A tank designed to contain a gas under pressure.

Abstract

This tank (2) intended to contain a gas under pressure comprises: - an internal volume (4) for storing a gas under pressure, called the "internal volume of the tank", - a heating element (12) provided within the internal volume of the tank (4), - a temperature sensor (14) provided within the internal volume of the tank (4), and - a protective element (16) for the temperature sensor (14) provided within the internal volume of the tank (4), between the heating element (12) and the temperature sensor (14). Figure 2 (for abbreviations)

Description

Title of the invention: Tank for containing a pressurized gas

[0001] The invention relates to the field of pressure vessels, particularly for a vehicle. More specifically, the invention relates to a tank intended to contain a gas under pressure and a vehicle comprising such a tank.

[0002] A tank designed to contain a pressurized gas can be equipped with several accessories that perform various functions within the tank. In the case of a hydrogen (H2) storage tank, which is intended for use by a vehicle in which the tank is mounted to produce energy for vehicle propulsion, the tank may include a heating element designed to heat the hydrogen under certain conditions. For example, when the tank is emptied, the temperature inside the tank drops due to the pressure variation within the tank. This temperature may drop so low that a tank wall and / or internal seals become mechanically weakened. Such weakening can damage the tank and may cause a gas leak, which must be avoided.It is known that the heating element activates when the temperature inside the tank falls below a predetermined threshold value in order to prevent damage to the tank wall and / or the seals inside the tank. To this end, the tank is also equipped with a temperature sensor to measure the temperature inside the tank.

[0003] While the heating element and temperature sensor enable temperature control inside the tank, these components can nevertheless present a reliability issue. Indeed, when the heating element heats the tank wall and / or the gas inside the tank, it can also heat the temperature sensor, thereby distorting the temperature measurement taken by the sensor. The temperature sensor may thus provide a temperature reading that is higher than the actual temperature of the gas in the tank, which poses a risk to the integrity of the tank wall and / or the integrity of the seals inside the tank. This risk is amplified by the fact that, generally, when the heating element is of the radiant type, such a heating element effectively heats the tank wall but also significantly heats the temperature sensor.

[0004] The invention aims in particular to remedy these problems by improving the reliability of the temperature measurement of the gas in the tank when the latter is equipped with a heating element.

[0005] For this purpose, the invention provides a reservoir for containing a pressurized gas, comprising:

[0006] - an internal storage volume of a gas under pressure called the "internal volume of the reservoir ",

[0007] - a heating element provided within the internal volume of the tank,

[0008] - a temperature sensor provided within the internal volume of the tank, and

[0009] - a temperature sensor protection device provided in the internal volume of the tank, between the heating element and the temperature sensor.

[0010] Thus, the protective device protects the temperature sensor from the heating element, preventing it from being directly heated by the heating element, or at least mitigating this direct heating. Consequently, the temperature measured by the temperature sensor is more representative of the actual gas temperature in the tank. This improves the reliability of the gas temperature measurement in the tank when the heating element is present.

[0011] According to a preferred embodiment, the tank is intended to contain hydrogen under pressure and to be carried in a vehicle, such as a motor vehicle, a truck, a bus, a train, a machine, in particular a construction machine, or even a boat.

[0012] Advantageously, the temperature sensor is located at a distance from the protective device.

[0013] This expression means that the temperature sensor is not in contact with the protective device. This ensures that direct contact between the temperature sensor and the protective device is not permitted, as such contact could promote heat exchange between the temperature sensor and the protective device and thus distort the measurement of the temperature of the gas contained in the tank.

[0014] Advantageously, the reservoir further comprises at least one nozzle attached to the reservoir, the temperature sensor and the protective element being fixed to the nozzle.

[0015] A tank intended to contain a gas under pressure is often equipped with such an end fitting, so that the temperature sensor and the protective device can be easily fixed in the tank without having to provide an additional part specifically dedicated to this purpose.

[0016] Advantageously, the protective element is made of a material capable of withstanding temperatures between -60°C and 85°C.

[0017] This ensures that the protective device remains operational regardless of the temperature inside the tank.

[0018] Advantageously, the protective element is made of a material having a reflectivity p, a transmissivity r and an absorptivity a such that the sum p + r + a is equal to 1, and that r is less than the sum p + a.

[0019] Advantageously, the protective element is made of a material having an emissivity less than or equal to 0.03.

[0020] The protective device thus does not form a secondary heat source which would transmit heat to the temperature sensor, which transfer would distort the measurement of the temperature of the gas contained in the tank.

[0021] Advantageously, the protective device comprises:

[0022] - at least one shield arranged between the heating element and the sensor temperature, and

[0023] - at least one support element connecting, directly or indirectly, the minus one shield at least one tip.

[0024] The protective device is thus made in a simple form, so that it is inexpensive and easy to arrange in the tank.

[0025] Advantageously, at least one shield has a cone shape, a dome shape or a truncated cone shape having a convex part oriented towards the heating element.

[0026] The heat waves directed towards the protective device are thus reflected by the shield in several directions, mainly onto the wall of the tank.

[0027] According to one embodiment, at least one shield has a disc shape, the disc defining a first half-space in which the temperature sensor extends and a second half-space in which the heating element extends.

[0028] The shield is therefore particularly simple to make.

[0029] Advantageously, the protective element comprises several shields, preferably arranged coaxially.

[0030] This improves the thermal protection conferred by the protective element for the temperature sensor with respect to the heating element by obtaining an insulating effect comparable to that of double glazing.

[0031] According to a first embodiment of the invention, the protective device comprises several support elements in the form of 'n' pillars distributed around the temperature sensor, 'n' being an integer greater than or equal to one, preferably 'n' being equal to three.

[0032] According to a second embodiment of the invention, the support element forms a cylindrical grid surrounding the temperature sensor.

[0033] This ensures that the gas can circulate easily in the protective device and around the temperature sensor, which helps to make the measurement of the gas temperature in the tank more reliable.

[0034] Advantageously, the internal volume of the tank is delimited by a liner. Preferably the liner is made of plastic.

[0035] The invention can thus be easily implemented in so-called "Type III" and "Type IV" tanks. Without such a liner, the invention can be easily implemented in so-called "Type V" tanks.

[0036] The invention also provides for a vehicle comprising a tank as defined above. The term "vehicle" means any vehicle, such as a motor vehicle, truck, bus, train, machine, in particular construction equipment, or boat. Brief description of the figures

[0037] The invention will be better understood upon reading the following description, given solely by way of example and made with reference to the accompanying drawings in which:

[0038] [Fig. 1] is a schematic view of a vehicle, comprising a tank intended to contain a pressurized gas, according to the invention,

[0039] [Fig.2] is a cross-sectional view of a tank intended to contain a gas under pressure according to an embodiment of the invention,

[0040] [Fig.3] is a perspective view of a protective element for the tank of [Fig.2], according to a first embodiment of the invention,

[0041] [Fig.4] is a perspective view from a different angle of the protective organ of the [Fig.3],

[0042] [Fig. 5] is a perspective view of a protective device according to a variant of the first embodiment of the invention, and

[0043] [Fig.6] is a perspective view of a tank protection device of [Fig.2], according to a second embodiment of the invention. Detailed description

[0044] Figure 1 shows a vehicle 1 according to the invention. The vehicle 1 includes a tank 2 (arbitrarily positioned on the vehicle diagram) intended to contain a pressurized gas. The gas is intended to be used by the vehicle to perform a predefined function. In this case, the tank 2 is intended to contain hydrogen, which serves as the energy source for the propulsion of the vehicle 1.

[0045] Tank 2 is shown in more detail in [Fig. 2]. Tank 2 comprises an internal storage volume for a pressurized gas, which in this case is hydrogen, as indicated above. In what follows, this volume is referred to as the internal volume of tank 4, or simply internal volume 4. The volume The internal space 4 is delimited by a wall 6 of the tank. Wall 6 here comprises a liner, preferably made of plastic, but the liner can be replaced by any other type of wall suitable for storing gas under pressure. The tank 2 has a central portion generally shaped like a cylinder of revolution and two end portions generally shaped like domes that close the cylinder forming the central portion. The tank 2 thus has a principal axis 8, coinciding with the axis of revolution of the central portion and passing through the center of each of the two end portions.

[0046] The reservoir 2 includes at least one nozzle 10 formed in the center of one or the other of the two end portions. The nozzle 10 serves, for example, as a coupling interface with a pipe (not shown) allowing the filling and / or emptying of the reservoir 2. Here, the reservoir 2 includes two nozzles 10, each end portion receiving one of the two nozzles 10.

[0047] The tank 2 includes a heating element 12 provided within the internal volume 4 and configured to heat the wall of the tank 2 and / or the pressurized gas contained within the internal volume 4. This is a radiative heating element. The tank 2 further includes a temperature sensor 14 provided within the internal volume 4. If the gas is hydrogen, when the hydrogen is discharged from the tank 2, for example to power a fuel cell or the engine of the vehicle 1, the temperature drops inside the tank 2. To prevent this temperature from dropping too low to the point of damaging the wall 6 of the tank 2 and / or the seals (not shown) arranged inside the tank 2, the heating element 12 is activated, for example, when the temperature measured by the temperature sensor 14 falls below a predetermined threshold value.Here, the heating element 12 is fixed to one of the ends 10, while the temperature sensor 14 is fixed to the other end 10. Thus, the heating element 12 and the temperature sensor 14 are located in opposite and distant positions within the internal volume 4 along the main axis 8, as shown in [Fig.2].

[0048] The reservoir 2 includes a protective element 16; 16' for the temperature sensor 14 provided within the internal volume 4. The protective element 16; 16' is provided between the heating element 12 and the temperature sensor 14, and is attached to the same fitting 10 as the temperature sensor 14. The protective element 16; 16' has a shape such that no point of the heating element 12 can see a point of the temperature sensor 14, or at least cannot see a point of a measuring surface of the temperature sensor 14. In other words, it is not possible to draw a straight line connecting a point of the heating element 12 and a point of the temperature sensor 14 (or at least a point of the measuring surface of the sensor). temperature 14) without this line being interrupted by the protective element 16; 16'. This ensures that, thanks to the protective element 16; 16', the heating element 12 cannot directly heat the temperature sensor 14 (or at least its measuring surface).

[0049] The protective element 16; 16' has several general characteristics. The temperature sensor 14 is located at a distance from the protective element 16; 16', meaning that there is no contact surface between the protective element 16; 16' and the temperature sensor 14. The protective element 16; 16' is made of a material capable of withstanding temperatures between -60°C and 85°C, in the sense that it hardly deforms or deteriorates within this temperature range. The protective element 16; 16' is made of a material having a reflectivity p, a transmissivity r, and an absorptivity a such that the sum p + r + a is equal to 1, and r is less than the sum p + a. This ensures that the protective element 16; 16' does not form a secondary heat source that would transmit heat, produced by the heating element 12, to the temperature sensor 14.It can also be provided that the protective element 16; 16' is made of a material having an emissivity less than or equal to 0.03, for the same reason. The protective element 16; 16' comprises at least one shield 18, arranged between the heating element 12 and the temperature sensor 14, and at least one support element 20 connecting, directly or indirectly, the at least one shield 18 to the end fitting 10 to which the protective element 16; 16' is attached.

[0050] Figure 3 shows a protective element 16 according to a first embodiment. This protective element 16 comprises a shield 18 having a cone shape with a convex portion oriented towards the heating element 12. In other words, the tip of the cone is oriented towards the heating element 12, while the temperature sensor 14 extends from the concave side of the shield 18. However, this cone shape can be replaced by a dome shape or a frustoconical shape, these shapes also having a convex side and a concave side.

[0051] The protective element 16 of [Fig. 3] comprises several support elements 20 in the form of n pillars distributed, preferably regularly, around the temperature sensor 14, n being an integer greater than or equal to one, here equal to three. The pillars each have a generally cylindrical shape, one end of which is fixed to the nozzle 10 and the other end is fixed to the shield 18 or joined to the shield 18.

[0052] Figure 4 shows the protective element 16 of Figure 3 at a different angle, which illustrates the general characteristic whereby the temperature sensor 14 is located at a distance from the protective element 16. Indeed, it can be observed that on this [Fig.4] that there is no contact surface between, on the one hand, the temperature sensor 14 and, on the other hand, the shield 18 and the support elements 20.

[0053] Figure 5 shows a protective element 16 according to an alternative embodiment of the first embodiment. This protective element 16 differs from that of Figures 3 and 4 only in that the shield 18 has a disc shape, the disc defining a first half-space in which the temperature sensor 14 extends and a second half-space in which the heating element 12 extends.

[0054] Figure 6 shows a protective element 16' according to a second embodiment. This protective element 16' comprises two shields 18', each dome-shaped with a convex portion facing the heating element 12. In other words, the apexes of the domes face the heating element 12, while the temperature sensor 14 extends from the concave side of the shields 18'. However, these dome-shaped shields 18' can be replaced by cone-shaped or frustoconical shields, these shapes also having a convex and a concave side. The shields 18' are connected to each other by means of rods 22 parallel to the main axis 8. The shields 18' are arranged coaxially, meaning that, since each shield 18' defines a central axis, these axes coincide.

[0055] The protective element 16' of [Fig.6] includes a support element 20' in the form of a grid surrounding the temperature sensor 14. The support element 20' has the shape of a cylinder of revolution, one end of which is fixed to the end piece 10 to which the temperature sensor 14 is attached, and the other end is fixed to one of the shields 18' or made of the same material as it.

[0056] The invention is not limited to the embodiments shown and other embodiments will be obvious to a person skilled in the art.

[0057] It is possible to combine the different embodiments of the protective devices with each other, in particular with regard to the characteristics relating to the number of shields, the number of support elements, the shape of the shield(s), the shape of the support element(s). List of references

[0058] 1: vehicle

[0059] 2: reservoir

[0060] 4: internal volume

[0061] 6: wall

[0062] 8: main axis

[0063] 10: nozzle

[0064] 12: heating element

[0065] 14: temperature sensor

[0066]

[0067]

[0068]

[0069] 16; 16': protective element 18; 18': shield 20; 20': support element 22: rod

Claims

Demands

1. Tank (2) intended to contain a gas under pressure, characterized in that it comprises: - an internal volume (4) for storing a gas under pressure called the "internal volume of the tank", - a heating element (12) provided in the internal volume of the tank (4), - a temperature sensor (14) provided in the internal volume of the tank (4), and - a protection element (16; 16') for the temperature sensor (14) provided in the internal volume of the tank (4), between the heating element (12) and the temperature sensor (14).

2. Reservoir (2) according to the preceding claim, in which the temperature sensor (14) is located at a distance from the protective member (16; 16').

3. Reservoir (2) according to any one of the preceding claims, further comprising at least one nozzle (10) integral with the reservoir (2), the temperature sensor (14) and the protective element (16; 16') being fixed to the nozzle (10).

4. Reservoir (2) according to any one of the preceding claims, in which the protective element (16; 16') is made of a material capable of withstanding temperatures between -60°C and 85°C.

5. Reservoir (2) according to any one of the preceding claims, wherein the protective element (16; 16') is made of a material having a reflectivity p, a transmissivity r and an absorptivity a such that the sum p + r + a is equal to 1, and r is less than the sum p + a.

6. Tank (2) according to any one of the preceding claims, wherein the protective element (16; 16') is made of a material having an emissivity less than or equal to 0.

03.

7. A reservoir (2) according to at least claim 3, wherein the protective element (16; 16') comprises: - at least one shield (18; 18') arranged between the heating element (12) and the temperature sensor (14), and - at least one support element (20; 20') connecting, directly or indirectly, at least one shield (18; 18') to at least one end piece (10).

8. Reservoir (2) according to claim 7, in which at least one shield (18; 18') has a cone shape, a dome shape or a frustoconical shape having a convex part oriented towards the heating element (12).

9. Reservoir (2) according to claim 7, in which at least one shield (18; 18') has a disc shape, the disc defining a first half-space in which the temperature sensor (14) extends and a second half-space in which the heating element (12) extends.

10. Tank (2) according to any one of claims 7 to 9, wherein the protective element (16') comprises several shields (18'), preferably arranged coaxially.

11. Reservoir (2) according to any one of claims 7 to 10, wherein the protective element (16) comprises several support elements (20) in the form of 'n' pillars distributed around the temperature sensor (14), 'n' being an integer greater than or equal to one, preferably 'n' being equal to three.

12. Reservoir (2) according to any one of claims 7 to 10, wherein the support element (20') forms a cylindrical grid surrounding the temperature sensor (14).

13. Tank (2) according to any one of the preceding claims, wherein the internal volume of the tank (4) is delimited by a liner, preferably the liner is made of plastic material.

14. Vehicle (1) comprising a tank (2) according to any one of the preceding claims.