Flow device for supplying a medium flow to an intake of a fuel

Abstract

The invention relates to a flow device (30) for supplying a flow of medium (1) to an inlet opening (42) of a fuel cell stack (40), the flow device (30) having a flow distributor (10) which has a main flow section (12) and a plurality of branch flow sections (14) which branch off from the main flow section (12) and which are connected in terms of flow to the inlet opening (42) of the fuel cell stack (40), the flow device (30) has a main flow section (12), and wherein an inlet opening (11) for supplying the medium flow (1) into the main flow section (12) is formed on the main flow section (12), and wherein the flow device (30) further has a flow insert (20) which is arranged in the main flow section (12) and is fluidically connected to the inlet opening (11) and which has at least one flow opening (22, 24), and the main flow section (12) and the branch flow section (14) are used for supplying the medium flow (1) to the flow inlet (42) in a uniformly distributed manner through the main flow section (12) and the branch flow section (14).

Description

Technical Field

[0001] The present invention relates to a flow device for supplying a medium flow to an inlet of a fuel cell stack, wherein the flow device has a flow distributor having a main flow section and a plurality of branch flow sections branching from the main flow section for connection to the inlet of the fuel cell stack in terms of flow technology, and wherein an inlet hole is formed at the main flow section for supplying the medium flow into the main flow section. The present invention also relates to a fuel cell system having a plurality of fuel cell stacks and such a flow device. Background Art

[0002] The flow distributor for supplying a medium flow to a flow inlet of a fuel cell stack as mentioned in the introduction is known from the prior art and is described, for example, in Figure 1 is schematically shown in a cross-sectional view.

[0003] Figure 1 The flow distributor 10 shown has a main flow section 12 and a branch flow section 14 branching therefrom, which can be connected to the inlet of the fuel cell stack ( Figure 1 (not shown). Figure 1 As shown, in the illustrated orientation, an inlet opening 11 is provided on the bottom side 17 of the flow distributor 10 , through which the medium flow 1 flows into the flow distributor 10 in order to be distributed to the fuel cell stack.

[0004] Since the medium flow 1 passes through the branch flow sections 14 in sequence from the main flow section 12 , the same medium quality, temperature and velocity of the medium flow 1 cannot be provided at all branch flow sections 14 due to hydraulic and heat losses, which is exactly what is required for all fuel cell stacks to operate in a balanced manner.

[0005] Figure 2 A solution to this problem in the prior art is shown. Figure 1 In contrast, the main flow section 12 does not have a constant cross section here, but has a cross section that tapers gradually along its main extension direction. For this purpose, a longer second side wall 18 of the main flow section 12 is placed obliquely.

[0006] Even though a higher degree of uniform distribution of the medium flow to the branch flow section 14 in terms of mass and velocity can thereby be achieved, a higher degree of uniform distribution can still be desired.

[0007] In particular, with regard to the medium temperature of the medium flow 1, Figure 1It can be found in the flow distributor 10 that the medium temperature decreases significantly as the distance of the branch section 14 from the inlet hole 11 increases, that is, the decrease can reach several degrees Celsius, which may have a relevant impact on the chemical reaction. This means that the fuel cell stack cannot achieve a consistent supply in terms of the flow parameters of the medium flow 1, and thus is subjected to gradually different loads during its service life, thereby causing more serious power loss and aging than expected, and sometimes even unable to continue to operate. Summary of the invention

[0008] The object of the present invention is to at least partially eliminate the aforementioned disadvantages. In particular, the object of the present invention is to provide a medium flow distribution that is as uniform as possible for the individual fuel cell stacks in a cost-effective and simple manner.

[0009] The above object is achieved by a flow device having the features of claim 1 and a fuel cell system having the features of claim 19. Further features and details of the invention are derived from the dependent claims, the description and the figures. Here, the features and details described with respect to the flow device according to the invention are obviously also used in connection with the fuel cell system according to the invention, and vice versa, so that the disclosures of the various inventive aspects are always or can be referred to one another.

[0010] According to the present invention, a flow device for supplying a medium flow at an inlet of a fuel cell stack is provided, wherein the flow device has a flow distributor having a main flow section and a plurality of branch flow sections branching from the main flow section for being connected to the inlet of the fuel cell stack in terms of flow technology, and wherein an inlet hole is formed at the main flow section for supplying the medium flow into the main flow section, in particular into a flow insert arranged therein. The flow device also has a flow insert arranged in the main flow section and connected to the inlet hole in terms of flow technology, the flow insert having at least one flow hole for supplying the medium flow to the inlet of the fuel cell stack via the main flow section and the branch flow section in a uniformly distributed manner.

[0011] According to the present invention, the task is accomplished by using a flow insert specially arranged in the main flow section of the flow device. The flow insert is therefore designed to supply the medium flow to the branch flow section in a uniformly distributed manner through at least one flow hole thereof and to the inlet of the fuel cell stack through it. The uniform distribution of the medium flow is provided here by the at least one flow hole, because unlike the prior art, the medium flow no longer flows into the main flow section only at a single position, that is, at the inlet hole, but can flow out through at least another flow hole in the main flow section that can be arbitrarily positioned along the flow insert. By guiding the medium flow in the flow insert, the medium flow is prevented from flowing out unevenly from the inside of the main flow section to the branch flow section. By using the flow device of the present invention, the medium flow flowing into the flow distributor through an inlet (or optionally multiple inlets, as described below) can be more evenly distributed to the branch flow section and the inlet of the fuel cell stack, especially in terms of the mass, temperature and / or velocity of the medium flow. The "uniform distribution" described here does not necessarily mean a perfect uniform distribution in a mathematical sense, because this is actually impossible to achieve. Rather, it means achieving the greatest possible or optimal uniform distribution of the flow parameters of the medium flow.

[0012] The fuel cell stacks can be integrated into a fuel cell system. The fuel cell system can include other peripheral devices and devices for operating the fuel cell stacks, such as valves, pumps, circulation fans, etc.

[0013] Furthermore, the flow insert and the flow distributor can be independent components (especially one-piece components) or can be one-piece flow devices. The first variant thus has the advantage that an existing flow distributor can be easily retrofitted by simply providing it with a flow insert that can be fixed in the main flow section. The second variant has the advantage that it is easy to manufacture, for example using 3D printing. The flow distributor itself and its main flow section and tributary flow section can also be manufactured in one piece or in multiple pieces.

[0014] It may be preferred that at least one of the at least one flow hole is an intermediate flow hole, which is formed between the first end and the second end of the flow insert. These two ends may in particular be the longitudinal ends of the flow insert. They may coincide with or be adjacent to the ends or side walls (such as the top side and the bottom side) of the main flow section, respectively. By arranging one or more flow holes in the form of intermediate flow holes between these two ends, a uniform distribution of the medium flow at the fuel cell stack is allowed, and the fuel cell stack is arranged between these two ends with its inlet at the flow height or in the flow direction or the main extension direction of the flow insert. This is particularly advantageous when using more than two fuel cell stacks. For example, there may be three, four, five, six or more fuel cell stacks. The number of branch sections corresponds in particular to the number of fuel cell stacks here, so that each fuel cell stack and its inlet correspond to a branch section and are connected by flow technology.

[0015] It may be preferred that the flow insert has a plurality of intermediate flow holes which are spaced apart from one another in the main extension direction of the flow insert. By providing a plurality of intermediate flow holes, for example two, three, four or more intermediate flow holes, in particular a more uniform temperature distribution of the medium flow to the inlet of the fuel cell stack can be further improved. By spacing apart from one another, in particular uniform spacing, mutual influences between the individual medium subflows which can be divided in the flow insert by the intermediate flow holes and flow out of the intermediate flow holes can be substantially avoided or minimized, so that these medium subflows can be conveyed to the branch sections without interference.

[0016] It may also be preferred that each intermediate flow opening is located at the flow height of the respective branch flow section. The flow height here refers to the height measured along the flow direction of the medium flow in the flow insert (i.e. along the main extension direction of the flow insert) and thus along and around the branch flow sections. In other words, each intermediate flow opening is associated with a branch flow section, so that the individual medium subflows of the medium flow can flow directly through the intermediate flow opening into the branch flow section.

[0017] It may also be preferred that at least one of the at least one intermediate flow hole is formed on the flow insert side of the flow insert facing away from the branch section, especially the branch section opening facing away from the branch section. This can achieve a flow that surrounds the flow insert on the back side of the branch section, especially radially and flows to the branch section. Here, the medium flow guided in the flow insert can be left out through an intermediate flow hole as a medium shunt toward the side wall (here referred to as the second) of the main flow section, collide with it and be deflected, so as to flow around the flow insert in the opposite direction, especially at the same flow height, to the branch section. Therefore, it is possible to provide a medium shunt separated from the medium flow in an advantageous manner, especially for multiple branch sections and fuel cell stacks, wherein the uniform distribution of these medium shunts in terms of flow parameters (especially mass, temperature and velocity) is quite high. The flow impulse of the medium flow is advantageously reduced here and the flow of the medium flow is well aligned with the branch section. Therefore, it is also possible to obtain as similar an incoming flow surface as possible for all branch sections and the interaction between the local similar parts of the shell, so that each branch section is subjected to the same heat loss.

[0018] Additionally or alternatively, it may also be preferred that a flow guide is provided on at least one of the at least one intermediate flow holes for guiding the medium flow from the at least one intermediate flow hole through the main flow section into one of the branch flow sections. The flow guide may be straight, inclined (relative to the vertical direction or the main extension direction of the flow insert) and / or curved (in particular away from the branch flow section). In addition, the flow guide may be arranged on the back side of the aforementioned flow insert, or on the side of the flow insert facing the branch flow section. Positioning therebetween is obviously also achievable. The flow guide allows controllable flow guidance to prevent undesirable swirl or mixing of the medium diversion from the flow hole.

[0019] It may be preferred that at least one of the flow guides is designed to generate a flow vortex of the medium flow that surrounds at least a portion of the flow insert and enters one of the branch flow sections. The length and swirl of the flow vortex can be adjusted by the position of the flow guide and its shape (as described above, such as tilting and / or bending). The momentum of the medium flow or medium shunt passing through the flow insert is deflected here. As a result, a desired controllable flow vortex surrounding the flow insert is provided between the (second) side wall of the main flow section and the flow insert to further improve the uniform distribution of the medium flow for the fuel cell stack. Unlike the above-mentioned variant in which the medium shunt flows out through an intermediate flow hole on the back side of the flow insert, the medium shunt is not shunted at the (second) side wall of the main flow section in this case. This enables a uniform distribution of the medium flow while the medium flow is well aligned with the branch flow section.

[0020] It may also be preferred that the at least one flow guide extends between the flow insert and the second side wall of the main flow section of the flow distributor. In particular, the flow guide can be flow-tight with respect to one side, so that the flow can be diverted to one side or only allowed to flow to one side. The flow guide can, for example, be an integral component of the flow insert and / or the flow distributor, or be fixed to one or both of them. The second side wall of the main flow section is in particular a wall or a side surrounding the flow insert. The first side wall and the third side wall of the main flow section can be arranged at the end sides of the main flow section, respectively, wherein they can form the top side and the bottom side of the main flow section.

[0021] Additionally or alternatively, it may be preferred that at least one of the at least one intermediate flow opening is formed on the flow insert side of the flow insert facing the branching section. Such an intermediate flow opening can be provided as an alternative or in addition to the intermediate flow opening on the side facing away from the flow insert. Thus, a direct flow to the branching section is possible (without flowing around the flow insert), but also a branched flow of the medium can be conveyed to the branching section from both sides of the flow insert.

[0022] It may also be preferred that the at least one intermediate flow opening is formed in the flow insert as a slot. The slot may, for example, have a rectangular or oval elongated shape. The slot may extend in the longitudinal direction greater than in the width direction. The slot may be formed transversely, in particular perpendicularly, to the main extension direction of the flow insert along its length. It can be easily formed in the flow insert and may have a limited flow cross section in order to avoid a complete outflow of the medium flow in the flow insert and to allow only a limited, controllable flow to flow out.

[0023] It can be provided that the second end of the flow insert away from the inlet hole is arranged on the first side wall of the flow distributor. However, it is possible and preferred that one of the at least one flow hole is a terminal flow hole, which is formed at the second end of the flow insert away from the inlet hole. Thus, the second end is not arranged on the first side wall of the flow distributor and is therefore not sealed, but is open through the terminal flow hole. The terminal flow hole can occupy the entire or nearly the entire cross-section of the flow insert, so that the second end is completely open. This is a relatively simple possible way to simply and evenly distribute the medium flow from the inlet hole to the fuel cell stack that is higher up in the flow height or, in other words, is at the rear in the flow direction of the medium flow, without losing temperature, mass and / or speed due to flowing to the preceding fuel cell stack. The medium flow flowing out of the terminal flow hole can rebound at the first side wall and thus flow to the upper or rear tributary section. As mentioned above, the first side wall can be the top side of the main flow section here, and it can especially be opposite to the bottom side of the main flow section, located at or near the inlet hole.

[0024] It may also be preferred that the flow distributor has at least one further flow inlet for feeding the medium flow into the main flow section bypassing the flow insert and / or that the flow inlet is designed such that the medium flow can be fed into the main flow section bypassing the flow insert. For the latter variant, the flow inlet can be dimensioned to be correspondingly large and / or positioned such that the medium flow can flow into the main flow section between the flow insert and its second side wall in addition to flowing into the flow insert. This is particularly advantageous in combination with the end flow openings, since the lower or preceding branch flow sections can also be well supplied, ensuring that the medium flow is evenly distributed to the fuel cell stack.

[0025] It may also be preferred that the inlet is formed on the inlet portion branching off from the main flow section. This is particularly advantageous when the structural space in the main extension direction of the main flow section is narrow. In this case, the inlet and the inlet portion may also be located on the first side wall, from which the main flow section may extend along its main extension direction according to its length and / or a specified medium flow direction.

[0026] It may be preferred that at least one other inlet branching off from the main flow section is designed to have an inlet opening spaced apart from other inlets on the main flow section. Therefore, another medium flow can be supplied at another position, especially at a higher flow height, thereby allowing better medium flow distribution.

[0027] It may also be preferred that at least two flow inserts are arranged side by side in the flow distributor. These flow inserts can each be supplied with a medium flow via the same inlet opening or several inlet openings. This makes it easy to achieve a larger medium flow. It is advantageous here if the main flow section, and optionally also the branch flow section, is designed to have a larger width.

[0028] It may also be preferred that the flow insert and / or the main flow section is a tube. The design of the tube is relatively simple and especially cost-effective. Different cross sections of the tube are conceivable, such as round, square, oval, heart-shaped, or mixed forms of the above-mentioned shapes, etc.

[0029] In particular, the flow insert and the main flow section are spaced apart from each other, in particular omnidirectionally or radially. It may be particularly preferred that the flow distributor is arranged concentrically, in particular coaxially, with the main flow section. Thus, a substantially uniform spacing can be achieved between the main flow section and in particular its (second) side wall and the flow insert, through which the medium flow, in particular the generated medium branch flow, can flow to reach the branch flow section.

[0030] Finally, it may also be preferred that the branch section openings of the branch sections have different sizes. The branch section openings (also called the inlet of the branch section) are used for the inflow of the medium flow. The design of its different sizes can be achieved, for example, by corresponding throttling members at and / or in the branch section. The uniform distribution can also be further optimized by such different branch section opening sizes, in particular their diameters. If, for example, more medium flow enters the branch section that is located in front of the flow direction of the medium flow, it can be adjusted by reducing its branch section opening relative to the branch section that is located behind in the flow direction to obtain a more uniform distribution, because the medium flow entering from below must pass through a smaller opening cross-section, so the flow rate is limited. This can also be done intentionally to influence the uniform distribution of the mixing temperature at the inlet of the branch section.

[0031] The subject matter of the invention is also a fuel cell system having a plurality of fuel cell stacks and a flow device according to the invention, wherein a respective inlet of each of the fuel cell stacks is respectively connected flow-wise to a corresponding branch section of the flow device.

[0032] Therefore, the fuel cell system of the present invention brings the same advantages as described in detail with respect to the flow device of the present invention.

[0033] It may be preferred that the inlet of the fuel cell stack leads to the air side or the fuel side of the fuel cell stack. Accordingly, the medium flow may preferably be an air flow or a fuel flow, such as a hydrogen flow.

[0034] It is obviously also possible to use two or more flow devices according to the invention in a fuel cell system according to the invention. The flow devices can be used for different media and thus for different inlets of a fuel cell stack. For example, one flow device can be used for the air side of a fuel cell stack and another flow device for the fuel side of a fuel cell stack. However, multiple uses can also be advantageous in a media system of a device in which a central supply mechanism distributes the media to the individual subsystems, each of which has a series of fuel cell stacks. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Further advantages, features and details of the invention are derived from the following detailed description of an embodiment with reference to the drawing, which schematically shows:

[0036] Figure 1 A vertical cross-sectional view showing a flow distributor according to a first embodiment of the prior art,

[0037] Figure 2 A vertical cross-sectional view showing a flow distributor according to a second embodiment of the prior art,

[0038] Figure 3a A vertical cross-sectional view showing a flow device according to a first embodiment of the present invention,

[0039] Figure 3b Show Figure 3a A horizontal cross-sectional view of a flow device,

[0040] Figure 4a A vertical cross-sectional view showing a flow device according to a second embodiment of the present invention,

[0041] Figure 4b Show Figure 4a A horizontal cross-sectional view of a flow device,

[0042] Figure 5a A vertical cross-sectional view showing a flow device according to a third embodiment of the present invention,

[0043] Figure 5b Show Figure 5a A horizontal cross-sectional view of a flow device,

[0044] Figure 6a A vertical cross-sectional view showing a fuel cell system having a flow device according to a fourth embodiment of the present invention,

[0045] Figure 6b Show Figure 6a A horizontal cross-sectional view of a flow device,

[0046] Figure 7 A horizontal cross-sectional view showing a flow device according to a fifth embodiment of the present invention,

[0047] Figure 8 A horizontal cross-sectional view showing a flow device according to a sixth embodiment of the present invention,

[0048] Fig. 9 A horizontal cross-sectional view showing a flow device according to a seventh embodiment of the present invention, and

[0049] Fig.10 A vertical cross-sectional view of a flow device according to an eighth embodiment of the present invention is shown.

[0050] The same or functionally equivalent parts Figures 1 to 10 The same reference numerals are always used in the drawings. DETAILED DESCRIPTION

[0051] Obviously, the terms "horizontal" and "vertical" should not be understood as limiting, and are expressed only to clarify the spatial relationship between the diagrams.

[0052] Figure 3a An embodiment of a flow device 30 according to the invention is shown, which is improved compared to the flow distributor 10 known from the prior art by the flow insert 20 and further measures explained in detail below. The flow device 30 is shown here in a vertical cross section along the main extension direction (especially the longitudinal extension direction) of the flow insert 20, which also coincides with the flow direction of the supplied medium flow 1.

[0053] The flow insert 20 is arranged in the main flow section 12 of the flow distributor 10, which forms a main flow channel. The flow insert 20 is arranged at a distance from the second side wall 18 of the main flow section 12, which surrounds the flow insert 20 as a circumferential wall of the main flow section 12. In particular, the flow insert 20 is arranged concentrically in the main flow section 12.

[0054] The main flow section 12, the branch flow section 14 and / or the flow insert 20 may be designed in a tubular shape, such as Figure 3b As shown, the main flow section 12 and the flow insert 20 are Figure 3a The illustrated horizontal cross-sections of the main flow section 12 and the flow insert 20 are contrasted. Merely by way of example, the tubular cross-sections of the main flow section 12 and the flow insert 20 are shown here as circular, but one or both may also be rectangular, elliptical or heart-shaped, for example (see Figure 7 ).

[0055] like Figure 3aAs shown, the main flow section 12 comprises an inlet opening 11 on the respective bottom side 17 of the main flow section 12 (the bottom side 17 is in particular the third side wall of the flow distributor 10), which is connected to the flow insert 20 therein in terms of flow technology (or fluid technology). Thus, for example, it can contain a fuel cell stack 40 (see Figure 6a ) a medium flow 1 of air or fuel can be introduced into the flow insert 20 and flow therein along the main flow section 12 .

[0056] At the end of the flow insert 20, which is referred to here as the second end 23, a flow hole in the form of a terminal flow hole 24 is provided. For this purpose, the flow insert 20 is open at the second end 23. The second end 23 is opposite the first end 21, where the inlet opening 11 is located. Through the terminal flow hole 24, the medium flow 1 flows out of the flow insert 20 at the second end 23 and thus reaches the branch section 14 and its branch section opening 15 which are arranged behind or behind in the flow direction or the main extension direction of the main flow section 12 by bypassing the flow insert 20. In this case, the outflowing medium flow 1 (as shown by the corresponding arrows, which indicate the branching direction or medium branching of the medium flow 1) rebounds transversely, in particular perpendicularly, to the second side wall 18 and towards the inlet opening 11 at the first side wall 13 (in particular the top side) and is deflected to the subsequent branch section 14.

[0057] In addition to the inlet openings 11, two second inlet openings 11 are formed on the bottom side 17 of the main flow section 12 and next to the first end 21 of the flow insert 20, but a very large inlet opening 11 can also be provided, which is larger than the cross section of the flow insert 20 at the first end 21. Through these two inlet openings 11 or a very large inlet opening 11, the medium flow 1 is also introduced into the main flow section 12 without bypassing the flow insert 20. The medium flow 1 introduced in this way can directly reach the branch section 14 and its branch section opening 15 that are located in front or in front of the main extension direction of the main flow section 12 in the flow direction or the main extension direction of the main flow section 12.

[0058] Through the above combination, the medium flow 1 can be well evenly distributed in terms of mass, temperature and velocity in all branch sections 14 when the medium flow 1 does not pass through the flow insert 20 at the upstream branch section 14 and passes through the flow insert 20 at the downstream branch section 14. Here, the downstream branch section 14 is supplied with a large amount of insulating high-temperature medium through the flow insert 20 of corresponding size.

[0059] In addition, if Figure 3a As shown, the branch section openings 15 of the branch section 14 are designed to be different in size from each other, that is, the branch section openings 15 gradually become larger in the flow direction, for example. This will be achieved by setting a throttle of corresponding size at the branch section 14, such as Figure 3a shown, but for example in Figure 4a , 5a, 6a. However, this can also be achieved by different cross-sectional dimensions of the branch flow sections 14 in addition or alternatively. In this way, the medium flow 1 can also be distributed more evenly to the fuel cell stack 40.

[0060] Figure 4a Shown with Figure 3a In contrast to the alternative embodiment of the flow device 30, no end flow holes 24 are provided here. Instead, the flow insert 20 extends completely within the main flow section 12. In addition, intermediate flow holes 22 are provided here in the flow insert 20, which are formed here, for example, on the flow insert side 26 of the flow insert 20 facing away from the branch flow section 14. In addition, the intermediate flow holes 22 are designed here, for example, in the form of slits, the length of the slits being transverse to the main extension direction of the flow insert 20. These intermediate flow holes 22 are spaced apart from each other in the longitudinal extension direction of the flow insert 20 and are respectively arranged at the flow height of the flow height branch flow section 14. The size or number of the intermediate flow holes 22 is advantageously designed to be different from each other depending on the length of the distribution path.

[0061] like Figure 4b As shown in the horizontal cross-sectional view of the flow device 30 (at the flow height of one of the branch flow sections 24), the medium branch flow of the medium flow 1 is respectively guided to the second side wall 18 through the flow insert 20 at the flow height of the central flow hole 22, rebounds there, and then flows around the flow insert 20 toward the respective branch flow section 14, and thus reaches the respective fuel cell stack 40. Since it passes at the flow height of the branch flow section 14, it is possible to achieve a uniform distribution of the medium flow 1 to the flow of these fuel cell stacks 40 as a whole, and as mentioned above, it has a small inclination angle, because homogenization is achieved during the flow around the flow insert 20.

[0062] Figure 5a Another alternative embodiment of the flow device 30 is shown, which combines Figure 3a The implementation method and Figure 4a Modifications to the implementation methods of . Figure 5b Here, a horizontal cross section is shown above the end flow opening 24 of the flow insert 20. Figure 4a In contrast, the central flow opening 22 is formed here on the flow insert side 25 of the flow insert 20 facing the branch flow section 14, as shown in FIG. Figure 5b A combination of the intermediate flow holes 14 on the flow insert side 25 facing the branch section 14 and the intermediate flow holes on the flow insert side 26 facing away from the branch section 14 is also possible, such as Fig. 9 shown.

[0063] Figure 6aA fuel cell system 50 is shown with a plurality of fuel cell stacks 40, each of which in turn has an inlet 42 for a medium flow 1. The fuel cell stack 40 can be, for example, a polymer electrolyte membrane fuel cell stack or a solid oxide fuel cell stack. The inlet 42 is connected in terms of flow technology to a branch section 14 of a flow device 30 according to a further embodiment. Figure 6b Show Figure 6a A horizontal cross section of the flow device 30 at the flow height of one of the branch flow sections 14 .

[0064] Different from the previous embodiments, a flow guide 28 is provided on each of the intermediate flow holes 22 to guide the medium flow 1 from the respective intermediate flow hole 22 via the main flow section 12 to one of the branch flow sections 14 .

[0065] The flow guide element 28 here extends between the flow insert 20 and the main flow section 12 . Figure 6b The illustrated flow guide element 28 is arranged on the flow insert side 25 facing the branch flow section 14, thereby ensuring that the medium partial flow cannot flow directly from the central flow opening 22 to the respective branch flow section 14. Instead, the medium partial flow of the medium flow 1 must bypass the flow insert 20, so that a flow vortex around the flow insert 20 is generated by the respective flow guide element 28, which reaches the respective branch flow section 14 after flowing around (especially around) the flow insert 20.

[0066] also, Figure 6a An embodiment of a flow device 30 is shown, in which the medium flow 1 does not flow into the main flow section via the inlet opening 11 at the bottom side 17 of the main flow section 12, but rather enters via an inlet 16 which branches off laterally from the main flow section 12 and can be designed, for example, as a tube. Furthermore, a further optional inlet 16 is shown at approximately the middle flow height of the main flow section 12, via which the medium flow 1 can be additionally supplied.

[0067] in addition, Figure 6b An alternative embodiment is shown in which the flow insert 20 is almost completely surrounded by a clockwise flow and the medium flow 1 enters eccentrically, whereby the resulting inflow vortex is formed and further utilized in the entire main flow section 12, so that due to the longer flow path a particularly uniform flow into the corresponding branch section opening 15 is possible.

[0068] Figure 7 Show Figure 4b A modification of the embodiment of the flow device 30 is provided in which the flow insert 20 has a heart-shaped cross section instead of a circular cross section.

[0069] Figure 8An embodiment of a flow device 30 is shown in a horizontal cross-section, wherein the main flow section 12 has two flow inserts 20 extending next to one another, wherein the flow inserts 20 are arranged, for example, according to Figure 4a and 4b This embodiment can reduce the structural space of the main flow section 12 and greatly expand the flow toward the branch flow section 14, especially in the case of limited space, a wide and flat rectangular cross section can be provided for the branch flow section opening 14.

[0070] at last, Fig. 9 A further embodiment of a flow device 30 is shown in a horizontal cross-section, in which the flow insert 20 has a rectangular cross section. Here, a plurality of central flow holes 22 are provided not only on the flow insert side 25 facing the branch section 14, but also on the flow insert side 26 facing away from the branch section 14. In addition, two inlet openings 11 are provided in connection with the flow insert 20, and as indicated by the arrows in the figure, the medium flow division within the flow insert 20 can be seen.

[0071] at last, Fig.10 Another embodiment of the flow device 30 according to the present invention is shown, in which Figure 3a and 3b In contrast to the embodiment of the present invention, for example, only two branch flow sections 14 are provided, which are also arranged at the respective ends of the flow device 30, for example. Figure 3a and 3b The flow insert 20, Fig.10 The flow insert 20 in the embodiment is shortened, so there is a larger distance between the first side wall 13 and the flow insert 20 .

[0072] The above explanations of the embodiments describe the present invention only within the scope of examples.

[0073] Reference numerals list

[0074] 1 Medium flow

[0075] 10 Flow distributor

[0076] 11 Inlet hole

[0077] 12 Mainstream segment

[0078] 13 First side wall

[0079] 14 Tributary Section

[0080] 15 Branch opening

[0081] 16 Inlet

[0082] 17 Bottom

[0083] 18 Second side wall

[0084] 20 Flow Insert

[0085] 21 First End

[0086] 22 Intermediate flow hole

[0087] 23 Second End

[0088] 24 End flow holes

[0089] 25 Flow insert side toward (branch section)

[0090] 26 The side of the flow insert facing away from the (branch section)

[0091] 28 Flow guide

[0092] 30 Mobile Devices

[0093] 40 Fuel Cell Stack

[0094] 42 (fuel cell stack) inlet

[0095] 50 Fuel Cell System

Claims

1. A flow device (30) for supplying a medium flow (1) to an inlet (42) of a fuel cell stack (40), wherein: The flow device (30) comprises a flow distributor (10), the flow distributor comprising a main flow section (12) and a plurality of branch flow sections (14) branching off from the main flow section (12) for being connected to an inlet (42) of the fuel cell stack (40) in terms of flow technology, wherein an inlet hole (11) for supplying the medium flow (1) into the main flow section (12) is formed at the main flow section (12), The invention is characterized in that the flow device (30) further comprises a flow insert (20) arranged in the main flow section (12) and connected to the inlet hole (11) in terms of flow technology, and the flow insert has at least one flow hole (22, 24) for supplying the medium flow (1) to the inlet port (42) via the main flow section (12) and the branch flow section (14) in a uniformly distributed manner.

2. The flow device (30) according to claim 1, characterized in that: At least one of the at least one flow hole (22, 24) is an intermediate flow hole (22) formed between a first end (21) and a second end (23) of the flow insert (20).

3. The flow device (30) according to claim 2, characterized in that: The flow insert (20) has a plurality of intermediate flow holes (22) spaced apart from one another along a main extension direction of the flow insert (20).

4. The flow device (30) according to claim 3, characterized in that: Each intermediate flow hole (22) is located at the flow height of the corresponding branch flow section (14).

5. The flow device (30) according to any one of claims 2 to 4, characterized in that: At least one of the at least one intermediate flow opening (22) is formed on a flow insert side (26) of the flow insert (20) facing away from the branch flow section (14).

6. The flow device (30) according to any one of claims 2 to 5, characterized in that: At least one of the at least one intermediate flow hole (22) is provided with a flow guide (28) for guiding the medium flow (1) from the at least one intermediate flow hole (22) through the main flow section (12) into one of the branch flow sections (14).

7. The flow device (30) according to claim 6, characterized in that: The at least one flow guide element (28) is designed to cause the medium flow (1) to generate a flow vortex around at least a portion of the flow insert (20) and into one of the branch flow sections (14).

8. The flow device (30) according to claim 6 or 7, characterized in that: The at least one flow guide (28) extends between the flow insert (20) and a second side wall (18) of the main flow section (12) of the flow distributor (10).

9. The flow device (30) according to any one of claims 2 to 8, characterized in that: At least one of the at least one intermediate flow opening (22) is formed on a flow insert side (25) of the flow insert (20) that faces the branch flow section (14).

10. The flow device (30) according to any one of claims 2 to 9, characterized in that: The at least one intermediate flow hole (22) is formed as a slot in the flow insert (20).

11. The flow device (30) according to any one of the preceding claims, characterized in that One of the at least one flow hole (22, 24) is a terminal flow hole (24) formed at a second end (23) of the flow insert (20) remote from the inlet hole (11).

12. The flow device (30) according to any one of the preceding claims, characterized in that The flow distributor (10) has at least one further inlet opening (11) for supplying the medium flow (1) into the main flow section (12) bypassing the flow insert (20), and / or the inlet opening (11) is designed so that the medium flow (1) can be supplied into the main flow section (12) bypassing the flow insert (20).

13. The flow device (30) according to any one of the preceding claims, characterized in that The inlet hole (11) is formed on an inlet portion (16) branched from the main flow section (12).

14. The flow device (30) according to claim 13, characterized in that: At least another inlet portion (16) branched from the main flow section (12) is designed to have an inlet hole (11) spaced apart from other inlet portions (16) on the main flow section (12).

15. The flow device (30) according to any one of the preceding claims, characterized in that At least two flow inserts (20) are arranged side by side in the flow distributor (10).

16. The flow device (30) according to any one of the preceding claims, characterized in that The flow insert (20) and / or the main flow section (12) is a tube.

17. The flow device (30) according to any one of the preceding claims, characterized in that The flow insert (20) is arranged concentrically with respect to the main flow section (12).

18. The flow device (30) according to any one of the preceding claims, characterized in that The sizes of the branch section openings (15) of the branch sections (14) are different from each other.

19. A fuel cell system (50) having a plurality of fuel cell stacks (40) and a flow device (30) according to one of the preceding claims, wherein: The corresponding inlet opening (42) of each fuel cell stack (40) is connected in terms of flow technology to a corresponding branch flow section (14) of the flow distributor (10) of the flow device (30).

20. The fuel cell system (50) according to claim 19, characterized in that: The inlet (42) of the fuel cell stack (40) leads to the air side or the fuel side of the fuel cell stack (40).

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