Pipeline and fuel cell system with pipeline

Abstract

The invention relates to a duct (10) for a fuel cell system (100), in particular for a vehicle operated by means of the fuel cell system (100), for discharging exhaust air from the fuel cell system (100), comprising at least one fluid line (12) having an inlet (14) and an outlet (16), wherein the outlet (16) is designed to discharge the exhaust air into the environment, in particular below the waterline, in particular below the fording depth of the vehicle. In this context, a water discharge device (20) is arranged between the outlet (16) and the inlet (14) of the fluid line (12) for preventing accidental entry of water from the outlet (16) into the inlet (14), where the water discharge device (20) is connected in fluid communication to the at least one drain valve (22). The invention further relates to a fuel cell system (100) having a conduit (10).

Description

Technical Field

[0001] The invention relates to a line for a fuel cell system, in particular for a vehicle operated with a fuel cell system, for discharging exhaust air from the fuel cell system, and to a fuel cell system having a line. Background Art

[0002] DE 10 2012 010 131 A1 discloses a device for supplying educts or for discharging products of a fuel cell, comprising a pipeline, which comprises an area connected to a liquid source. In the intended use, this area connected to the liquid source via a liquid supply line is arranged below the parts of the pipeline upstream and downstream of the area in the flow direction. In this context, the area is implemented as a siphon in the pipeline.

[0003] US2012 / 0214079 A discloses a fuel cell system that inhibits water from flowing back from the outlet of the exhaust air pipe that discharges reactive exhaust gas without reducing the performance and fuel consumption of the fuel cell. In this context, the exhaust air pipe is configured so that it switches between the main exhaust pipe and the auxiliary exhaust pipe by a switching device to discharge reactive gas. The auxiliary outlet pipe includes an ascending gradient portion and a descending gradient portion, the ascending gradient portion is configured so that it tilts upward above the gradient of the main outlet pipe, and the descending gradient portion is configured so that it tilts downward downstream of the ascending gradient portion. The switching valve switches so that when the amount of the gas to be reacted is equal to or greater than the threshold value of the emission amount, it allows the gas to be reacted to be discharged from the main exhaust line, and when the amount of the gas to be reacted is below the threshold value of the emission amount, it allows the gas to be reacted to be discharged from the auxiliary exhaust line. Summary of the invention

[0004] The object of the present invention is to provide a conduit for a fuel cell system, in particular for a vehicle operated by a fuel cell system, for discharging exhaust air from a fuel cell system, which conduit prevents the risk of water flowing back into the fuel system.

[0005] A further object is to provide a fuel cell system having such a pipeline.

[0006] According to one aspect of the present invention, the above-mentioned object is solved by means of a conduit for discharging exhaust air from a fuel cell system, in particular for a vehicle operated by means of a fuel cell system, the conduit comprising at least one fluid line having an inlet and an outlet, wherein the outlet is configured to discharge the exhaust air into the environment, in particular below the waterline, in particular below the wading depth of the vehicle, wherein a water discharge device for preventing water from accidentally entering the inlet from the outlet is arranged between the outlet and the inlet of the fluid line, wherein the water discharge device is fluidically connected to at least one drain valve.

[0007] According to a further aspect of the invention, the further object is solved by a fuel cell system having a cathode supply air path and a cathode exhaust air path of a fuel cell unit and having at least one duct.

[0008] Advantageous embodiments and advantages of the invention emerge from the additional claims, the description and the drawings.

[0009] According to one aspect of the invention, a conduit for discharging exhaust air from a fuel cell system, in particular for a vehicle operated with the fuel cell system, is provided, comprising at least one fluid line having an inlet and an outlet, wherein the outlet is configured for discharging the exhaust air into the environment, in particular below the waterline, in particular below the wading depth of the vehicle. In this context, a water discharge device for preventing water from accidentally entering the inlet from the outlet is arranged between the outlet and the inlet of the fluid line, wherein the water discharge device is fluidically connected to at least one drain valve.

[0010] In this context, the duct can advantageously be installed in an exhaust air device of a fuel cell system, in particular a vehicle operated by means of the fuel cell system, in order to discharge the exhaust air of the fuel cell system from the turbine to the environment. When the outlet of the duct is arranged below the waterline, in particular below the wading depth of the vehicle, in particular when the vehicle is wading, there is a risk that water penetrates into the exhaust air system counter to the flow direction of the exhaust air and flows in the direction towards the turbine. In this way, components in the exhaust air system, and in particular in the turbine, can become permanently damaged.

[0011] The proposed pipeline comprises a water discharge device with at least one drain valve, which minimizes this risk, since the permeated water is, for example, directed into an overflow container of the water discharge device or is prevented by a siphon of the water discharge device from reaching the inlet of the pipeline with the turbine. The permeated water can be discharged from the overflow container or the siphon region via the at least one drain valve. In this way, a backflow of water into the fuel cell system can be advantageously avoided.

[0012] According to an advantageous embodiment of the pipeline, the acoustic damping device can be integrated in the water discharge device. The turbine that guides the exhaust air into the fluid line can generate a strong acoustic excitation of the exhaust air flow. With the help of the acoustic damping device, for example in the form of a Helmholtz resonator or a broadband damping device, the generated noise can be effectively attenuated. Due to the integration of the acoustic damping device into the water discharge device, installation space can be effectively saved. In addition, this can advantageously lead to cost savings compared to separate individual solutions.

[0013] According to an advantageous embodiment of the pipeline, at least one drain valve can be hydraulically connected to a pump for draining water. The permeated water can be drained from the pipeline via the drain valve. The water can be drained particularly effectively when the drain valve is connected to a pump that can suck away the water. Alternatively, the water can also be blown out through the drain valve.

[0014] According to an advantageous embodiment of the pipeline, a conveying device for supplying exhaust air into the fluid line can be arranged at or in the inlet. In particular, the conveying device can be a turbine. In a fuel cell system, the exhaust air is usually blown out by means of a turbine or another fluid conveying device. The turbine is usually integrated as part of the fuel cell system. As an alternative, the turbine can also be a component of the pipeline.

[0015] According to an advantageous embodiment of the pipe, the inlet and the outlet can be arranged to be vertically offset. In particular, in this context, the inlet can be arranged above the outlet in the direction of gravity. In this way, the inlet may already be partially protected from water backflow by the effect of gravity.

[0016] However, as an alternative, the inlet and outlet can also be arranged at the same level. In this case, higher requirements are placed on the water discharge device in terms of protecting the inlet of the fluid line from water backflow, especially in wading operations of the vehicle. In this context, a siphon tube provides a possibility as a water discharge device.

[0017] According to an advantageous embodiment of the pipeline, a water level sensor can be arranged in the fluid line, in particular spatially adjacent to the outlet, in particular at the level of the outlet. The water level sensor can additionally provide a signal that water has penetrated into the fluid line. In this way, for example, a pump for conveying water out of the drain valve can be actuated.

[0018] According to an advantageous configuration of the pipeline, the water discharge device can include an overflow container. In this context, the drain valve can be arranged in particular at the lowest point of the overflow container. In this way, the penetrating water can advantageously be first captured and then discharged through the drain valve. When the drain valve is arranged at the lowest point of the overflow container, the overflow container can be reliably emptied due to gravity after the waterline has dropped, in particular after the vehicle has finished wading. With the help of an additional pump at the drain valve, the water can also be discharged during wading.

[0019] According to an advantageous embodiment of the pipeline, the overflow container can include at least one resonator chamber, which is fluidically connected to the fluid line as an acoustic damping device for acoustically attenuating the exhaust air flow. In particular, in this context, the overflow container can be configured as a Helmholtz resonator. By means of this Helmholtz resonator, noise caused by the turbine and / or flow conduction can be effectively attenuated.

[0020] According to an advantageous configuration of the conduit, the overflow container can include a plurality of resonator chambers which are fluidically connected to the fluid line as an acoustic damping device for acoustically attenuating the exhaust air flow. In particular, in this context, the overflow container can be configured as a multi-chamber resonator. By means of a multi-chamber resonator, the noise caused by the turbine and / or the flow conduction can be attenuated particularly effectively at several frequencies and / or across a larger frequency range compared to a single-chamber resonator.

[0021] According to an advantageous embodiment of the pipeline, the overflow container can comprise a plurality of resonator chambers as acoustic damping devices, the resonator chambers being arranged at the same level and / or at different levels of the fluid line. In particular, in this context, the overflow container can be configured as a broadband damping device. By means of the broadband damping device, the noise caused by the turbine and / or the flow conduction can be attenuated particularly effectively across a wide frequency range.

[0022] According to an advantageous configuration of the pipeline, the resonator chamber can be arranged to surround the fluid line in a hollow cylindrical shape and can be connected to the fluid line in fluid communication via a wall opening. In this configuration, the broadband damping device can be arranged particularly effectively around the fluid line and can be connected in fluid communication with the fluid flow in the fluid line via individual wall openings. This arrangement is also known as a 360° damping device. For this arrangement, it is particularly advantageous when the pipeline includes a water discharge device, because the resonator chamber placed below the fluid line may become filled with water. For the proposed configuration, this situation can be advantageously prevented because the drain valve is arranged in the lower positioned resonator chamber.

[0023] According to an advantageous embodiment of the pipeline, the overflow valve can be arranged in the resonator chamber above the outlet. In addition, an additional drain valve can also be arranged at the higher positioned resonator chamber, so that water can be discharged again even there, for example, in the case of a rapid inflow of water that also reaches the higher positioned resonator chamber.

[0024] According to an advantageous embodiment of the pipeline, the water discharge device can be designed as a siphon and arranged to be integrated in the fluid line, wherein the upper edge of the siphon wall is positioned at a higher level than the installation level of the turbine in the fluid line. The siphon arrangement can effectively prevent that water backflow (for example, in the event of wading of a vehicle operated by means of the fuel cell system) can reach an inlet of the fluid line arranged at the same level as the outlet.

[0025] According to an advantageous embodiment of the pipeline, at least two siphons can be arranged one behind the other in the exhaust air flow direction. Arranging a plurality of siphons one behind the other in the fluid line can provide increased safety against water entering the turbine of the fuel cell system due to water backflow, in particular in the event of wading of a vehicle operated with the fuel cell system, because in the case of a plurality of siphons the water holding volume is correspondingly increased.

[0026] According to an advantageous embodiment of the pipeline, a plurality of resonator chambers of the resonator can be arranged as an acoustic damping device of the fluid line downstream of one or at least two siphons. Due to the plurality of resonator chambers, the noise generated by conduction of the turbine and / or the flow in the fluid line can be effectively attenuated in a wide frequency range.

[0027] According to an advantageous embodiment of the duct, the resonator chamber can be arranged to at least partially surround the fluid line and / or can be connected to the fluid line in fluid communication via a wall opening. By means of such a resonator chamber arrangement in which the resonator chamber surrounds the fluid line in a semicircular shape in cross section, the noise of the exhaust air flow can be advantageously attenuated over a wide frequency band. Such an arrangement is also referred to as a 180° damping device.

[0028] According to an advantageous embodiment of the pipeline, a drain valve can be arranged at one of the resonator chambers. In particular, in this context, the drain valve can be arranged at a level lower than the level of the upper edge of the siphon wall. In this way, it can be ensured that the infiltrated water can be discharged through the drain valve before reaching a critical level of the upper edge of the siphon wall.

[0029] According to a further aspect of the present invention, there is provided a fuel cell system having a cathode supply air path and a cathode exhaust air path of a fuel cell unit and having at least one pipe as described above.

[0030] The duct can advantageously be installed in an exhaust air device of a fuel cell system, in particular an exhaust air device of a vehicle operated by means of the fuel cell system, in order to discharge the exhaust air of the fuel cell system from the turbine to the environment. If the outlet of the duct is arranged below the waterline, in particular below the wading depth of the vehicle, there is a risk, in particular in the case of wading, that water penetrates into the exhaust air system counter to the flow direction of the exhaust air and flows in the direction of the turbine. As a result, components in the exhaust air system and in particular in the turbine can become permanently damaged.

[0031] The pipeline comprises a water discharge device with at least one drain valve, which minimizes this risk, since the permeated water is, for example, directed into an overflow container of the water discharge device or is prevented from reaching the inlet of the pipeline with the turbine due to a siphon of the water discharge device. The permeated water can be discharged from the overflow container or from the region of the siphon via the at least one drain valve. In this way, a backflow of water into the fuel cell system can be advantageously avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Further advantages are derived from the following description of the drawings. In the drawings, embodiments of the invention are illustrated. The drawings, the description and the claims contain many features in combination. A person skilled in the art will consider these features expediently and individually and combine them into expedient further combinations. In an exemplary manner:

[0033] Figure 1 is a schematic longitudinal section of a duct according to an embodiment of the invention for discharging exhaust air from a fuel cell system for a vehicle operated with a fuel cell system, the duct having an overflow container and a Helmholtz resonator;

[0034] Figure 2 is based on Figure 1 A schematic elevation view of a pipeline;

[0035] Figure 3 is a schematic longitudinal section of a pipeline according to a further embodiment of the invention having an overflow container and a multi-chamber resonator;

[0036] Figure 4 is based on Figure 3 A schematic elevation view of a pipeline;

[0037] Figure 5 is a schematic longitudinal section of a pipeline according to a further embodiment of the invention with an overflow container and a broadband damping device;

[0038] Figure 6 is based on Figure 5 A schematic elevation view of a pipeline;

[0039] Figure 7 is a schematic longitudinal section of a pipe according to a further embodiment of the invention having a siphon and a multi-chamber resonator;

[0040] Figure 8 is based on Figure 7 A schematic elevation view of a pipeline;

[0041] Fig. 9 is a schematic longitudinal section of a pipe according to a further embodiment of the invention having two siphons arranged one behind the other and a multi-chamber resonator;

[0042] Fig.10 is based on Fig. 9 a schematic elevation view of a pipeline; and

[0043] Fig.11 is a simplified illustration of a fuel cell system having a cathode supply air path and a cathode exhaust air path. DETAILED DESCRIPTION

[0044] In the drawings, the same reference numerals are used to identify the same or same type of components. The drawings show examples only and should not be construed as limiting.

[0045] Figure 1 A schematic longitudinal section of a duct 10 according to an embodiment of the invention for discharging exhaust air from a fuel cell system 100 for a vehicle operated with a fuel cell system 100 is shown, the duct being provided with an overflow container 30 and a Helmholtz resonator 32; Figure 2 In the figure, according to Figure 1 A schematic front view of the pipeline 10 is shown.

[0046] The conduit 10 includes a fluid line 12 having an inlet 14 and an outlet 16. The outlet 16 is configured to discharge exhaust air of the fuel cell system into the environment. The inlet 14 and the outlet 16 are arranged to be vertically offset. In particular, the inlet 14 is arranged above the outlet 16 along the gravity direction 60.

[0047] When installed in a vehicle, the outlet 16 can be arranged below the wading depth of the vehicle. For this reason, during a wading operation of the vehicle, water can penetrate into the fluid line 12 through the outlet 16 and possibly reach the inlet 14. In the fluid line 12, near the outlet 16, the penetrating water 84 is indicated by a symbol. The water inflow direction 82 is indicated by an arrow.

[0048] At or in the inlet 14, a delivery device 18 for supplying exhaust air into the fluid line 12 can be arranged, which is typically a turbine, such as Figure 1 and Figure 2 The exhaust air flow direction 80 is shown by arrows.

[0049] exist Figures 1 to 10 In the embodiment illustrated in , the turbine 18 is respectively illustrated as being integrated into the inlet 14 as part of the duct 10. However, the turbine 18 can also be arranged upstream of the duct 10 as part of the fuel cell system 100.

[0050] Water ingress into the turbine 18 and / or components (not shown) of the fuel cell system 100 disposed upstream may cause significant damage in the turbine and / or such components.

[0051] For this reason, a water drain device 20 is arranged between the outlet 16 and the inlet 14 of the fluid line 12 to prevent water from accidentally entering the inlet 14 from the outlet 16. The water drain device 20 is fluidically connected to at least one drain valve 22.

[0052] The water discharge device 20 comprises an overflow container 30. The drain valve 22 is arranged at the lowest point of the overflow container 30 relative to the illustrated gravity direction 60. To discharge the water, the drain valve 22 can additionally be hydraulically connected to a pump, by means of which the water can be sucked away. For this purpose, Figure 1 and Figure 2 The pump line 28 is indicated in the middle. The drain valve 22 can be formed, for example, as a conventional mushroom valve or a duckbill valve.

[0053] A water level sensor 24 is arranged in the fluid line 12 spatially adjacent to the outlet 16, in particular at the level of the outlet 16. The water level sensor 24 can additionally deliver a signal that water has penetrated into the fluid line 12. In this way, for example, a pump for draining water from the drain valve 22 can be activated.

[0054] Furthermore, an acoustic damping device 50 is integrated in the water discharge device 20. For this purpose, the overflow container 30 comprises at least one resonator chamber 38, which is fluidically connected to the fluid line 12 for acoustically damping the exhaust air flow. In particular, the overflow container 30 can thus be embodied as a Helmholtz resonator 32.

[0055] The overflow container 30 thus fulfils several functions. On the one hand, it contains water that flows back into the outlet 16 in the event of wading of the vehicle and discharges the water again via the drain valve 22. In addition, the upper region of the overflow container 30 acts as an acoustic damping device 50, since the resonator chamber 38 leading to the fluid line 12 is arranged here. Due to the integration of the water discharge device 20 and the acoustic damping device 50, a compact configuration of the pipeline 10 can be achieved and, advantageously, installation space and costs are saved.

[0056] Figure 3 A schematic longitudinal section of a pipeline 10 according to a further embodiment of the invention is shown with an overflow container 30 and a multi-chamber resonator 34; and Figure 4 In the figure, according to Figure 3 A schematic front view of the pipeline 10 is shown.

[0057] The function of the water discharge device 20 is to Figure 1 and Figure 21. The overflow container 30, however, comprises a plurality of resonator chambers 38, which are fluidically connected to the fluid line 12 for acoustically attenuating the exhaust air flow. The overflow container 30 is thus embodied as a multi-chamber resonator 34. The resonator chambers 38 can be formed, for example, as λ / 4 tubes for different frequencies. One resonator chamber 38 is arranged below the level of the outlet 16. The drain valve 22 is advantageously arranged in this resonator chamber 38, as the lowest point of the pipeline 10.

[0058] A water level sensor 24 is disposed in the fluid line 12 near the outlet 16 .

[0059] exist Figure 5 In FIG. 1 , a schematic longitudinal section of a pipeline 10 according to a further embodiment of the invention is shown, which has an overflow container 30 and a broadband damping device 36; and in FIG. Figure 6 In the figure, according to Figure 5 A schematic front view of the pipeline 10 is shown.

[0060] In this embodiment, the overflow container 30 includes a plurality of resonator chambers 38, which are arranged at the same level and / or different levels of the fluid line 12. The resonator chambers 38 include different sizes. Some resonator chambers 38 are arranged to surround the fluid line 12 in a hollow cylindrical shape and are connected to the fluid line 12 in fluid communication via the wall openings 21. The wall openings 21 can be designed to have a small diameter. In this context, each resonator chamber 38 is connected to the fluid line 12 in fluid communication via several wall openings 21. In this context, some resonator chambers 38 are arranged below the level of the outlet 16 because the resonator chambers 38 surround the fluid line 12 in a hollow cylindrical shape. The drain valve 22 is arranged in one of the lowest resonator chambers 38. The overflow container 30 is advantageously configured as a broadband damping device 36.

[0061] A further valve may advantageously be arranged as an overflow valve 26 above the outlet 16 in order thus to also discharge water which has penetrated up to the upper resonator chamber 38 of the overflow container 30 to the overflow pipe 27 .

[0062] Here, the water level sensor 24 is arranged further inwards in the fluid line 12 , but at the level of the outlet 16 .

[0063] Figure 7 A schematic longitudinal section of a pipe 10 according to a further embodiment of the invention is shown with a siphon 40 and a multi-chamber resonator 46; and Figure 8 Show according to Figure 7 A schematic front view of the pipeline 10 is shown.

[0064] In this embodiment, the water discharge device 20 is integrated as a siphon 40 in the fluid line 12. The inlet 14 and the outlet 16 of the fluid line 12 are arranged at the same level. The upper edge 44 of the siphon wall 42 of the siphon 40 is located at a level 45 higher than the installation level 19 of the turbine 18 in the fluid line 12. In this way, water 84 that has penetrated through the outlet 16 can be prevented from reaching the inlet 14, at least until it rises above the level of the upper edge 44.

[0065] A plurality of resonator chambers 38 of a resonator 46 are arranged as an acoustic damping device 50 at the fluid line 12, downstream of the siphon 40. The resonator chambers 38 surround the fluid line 12 in a semicircular shape in cross section and are fluidically connected to the fluid line 12 via the wall opening 21. With this so-called 180° damping device, a broadband attenuation of the generated noise of the exhaust air flow can be achieved.

[0066] The drain valve 22 is arranged at one of the resonator chambers 38, namely advantageously at a level 48 which is lower than the level 45 of the upper edge 44 of the siphon wall 42. In this way, the permeated water can be advantageously drained.

[0067] Fig. 9 A schematic longitudinal section of a pipe 10 according to a further embodiment of the invention is shown with two siphons 40 and a multi-chamber resonator 46 arranged one behind the other; Fig.10 In the figure, according to Fig. 9 A schematic front view of the pipeline 10 is shown.

[0068] In this embodiment, two siphons 40 are arranged one after another in the exhaust air flow direction 80. With this arrangement, water that has flowed across the upper edge 44 of the first siphon wall 42 can be prevented from reaching the inlet 14 having the turbine 18 by the second siphon 40.

[0069] The arrangement of the acoustic damping device 50 corresponds to Figure 7 and Figure 8 The embodiment illustrated in FIG.

[0070] Fig.11 A simplified illustration of a generally known fuel cell system 100 is shown, which has a fuel cell unit 120 with a cathode supply air path 122 and a cathode exhaust air path 124. Via the cathode supply air path 122, the fuel cell unit 120 is supplied with ambient air, which is filtered by the cleaning stage 102 and sucked in and compressed by the compressor of the turbocharger 110. The compressed air is cooled in the heat exchanger 104 and provided with a defined humidity by the humidifier 106.

[0071] In the fuel cell unit 120, oxygen from the air reacts with hydrogen to produce water, which is discharged from the fuel cell unit 120 as an air / water mixture via the cathode exhaust air path 124. The cathode exhaust air can transfer a portion of the water in the humidifier 106 to the cathode supply air. The water separator 108 is connected downstream of the humidifier 106. The separated water is discharged in the drainage path 130, and the dried cathode exhaust air is supplied to the turbine 18 of the turbocharger 110. It is particularly beneficial to position the water separator 108 upstream of the turbine of the turbocharger 110. An additional water separator 108 is arranged in the fuel cell system 100.

[0072] Via the line 10, the exhaust air is discharged from the turbine 18 of the turbocharger 110 into the environment. In this context, an additional water separator can optionally be integrated into the line 10. Figures 1 to 10 As described in the embodiment illustrated in , the pipeline 10 may include a water discharge device 20 that prevents water from flowing back into the turbine 18. In addition, the pipeline 10 may include an acoustic damping device 50 as described above, which achieves effective reduction of noise caused by the turbine 18 and / or flow conduction.

[0073] Reference numerals list

[0074] 10 Pipeline

[0075] 12 Fluid pipelines

[0076] 14 Entrance

[0077] 16 Exit

[0078] 18 Turbine

[0079] 19 Turbine installation level

[0080] 20 Water discharge equipment

[0081] 21 Wall opening

[0082] 22 Drain valve

[0083] 24 Water level sensor

[0084] 26 Relief valve

[0085] 27 Overflow pipe

[0086] 28 Pump line

[0087] 30 Overflow container

[0088] 32 Helmholtz resonator

[0089] 34 Multi-chamber resonator

[0090] 36 Broadband Damping Device

[0091] 38 Resonator Chamber

[0092] 40 Siphon

[0093] 42 Siphon wall

[0094] 44 Top edge

[0095] 45 Levels

[0096] 46 Resonator

[0097] 48 levels

[0098] 50 Acoustic Damping Equipment

[0099] 60 Gravity direction

[0100] 80 Exhaust air flow direction

[0101] 82 Water inflow direction

[0102] 84 Water

[0103] 100 Fuel Cell Systems

[0104] 102 Clean Grade

[0105] 104 Heat exchanger

[0106] 106 Humidifier

[0107] 108 Water separator

[0108] 110 Turbocharger

[0109] 120 Fuel Cell

[0110] 122 Cathode supply air path

[0111] 124 Cathode exhaust air path

[0112] 130 Drainage lines

Claims

1. A conduit (10) for discharging exhaust air from a fuel cell system (100), the conduit (10) comprising: a fluid line (12) comprising an inlet (14) and an outlet (16) configured to discharge the exhaust air into the environment; a turbine (18) arranged at or in the inlet (14) and configured to supply the exhaust air into the fluid line (12); a water discharge device (20) disposed between the outlet (16) and the inlet (14) and configured to prevent water from accidentally entering the inlet (14) from the outlet (16); and a drain valve (22) fluidly connected to the water discharge device (20), Therein, the water discharge device (20) comprises a siphon (40), the siphon (40) comprising a siphon wall (42), the upper edge (44) of the siphon wall (42) being positioned at a level (45) higher than the installation level (19) of the turbine (18).

2. The pipeline (10) according to claim 1, wherein The drain valve (22) is hydraulically connected to a pump for draining water.

3. A pipe (10) according to any one of the preceding claims, wherein: The siphon tube (40) includes a plurality of siphon tubes (40) arranged one after another along the exhaust air flow direction (80).

4. The pipe (10) according to any of the preceding claims, further comprising a resonator (46) as an acoustic damping device (50), the resonator (46) comprising a plurality of resonator chambers (38) arranged downstream of the siphon (40) along the fluid line (12).

5. The pipeline (10) according to claim 4, wherein: The plurality of resonator chambers (38) are arranged to at least partially surround the fluid line (12) and are fluidically connected to the fluid line (12) via a plurality of wall openings (21).

6. A pipeline (10) according to claim 4 or 5, wherein: The drain valve (22) is arranged at one of the plurality of resonator chambers (38) and at a level (48) lower than the level (45) of the upper edge (44) of the siphon wall (42).

7. A fuel cell system (100), comprising: A fuel cell unit (120); a cathode supply air path (122) of the fuel cell unit (120); a cathode exhaust air path (124) of the fuel cell unit (120); and A pipe (10) as claimed in any one of the preceding claims.

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