WO2022263180A1

WO2022263180A1 - Heat exchanger

Info

Publication number: WO2022263180A1
Application number: PCT/EP2022/064950
Authority: WO
Inventors: Richard BRÜMMER; Frank von Lützau; Jan Schultes; Thomas Strauss
Original assignee: Mahle International Gmbh
Priority date: 2021-06-14
Filing date: 2022-06-01
Publication date: 2022-12-22
Also published as: DE102021206021A1

Abstract

The invention relates to a heat exchanger (1) for a fuel cell system (2) with an upper header tank (4) and a lower header tank, between which are arranged upright tubes (5) which are accommodated tightly at their upper end in associated openings (6) in a first tube plate (7). In order to achieve improved cooling, at least one duct (9) for distributing water is provided on an outer lateral surface (8) of at least one tube (5), and, below the first tube plate (7), there is a distributor (10) which is fluidically connected to the at least one duct (9) of the at least one tube (5).

Description

heat exchanger

The present invention relates to a heat exchanger for a fuel cell system with an upper header tank and a lower header tank. The invention also relates to a motor vehicle with such a fuel cell system.

Compared to conventional engine cooling of an internal combustion engine, cooling of a fuel cell has to do significantly more. At lower process temperatures, significantly higher amounts of energy have to be dissipated via a coolant, since damage can occur even if the permissible maximum temperature is only slightly exceeded. In general, with essentially the same driving performance in a motor vehicle operated with a fuel cell, up to twice the amount of energy must be calculated as waste heat and must be dissipated via a coolant cooler. Combined with a coolant temperature required in a fuel cell system that is approx. 10 to 15 °C lower, corresponding increases in performance can only be achieved with larger coolant coolers or generally only with larger heat exchangers. An increase in cooling capacity via a higher cooling air flow in turn requires disproportionately more drive power in a fan, whereby due to a lack of mechanical coupling with a crankshaft in a fuel cell vehicle an electric motor has to be used, which in turn consumes significantly more electrical energy for the higher cooling air flow , which has a negative effect on the available vehicle range. In both cases it also applies that facto- such as a limited installation space, a limited weight, a given design and also the manufacturing costs, place narrow limits on increased or more powerful heat exchangers.

In order, for example, to achieve increased cooling capacity in heat exchangers known from the prior art, it is therefore known to use direct cooling of the heat exchanger by applying sprinkler water and generating an evaporation effect.

DE 102008051 368 A1 discloses a cooling system for transferring a heat flow from a heat source to a heat sink formed by an air flow with a closed coolant circuit, the closed coolant circuit introducing heat into the coolant circuit in heat-transferring connection with the heat source first heat exchanger and a second heat exchanger that is in heat-transferring connection with the heat sink and discharges heat from the coolant circuit, as well as an adiabatic or evaporation stage with at least one evaporation water in the air humidifier that forms the heat sink and introduces the air flow.

DE 19637926 A1 discloses a cooling device for an intercooler with a liquid container for storing a cooling liquid and a spraying device arranged in the vicinity of the cooling device, which has a pump with a pump line for transporting the cooling liquid to the spraying device. If required, water is sprayed onto a front surface of a charging air cooler in the direction of travel of the motor vehicle via a pipe and nozzles. However, the spray device requires a comparatively complex and multi-part attachment. A similar spray device is known from DE 2358631 A1, by means of which an air flow flowing through a cooling device can be subjected to sprinkler water. A pump, a reservoir and nozzles are also provided here, which are intended to enable finely divided injection of the sprinkler water into the air flow. However, fixing the nozzles is also complex.

DE 11 2007001 422 B4 discloses a cooler with a thermal transmission component with a main surface to be sprayed with a cooling fluid, the thermal transmission component comprising the following components: a first channel, which is formed on the main surface, a second channel, which intersects the first channel, the second channel is formed on the main surface, and the first channel is formed to extend from one end surface of the thermal transmission member to another end surface. As a result, although an increased cooling capacity can be created, but again only with a comparatively high design effort and additional chemical space requirements.

The present invention is therefore concerned with the problem of specifying at least one alternative embodiment for a heat exchanger of the generic type, which in particular overcomes the disadvantages known from the prior art.

According to the invention, this problem is solved by the subject matter of independent claim 1 . Advantageous embodiments are the subject of the dependent claims.

The present invention is based on the general idea of significantly increasing the cooling capacity of a heat exchanger and at the same time optimized and inexpensive to form by providing both a distributor for sprinkling water and corresponding channels introduced on an outer surface of a tube of the heat exchanger. The heat exchanger according to the invention for a fuel cell system has an upper header tank and a lower header tank as well as tubes arranged between them, in particular flat tubes, which are tightly accommodated at their upper end in associated openings, in particular passages, of a first tube base. At least one channel for water distribution or wetting of the outer lateral surface with sprinkling water is provided on an outer lateral surface of at least one of these tubes, with a distributor being provided in the area of the first tube plate, in particular below it, which is fluidically connected to the at least one channel of the at least one egg pipe is connected, whereby sprinkling water is routed from the distributor to the individual channels on the outer shell surfaces of the pipes and these can thus be subjected to sprinkling water during operation of the heat exchanger, whereby an evaporation effect and thus an improved cooling capacity is achieved with an otherwise identically sized cooler and equally large cooling air flow can be. The enthalpy of vaporization required to vaporize the sprinkling water is taken as thermal energy from the immediate surroundings, which cools down as a result. The increase in performance obtained by the heat exchanger according to the invention takes place without increasing an end face or, in general, a heat transfer area or an air mass flow, as a result of which neither the space requirement nor the fan output are significantly increased. With the at least one channel on the at least one outer lateral surface of the at least one pipe, a preferably uniform distribution of the sprinkling water over the outer lateral surface of the pipe can be achieved, whereby a large-area evaporation of the sprinkling water and thus also a significant increase in performance of the heat exchanger can be achieved. The tubes are expediently designed as flat tubes, with the at least one channel being designed as a groove or as a bead. Such a groove or bead can be a folded groove, for example, if the flat tube is designed as a folded flat tube, for example. This makes it possible to use the fold that is already present on the folded tube as a channel for distributing the trickling water on the outer lateral surface of the flat tube, which means that in this case, in purely theoretical terms, folded flat tubes known from the prior art can be used to implement the heat exchanger according to the invention can.

Furthermore, the tubes can also be designed as welded tubes. This makes it possible to use the bead present on the welded tube as a channel for distributing the sprinkler water on the outer lateral surface of the flat tube, which means that in this case, purely theoretically, welded flat tubes known from the prior art can be used to implement the heat exchanger according to the invention .

In addition or as an alternative to the fold or bead, additional channels can also be formed, via which the sprinkler water can be distributed. This applies regardless of how the tube is manufactured and is also possible with tubes that otherwise have no fold or bead, for example extruded tubes.

It is of course clear that for a better distribution of the sprinkling water not only the channel formed by a fold can be used, but also other additionally embossed channels that branch out with the channel formed by the fold and thus a large-scale distribution of the sprinkling water over the outer jacket surface of the flat tube and thus also enable a large-area evaporation of the sprinkler water and thus an increased cooling capacity. In an advantageous development of the solution according to the invention, the duct is arranged exclusively on a broad side of at least one flat tube, with a duct base touching an opposite broad side. With such a channel geometry, a significant increase in the surface area of the flat tube available for heat transfer can be achieved, with the channel offering a large surface area in contact with the sprinkler water flowing in the channel due to its comparatively great depth, as a result of which a high cooling capacity can be achieved . Sufficient evaporation water can be transported into the cooling network through a deepened channel, which means that more water can be provided over the entire channel length if possible.

At the same time, with a channel designed in this way, not only can a broad side of the flat tube be cooled superficially in the area of the channel, but also a particularly effective cooling of the flat tube, namely both on a broad side and on the comparatively deep channel walls. By touching the channel base with the opposite broad side, the flat tube can also be divided into different longitudinal channels, for example soldering the channel base to an inside of the opposite broad side also causes the flat tube to be stiffened.

By soldering the bottom of the channel to the opposite broadside, local cooling of the opposite broadside is even possible due to the sprinkler water present in the channel.

In a further advantageous embodiment of the solution according to the invention, at least one channel is arranged on each of the two broad sides of at least one flat tube and touches with its respective channel base. This makes it possible to subdivide the flat tube into different longitudinal channels in the flat tube, separated from one another by two opposite channels in each case, where, due to the two channels dividing the flat tube, a comparatively large surface for evaporation of sprinkling water can be created on both broadsides. This solution also leads to a symmetrical tube, thus preventing the tubes from having to be straightened / sorted or oriented in the manufacturing process of the cooler core.

This advantage can also be found in a further advantageous development of the solution according to the invention, in which at least one channel is arranged offset on each of the broad sides of at least one flat tube, with a channel bottom touching an opposite broad side (Fig. 10, variant c).

In an advantageous development of the heat exchanger according to the invention, the at least one channel has a triangular, a trapezoidal or a segment-shaped cross section. It is of course conceivable that both the broad side or the surface on the broad side and the channel walls themselves still have structuring, for example knobs or beads, which form a further increase in the surface area available for evaporation, resulting in a further improved Evaporation and thus further improved cooling can be achieved.

The distributor is expediently designed as a second tube sheet which, together with the first tube sheet, forms a collection space for sprinkling water. Such a variant with a "double tube plate" enables an extremely small installation space and material requirement, since the first tube plate can already be used for part of the distributor. Simultaneous production of the distributor with the production of the heat exchanger, for example in a joint soldering process, is also conceivable, as a result of which the heat exchanger according to the invention can be produced with only marginally higher production costs.

Alternatively, the distributor can also be designed separately from the first tube sheet and can be arranged below and/or in front of the tubes in the direction of flow. This makes it possible to retrofit the distributor even in known heat exchangers and thereby significantly increase their cooling capacity. In particular, a space-optimized solution can be created by a distributor arranged in the direction of flow in front of the tubes or in front of the first tube sheet, which enables a significant increase in performance potential in terms of cooling capacity with a slightly larger space requirement.

In a further advantageous embodiment of the solution according to the invention, the distributor is designed in the manner of a rake and engages with rake tines between individual tubes of the heat exchanger, with outlet openings for sprinkler water being arranged on the rake tines. A distributor formed in this way is also particularly advantageous for a retrofit solution, since it can be retrofitted to one independently of the actual heat exchanger, provided that at least a distance between two calculation prongs of the distributor correlates with a distance between two tubes of the heat exchanger.

The present invention is also based on the general idea of a fuel cell system with at least one fuel cell and a heat exchanger that controls it, in accordance with the previous paragraphs. The sprinkling water used to increase the performance of the heat exchanger is a combustion product of the fuel cell. This makes it possible, at least to a large extent, to dispense with separately entrained sprinkling water, since the sprinkling water required to increase the performance of the heat exchanger is generated by the fuel cell itself during its operation. In addition or as an alternative, at least a small tank for carrying along and storing sprinkling water can of course also be provided, with the use of the water produced as a combustion product of the fuel cell as sprinkling water offering a considerable advantage. The present invention is also based on the general idea of equipping a motor vehicle with such a fuel cell system and thereby obtaining a motor vehicle that is space-optimized, powerful and has a significantly increased range.

All in all, with the heat exchanger according to the invention, with the fuel cell system according to the invention and with the motor vehicle according to the invention, a significant increase in cooling capacity can be achieved without any significant influence on an air-side pressure drop, without a significantly larger installation space requirement and without a significant enlargement of the heat exchanger or increase a fan power.

Further important features and advantages of the invention result from the subclaims below, from the drawing and from the associated description of the figures based on the drawings.

It goes without saying that the features mentioned above and those still to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

Preferred exemplary embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, with the same reference numbers referring to the same or similar or functionally identical components.

They show, each schematically: 1 shows a sectional view through a heat exchanger according to the invention in the area of a first tube sheet with a second tube sheet to form a distributor,

FIG. 2 shows a representation as in FIG. 1 , but with a different second one

tube sheet,

3 shows a further possible embodiment of a device according to the invention

distributor with an inclined distributor,

Fig. 4 shows a representation as in Fig. 3, but with a recessed center

distributor,

5 shows a representation with a distributor arranged on both sides,

6 shows a representation with a rake-like distributor arranged on one side and upstream of the heat exchanger,

Fig. 7 to 10 different cross-sectional shapes through a tube of a heat exchanger according to the inventions to the invention.

Corresponding Fig.1 to 6, a heat exchanger 1 according to the invention for a fuel cell system 2 of a motor vehicle 3 has an upper header tank 4 and a lower header tank (not shown), between which ste existing tubes 5 are arranged, which at their upper end tightly in associated openings 6, for example drafts, a first tube sheet 7 are included men. The tubes 5 can be designed as flat tubes, for example, and have at least one channel 9 (cf. in particular also FIGS. 7 to 10) for water distribution, in particular for the distribution of sprinkler water 11, on an outer lateral surface 8. Below the first tube sheet 7 is a distributor 10 is provided, which is fluidically connected to the at least one channel 9 of the at least one pipe 5 and collected in the sprinkler water 11, for example as a combustion product of a fuel cell of the fuel cell system 2, and to increase the cooling capacity during operation of the heat exchanger 1 via the at least one outer lateral surface 8 is delivered to at least one tube 5 . This allows the sprinkling water 11 (see FIG. 4) to evaporate on the at least one outer surface 8, with the energy required for this being extracted from the heat of a coolant flowing in the tubes 5 and the coolant in the tubes 5 being cooled better as a result.

With the heat exchanger 1 according to the invention, a design that is optimized in terms of installation space and at the same time an increased cooling capacity can be achieved without having to increase the fan output, for example, which would lead to a larger or more powerful motor vehicle 3 in particular in the case of a motor vehicle 3 powered by a fuel cell Fan would have to be installed, which requires more electrical energy and thereby the range of the motor vehicle 3 is limited. At the same time, in the heat exchanger 1 according to the invention and its use in a motor vehicle 3 equipped with a fuel cell system 2, the water produced as combustion product in the fuel cell can be used as sprinkler water 11 for improved cooling. A separate water transport is dispensable Lich, whereby the motor vehicle 3 can be made lighter.

The tubes 5 can be in the form of flat tubes, with at least one channel 9 being in the form of a groove or a bead. The at least one channel 9 can also be arranged in the area of a fold 12 (cf. FIG. 1) or a weld seam if the pipe 5 is designed, for example, as a folded pipe or as a welded pipe. This makes it possible to use the IN ANY way through the fold 12 which cross section as a channel 9 . The amount of sprinkling water 11 distributed via the distributor 10 over the at least one outer lateral surface 8 of the at least one pipe 9 allows both a uniform wetting of the outer lateral surface 8 due to the channels 9, which are preferably designed as beads or channels, and thus at the same time a uniform cooling of the same the sprinkling water 11 evaporating during operation of the heat exchanger 1. Of course, a cross-sectional geometry of the at least one duct 9 can result from the production process, in particular with regard to a manufacturing process for the respective pipe 5, so that the at least one duct 9 can, for example, be formed by a folding process, a welding process or an extrusion process.

The channels 9 attached to the outer jacket side 8 of the tubes 5 form connections or passages below half of the ribs 13 (see FIGS. 1 and 7), which allow water to be transported from rib arch to rib arch along a longitudinal direction 14 of the tubes 5.

Of course, not only a corresponding channel 9 can be provided for an improved distribution of the sprinkling water 11 on the outer lateral surface 8 of at least one pipe 5, but also ribs 13 or other depressions or elevations, which on the one hand provide a surface available for heat transfer increase and allow for a steering of the running on the tubes 5 sprinkling water 11, whereby improved evaporation and thereby improved cooling can be achieved. In particular, the sprinkling water 11 should be distributed as evenly as possible over the length of the pipe and over all the pipes 5 . If one looks again at the heat exchanger 1 according to the invention as shown in FIG. 1, the distributor 10 is designed as a second tube plate 17, which offers the great advantage that, in principle, no complex changes to a previous construction are required. Only an adjustment of the outer shell surfaces 8 of the tubes 5 is required for this. A type of double tube plate in the manner of a second tube plate 17 is also shown in the embodiment of the heat exchanger 1 according to the invention according to Fig. 2, in which case the second tube plate 17 is designed as a thin-walled sheet metal part, which on the one hand creates a material connection with the Tubes 5 and the first tube plate 7, but nevertheless, compared to the heat exchanger 1 according to FIG 1 according to Fig.

1 enlarged.

In the distributor 10 according to FIG. 3, this has a sloping bottom 19, whereby the respectively associated pipe 5 can be subjected to varying degrees of sprinkler water 11 in the direction of flow 20. The ge according to FIG. 3 shown tube 5 has at least two extending over the longitudinal direction by 14 channels 9, wherein the front in the direction of travel and rear in flow direction 20 through channel 9 more sprinkler water 11 leads.

The heat exchanger 1 according to FIG. 4 has a distributor 10 with an angled bottom 19 which is fluidly connected at its lowest point to the channel 9 and via this sprinkling water 11 derives on the outer lateral surface 8 of the tube 5 designed as a flat tube.

According to FIG. 5, a two-part distributor 10 is shown, which is arranged in front of and behind the tubes 5 in the direction of travel. The aim of the distributor variants is that the water from the distributor 10 as completely as possible in the channels 9 and from it is then distributed over the heat exchanger 1, in particular a uniform distribution should also be achieved as independently as possible of the driving speed.

The idea behind the two-part variant is that the two parts of the distributor 10 with ribs 24 on the pipe 5 that extend in the direction of flow 20 form a space 23 for water distribution and the sprinkler water 11 from this space 23 into the channels 9 and from there into Tube longitudinal direction 14 flows over the tubes 5. The ribs 24 run transversely to the channel 9 and can extend over the entire broad side 15 of the tubes 5. A rib curve is a rounding of a wave-shaped rib 24, that is to say the part of the rib 24 which is soldered to the tube 5. If the outer surface of the tube 5 is flat and the rib bends are also flat or have no interruptions, a continuous soldering is achieved over the entire depth of the cooler. A Wasserver distribution along the tubes 5, that is, in the longitudinal direction would not be possible. With the channel 9 “below” the rib curves, an opening can be achieved between the distributor 10 and the broad side 15 of the pipe 5, whereby the sprinkler water 11 can be distributed undisturbed from the respective ribs 24 or rib curves in the longitudinal direction of the pipe and ideally at each rib 24 a small part of the sprinkling water 11 emerges from the channel 9 and is distributed over the pipes 5 or their broad sides 15a, 15b and thus contributes to increasing the heat transfer.

In a further embodiment, the distributor can also be mounted on one side in front of or behind the tubes 5 . In addition, a cover can be provided on the opposite side in order to prevent the sprinkling water 11 from escaping.

In addition to the channels 9 fitted in the tube 5, a reshaping can be carried out on the rib 24 (in the costal arch or radius), which is for one Passage/opening ensures through which sprinkling water 11 can be passed from rib cage to rib cage and thus also distribution of the irrigation water 11 along the longitudinal direction 14 of the tubes 5 is made possible. This recess can be made either as a cutout (by punching/cutting) or simply by embossing back the corresponding part of the rib arch. The embossing can take place during the rolling process of the rib 24 or afterwards, before the rib 24 is installed in the tube 5/rib package (radiator network). In order to maintain the performance of the rib 24 or to prevent a deformation of the gills in the rib 24 in the area of this reshaping, the gill field in the vicinity of this reshaping must or can be adjusted/optimized for this reshaping if necessary. The shape of the recess/embossing can be V-shaped, trapezoidal, or (circular) arc-shaped. The water distribution can be improved by embossed ribs 24 in particular, in particular the channels 9 arranged on the broad sides 15a, 15b can be expanded - or the smaller channels already present on welding pipes, for example, can be expanded to such an extent that they can be Combination with such a rib 24 have sufficiently large cross sections to allow water distribution

6 in turn shows a distributor 10 which is designed in the manner of a rake and engages with rake tines 21 in spaces between two adjacent flat tubes, outlet openings 22, for example also nozzles, for sprinkling water 11 being arranged on the rake tines 21 are. Depending on the driving speed of the motor vehicle 3 equipped with the heat exchanger 1 according to the invention, the sprinkling water 11 is distributed more or less over a large area over the outer lateral surface 8.

The two-piece variant with a two-sided or one-sided distributor, or the rake are embodiments that can be retrofitted or without one fundamental change in the manufacturing process as an add-on at the end of the previous production line. The embodiment with the rake is similar to that sketched with the two-part distributor 10, only that here the space for the water distribution is not exactly defined.

The distributor 10 can in principle be designed separately from the heat exchanger 1, as shown for example in FIG. 6, or form part of the heat exchanger, as shown in FIGS the distributor 10 is at least partially cohesively connected to the heat exchanger 1, for example with its first tubular surface 7, in particular soldered.

If one considers the individual possible cross-sectional shapes of the tubes 5 (cf. FIGS. 7 to 10), which are by no means exhaustive, one can see a cross section of a tube 5 according to FIG is arranged, in which case a channel base 16 does not touch the opposite broadside 15b. However, ribs 13 or beads can be provided on both broad sides 15a, 15b. If you look at the cross section of the tube 5 according to FIG. 8, you can see two channels 9 there, which are also arranged exclusively on the broad side 15a, the channel base 16 of which, however, touches the opposite broad side 15b and, for example, is even bonded to it , whereby the tube 5 designed as a flat tube is divided into several chambers in the longitudinal direction 14, that is, according to FIGS. 7 to 10 orthogonally to the plane of the sheet.

If one considers the cross-sectional shape of the tube 5 according to FIG. 9 as a further exemplary embodiment, one can see that channels 9 are provided on both broadsides 15a and 15b, which are in the channel base 16 with the opposite channel base 16 or also the broadside touch 15a, 15b or not able to touch. In the example, they do not touch with their respective channel base 16 on the left channel 9, but on the right channel 9.

A cross-sectional shape of the ducts 9 according to FIGS. 7 to 8 is rounded, although, of course, ducts 9 with a rectangular cross section (cf. FIGS. 10b and 10c) or trapezoidal ducts 9 (cf. FIG. 10a) or those not shown can also be used triangular, semicircular, oval segment-shaped channels 9 can be provided. The width of the respective channel 9 or the depth of the channel bottom 16 allows the irrigation water 11 to be routed along the longitudinal direction 14 of the respective pipe 5 as well as to distribute it and thus evaporate it and thus indirectly in turn improve the cooling capacity of the heat exchanger 1 influence.

With the heat exchanger 1 according to the invention for a fuel cell system 2, a significantly increased cooling capacity is possible, please include the same size heat exchanger, with the water occurring as a combustion product being able to be used as sprinkling water 11 at the same time, particularly in a fuel cell system 2. As a result, significantly improved cooling and thus temperature control of the motor vehicle 3 equipped with such a fuel cell system 2 can be achieved.

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Claims

patent claims

1. Heat exchanger (1) for a fuel cell system (2) with an upper Sam melkasten (4) and a lower header tank, between which upright tubes (5) are arranged, which at its upper end closely in associated Openin gene (6) of a first tube sheet (7) are accommodated, characterized in that

- that at least one channel (9) for the distribution of sprinkling water (11) is provided on an outer lateral surface (8) of at least one pipe (5),

- that below the first tube plate (7) a distributor (10) is provided which is fluidically connected to the at least one channel (9) of the at least one tube (5).

2. Heat exchanger according to claim 1, characterized in that the tubes (5) are designed as flat tubes, wherein the at least one channel (9) is designed as a channel or bead.

3. Heat exchanger according to claim 2, characterized in that the channel (9) is arranged exclusively on a broad side (15a) of at least one flat tube, with a channel base (16) touching an opposite broad side (15b).

4. The heat exchanger as claimed in claim 2, characterized in that at least one channel (9) is arranged on both broad sides (15a, 15b) of at least one tube (5) and touches each other with their respective channel base (16).

5. Heat exchanger according to one of the preceding claims, characterized in that at least one channel (9) has a triangular, an oval segment-shaped, a trapezoidal or a circular segment-shaped cross-section.

6. Heat exchanger according to one of the preceding claims, characterized in that the distributor (10) is designed as a second tube plate (17) which forms a collecting space for sprinkling water (11) with the first tube plate (7).

7. Heat exchanger according to one of claims 1 to 5, characterized in that the distributor (10) is formed separately from the first tube plate (7) and is arranged under half of the same.

8. Heat exchanger according to one of claims 1 to 5, characterized in that the distributor (10) is formed separately from the first tube sheet (7) and is arranged in the flow direction (20) in front of or behind the tubes (5).

9. Heat exchanger according to claim 8, characterized in that the distributor (10) is designed in the manner of a rake and with rake tines (21) engages between the individual tubes (5), outlet openings (22) being provided on the rake tines (21). for sprinkling water (11) are arranged.

10. Heat exchanger according to one of the preceding claims, characterized in that that the distributor (10) is at least partially bonded to the heat exchanger (1).

11 . Fuel cell system (2) with at least one fuel cell and a temperature-controlling heat exchanger (1) according to one of the preceding claims, wherein the sprinkling water (11) is a combustion product of the fuel cell.

12. Motor vehicle (3) with a fuel cell system (2) according to claim 11.

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