simultaneously. By operating both the pump 28 and the exhaust valve 30 simultaneously, the control device 24 can rapidly reduce the volume of the first sub-air bag 14a, thereby quickly reducing the buoyancy provided by the first sub-air bag 14a. Note that each sub-air bag 14 may be provided with only one of the pump 28 and the exhaust valve 30.

[0033] With the above configuration, the control device 24 can adjust the buoyancy of each sub-air envelope 14 by controlling the operation of the connection valve 26 and the pump 28 (and / or the exhaust valve 30) of each sub-air envelope 14. This allows the airship 10 to move up and down and adjust the pitch angle of the airship 10.

[0034] As shown in Figure 7, the drone 22 is configured to be able to detach from the main envelope 12 while the airship 10 is flying. In particular, the drone 22 in this embodiment is configured to be able to carry a person on board. This allows the person on board the airship 10 to detach from the airship 10 during flight by using the drone 22 as needed. Even in this case, the control device 24 mounted on the drone 22 can continue to control the flight of the airship 10 by communicating wirelessly with the airship 10.

[0035] In the airship 10 of this embodiment, the internal pressure of the main air envelope 12 is lower than the internal pressure of each sub-air envelope 14, so the internal pressure of each sub-air envelope 14 can be increased by supplying buoyancy gas from the main air envelope 12 to each sub-air envelope 14. Here, the volume change rate (amount of volume change with respect to change in internal pressure) of each sub-air envelope 14 is greater than the volume change rate of the main air envelope 12. Therefore, when buoyancy gas is supplied from the main air envelope 12 to each sub-air envelope 14, the increase in volume of each sub-air envelope 14 is greater than the decrease in volume of the main air envelope 12. This makes it easy to increase the buoyancy generated by the airship 10.

[0036] Because each sub-bladder 14 is located outside the main bladder 12, the volume of each sub-bladder 14 can freely change according to the internal pressure of the main bladder 12, regardless of the internal pressure of the main bladder 12. Therefore, the internal pressure of the main bladder 12 can be made relatively high, thereby increasing the rigidity of the main bladder 12. Increasing the rigidity of the main bladder 12 also allows the main bladder 12 to be made larger. Furthermore, because the internal pressures are different between the main bladder 12 and each sub-bladder 14, problems such as sloshing can be suppressed. Due to these new and useful features, the airship 10 of this embodiment can be used as a means of transporting hydrogen as a payload.

[0037] (Example 2) An airship 100 of Example 2 will be described with reference to the drawings. The airship 100 of Example 2 is equipped with two main air envelopes 112, which differs from the airship 10 of Example 1. The two main air envelopes 112 each extend in the longitudinal direction and are adjacent to each other in the lateral direction. Each main air envelope 112 is equipped with a thruster 16 and multiple tail fins 18. Multiple sub-air envelopes 114 are disposed between the two main air envelopes 112 and are arranged along the longitudinal direction of the two main air envelopes 112. The horizontal arrangement of the multiple main air envelopes 112 results in a shape that is more likely to generate dynamic lift, and by utilizing the ground effect caused by limiting flight altitude to a low altitude, it is possible to transport hydrogen at a higher pressure and in a larger volume.

[0038] The configuration and function of each main air envelope 112 in Example 2 are the same as those of the main air envelope 12 in Example 1. The configuration and function of each sub air envelope 114 in Example 2 are the same as those of each sub air envelope 14 in Example 1. Furthermore, the airship 100 in Example 2 may also be provided with a connection valve 26, a pump 28, and an exhaust valve 30, as in Example 1.

[0039] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives alone is technically useful. [Explanation of symbols]

[0040] 10, 100: Airship 12, 112: Main air sac 14, 114: Accessory air sac 16: Propulsion machine 18:Tail 20: Container Pod 22: Drone 24: Control device 26: Connection valve 28: Pump 30: Exhaust valve

Claims

1. a main envelope filled with lift gas; at least one sub-bladder located outside the main bladder and filled with the lifting gas; Equipped with the auxiliary air bag is provided with a connection valve for connecting and isolating the auxiliary air bag from the main air bag, the internal pressure of the main air sac is higher than the internal pressure of the sub-air sac; a change in volume of the sub-bladder in response to a change in the internal pressure is greater than a change in volume of the main bladder in response to a change in the internal pressure; airship.

2. 2. The airship according to claim 1, wherein the sub-air envelope is provided with a pump for pumping the buoyancy gas in the sub-air envelope to the main air envelope.

3. 3. The airship according to claim 1, wherein the sub-air envelope is provided with a discharge valve for discharging the buoyancy gas within the sub-air envelope to the outside.

4. the at least one sub-bladder includes a plurality of sub-bladder The airship according to claim 1 , wherein the plurality of sub-air envelopes are arranged along a longitudinal direction of the main air envelope.

5. 4. The airship according to claim 1, wherein a volume of the main air envelope is greater than a volume of the sub-air envelope.

6. 5. The airship according to claim 1, wherein the internal pressure of the main envelope is 1.2 atmospheres or more.

7. The airship according to claim 1 , wherein the airship has a plurality of main air envelopes.

8. The airship according to claim 1 , further comprising a drone connected to the main envelope for changing the direction of travel of the airship.

9. The airship according to claim 8 , wherein the drone is capable of carrying a person and is configured to be detachable from the main air envelope during flight of the airship.

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