Air humidifier

Abstract

The present invention relates to an air humidifier for transferring moisture from a moist exhaust airflow to a dry supply airflow. [Solution] In an air humidifier 1, which includes a humidifier block 4 that allows the exhaust airflow 3 and the supply airflow 2 to flow through with the medium separated, and which transmits moisture from the exhaust airflow 3 to the supply airflow 2, the separation of water from the exhaust airflow 3 is improved by providing a compensation device 18 within the housing 5 through which the exhaust airflow 3 can flow, for homogenizing the exhaust airflow 3.

Description

Technical Field

[0001] The present invention relates to an air humidifier for transferring moisture from a moist exhaust air flow to a dry supply air flow, particularly for a fuel cell system of a motor vehicle.

[0002] In order to optimize the fuel cell process, it is advantageous to humidify the supply air flow supplied to the cathode side of each fuel cell, that is, to increase the proportion of vaporous water. In any case, water is generated on the cathode side in the fuel cell process, so the exhaust air flow on the cathode side of each fuel cell contains a relatively large amount of moisture in the form of vapor and droplets. The moisture in the exhaust air flow can advantageously be used for humidifying the supply air flow. For this purpose, an air humidifier of the type described at the beginning is used. Depending on the operating state of the fuel cell system, the moist exhaust air flow may even contain liquid water, which can be disadvantageous for the air humidifier. Furthermore, the dehumidified exhaust air flow may also still contain liquid water, which can also be disadvantageous.

[0003] The present invention addresses the problem of providing an improved or at least alternative embodiment for an air humidifier of the type described above, which is particularly excellent by an improved separation of liquid water from the exhaust air flow. In this case, at the same time, an embodiment in which the pressure loss during the flow through the air humidifier is reduced is aimed at.

[0004] According to the present invention, this problem is solved by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

[0005] This invention is based on the general idea of ​​providing a compensating device within the housing of an air humidifier to homogenize the exhaust airflow. This compensating device is through which the exhaust airflow can pass, and is structured to homogenize the exhaust airflow, particularly in terms of flow direction and / or flow velocity, with respect to the cross-section through which the exhaust airflow passes as it passes through the device. In other words, the exhaust airflow is homogenized such that the flow direction and / or flow velocity of the exhaust airflow are homogenized with respect to the cross-section through which it can pass. As a result, downstream of the compensating device, the flow velocity and / or flow direction are almost the same across the cross-section through which it can pass, whereas upstream of the compensating device, there may be significant variation across the cross-section through which it can pass. Homogenization of the exhaust airflow reduces the pressure drop in the exhaust airflow, thereby improving the low-resistance flow of the air humidifier. At the same time, this facilitates water separation from the exhaust airflow. In particular, homogenization can reduce the average flow velocity of the exhaust airflow, thereby promoting water separation.

[0006] More specifically, according to the present invention, it is proposed that an air humidifier be provided with a humidifier block that allows the exhaust airflow and the supply airflow to flow through with the medium separated, and that transfers moisture from the exhaust airflow to the supply airflow. Furthermore, this air humidifier has a housing in which the humidifier block is arranged, and the housing has a vertical direction, a horizontal direction, and a height direction that extend perpendicularly to each other. The housing has an exhaust air inlet for supplying a humid exhaust airflow to the humidifier block, an exhaust air outlet for leading the dehumidified exhaust airflow out of the humidifier block, a supply air inlet for supplying a dry supply airflow to the humidifier block, and a supply air outlet for leading the humidified supply airflow out of the humidifier block. According to the present invention, a compensation device for homogenizing the exhaust airflow is arranged inside the housing through which the exhaust airflow can flow. This compensation device is arranged inside the housing so that the exhaust airflow can flow when the air humidifier is in operation.

[0007] Such a humidifier block can be formed, for example, by a membrane that is permeable to moisture or water and substantially impermeable to air. In this context, the concepts of "moist," "dry," "dehumidified," and "humidified" may be understood relatively, so that dehumidified exhaust air contains less moisture than moist exhaust air, and humidified supply air contains more moisture than dry supply air.

[0008] In an advantageous embodiment, the compensator may be located in a chamber through which exhaust airflow can pass, and may be structured to guide liquid water present in the compensator to a wall opening connecting this chamber to a water collection chamber. This allows the compensator to function as a water outlet, improving water separation. Furthermore, within the housing of the air humidifier, a separation wall may be located separating a water collection chamber from this chamber, which may have a water discharge opening for guiding the separated water. This chamber may be fluidly connected to the water collection chamber via a wall opening. Preferably, the wall opening extends from the side wall in the housing to the separation wall, preferably to a section of the separation wall adjacent to the wall opening.

[0009] Preferably, this chamber may be an exhaust air outlet chamber that leads the exhaust airflow out of the humidifier block and supplies it to the exhaust air outlet. In this case, the liquid water in the humidifier block is separated for the first time downstream of the humidifier block, and this liquid water can be used for moisture transfer to the supply airflow.

[0010] In an alternative embodiment, this chamber may be an exhaust air supply chamber that directs the exhaust airflow from the exhaust air inlet and supplies it to the humidifier block. In this location, a particularly large amount of liquid water can be separated from the exhaust airflow.

[0011] The compensating device has an inlet and an outlet surface, as it is passable by the exhaust airflow. Preferably, in this case, the compensating device may be positioned within the chamber such that the outlet surface supplies liquid water present on the outlet surface to a wall opening. Liquid water carried in the exhaust airflow can come into contact with the compensating device and collect there. The exhaust airflow carries the water to the outlet surface of the compensating device. The compensating device is structured and positioned to supply water to a wall opening, thereby achieving efficient water separation. On the one hand, the compensating device forms flow obstructions where the carried water may condense. At the same time, each flow obstruction creates flow resistance, resulting in pressure loss. However, due to the homogenizing effect of the compensating device, this pressure loss is more or less offset, and may even be excessively offset. Since the passable flow cross-section is larger downstream of the compensating device, flow velocity and friction losses are also reduced in this case. As a result, the exhaust airflow has a higher overall pressure level downstream of the compensator than upstream of it, so that the pressure loss caused by the compensator itself is offset, or even over-offset.

[0012] In the context of this application, "structure" corresponds to "configuration" and / or "apparatus," so the expression "structured in such a way" is synonymous with the expression "configured in such a way" and / or "adjusted in such a way."

[0013] In an advantageous development, the outlet surface may be located above the wall opening with respect to the housing height, or it may be coplanar with the wall opening. This makes it possible to supply water present on the outlet surface to the wall opening particularly easily and reliably.

[0014] In another development, the outflow surface may be specified to extend laterally with respect to the housing height and descend toward the wall opening. This allows water to be guided from the outflow surface to the wall opening using gravity. The compensation device may be structured flatly on the outflow surface.

[0015] In another developmental form, it is proposed that the compensator advantageously occupies the entire flowable cross-section of the chamber upstream of the wall opening. This prevents bypassing the compensator, and all exhaust airflow must pass through it. This increases the efficiency of the separation action and the homogenization effect of the compensator.

[0016] In a preferred embodiment, a deflection region may be formed within the chamber to create a flow curve and deflect the exhaust airflow. In particular, the deflection region can deflect the exhaust airflow about a deflection axis that can extend, for example, parallel to the longitudinal direction of the housing. Such a form of flow deflection generates an inertial force, which prevents the accompanying water from following the deflection as well as the exhaust airflow. Therefore, water may condense in the deflection region on the wall that defines the deflection region on the outer surface of the curve. The applicant's research has shown that non-uniform flow may be formed, particularly in the deflection region, based on the inertial action. The exhaust airflow is deflected about the deflection axis in the deflection region, and in regions relatively close to this deflection axis, relatively small volumetric flow rates or relatively small flow velocities occur. In contrast, in regions farther from the deflection axis, significantly high volumetric flow rates or significantly high flow velocities occur. As a result, the exhaust airflow is non-uniform in terms of velocity or volumetric flow rate per unit cross-section, transverse to the flow direction of the exhaust airflow within the deflection region. Now, a compensator can be placed in the deflection region and structured in particular to homogenize the exhaust airflow with respect to velocity. In this way, the compensator slows down the exhaust airflow with more flow resistance in the higher velocity region, which results in a pressure increase at the inlet surface of the compensator. This pressure increase at the inlet surface also leads to acceleration of the exhaust airflow in the lower velocity region. Here, since the flow resistance is also small due to the compensator, overall, when the compensator passes through the exhaust airflow, homogenization with respect to velocity occurs across the flowable cross-section of the deflection region downstream of the compensator. In other words, regions upstream of the compensator that previously featured lower flow velocities have higher flow velocities downstream of the compensator, and regions upstream of the compensator that previously featured higher flow velocities have lower flow velocities downstream of the compensator. Therefore, the flow across the passable cross-section of the deflection region downstream of the compensator is decelerated overall and has a more uniform velocity profile. Homogenization of the exhaust airflow allows for better utilization of the provided passable cross-section.Furthermore, speed and friction losses are also reduced, thus offsetting the pressure loss caused by the compensation device itself. More preferably, the wall opening may be located in the deflection region, thereby positioning the wall opening in a region where water is preferably separated.

[0017] In an advantageous embodiment, the deflection region is structured to deflect the exhaust airflow with respect to a deflection axis extending parallel to the longitudinal direction of the housing, in which case the wall opening may be specified to be adjacent to the compensator on the side away from the deflection axis. Additionally or alternatively, the compensator may be specified to be located within the housing between the deflection axis and the wall opening. Such measures optimize water separation and homogenization.

[0018] In addition to or alternatively to this, the flow resistance of the compensator may be further specified to increase as the distance from the deflection axis increases. The compensator has a constant flow resistance with respect to the exhaust airflow. The exhaust airflow has a non-uniform distribution of velocity in the deflection region, and the velocity of the exhaust airflow increases as the distance from the deflection axis increases. The increase in flow resistance as the distance from the deflection axis increases also counteracts the exhaust airflow in regions with higher velocity, thereby promoting the homogenization of the exhaust airflow.

[0019] Since the flow resistance is particularly related to the thickness of the compensator measured in the flow direction, it may be specifically determined that the thickness of the compensator in the housing height direction increases as the distance from the deflection axis increases.

[0020] In another development, the compensator may have a plurality of compensating passages through which exhaust air can flow parallel and which are particularly oriented parallel to each other, each of which has a flow resistance, a passage length measured in the direction of exhaust air flow, and a passage cross-section through which exhaust air can flow. In this case, the passage length corresponds in particular to the distance between the inlet and outlet surfaces of the compensator in each compensating passage. Advantageously, the compensator may now be structured such that the flow resistance of the compensating passages increases as the distance of the compensating passages from the deflection axis increases, in particular as the passage length of the compensating passages increases and / or the passage cross-section of the compensating passages decreases. As the passage length increases and the passage cross-section decreases, the flow resistance of each compensating passage increases. This promotes or causes a homogenizing effect of the compensator. In a simple embodiment, the passage cross-sections are the same size in all compensating passages, so that only the passage length of the discharge passages increases as the distance from the deflection axis increases. Embodiments of this type can be particularly easily manufactured. Alternatively, an embodiment can be considered in which the length of the discharge passage is the same in all compensation passages, so that as the distance from the deflection axis increases, only the cross-sectional area of ​​the discharge passage decreases. Similarly, a combined embodiment can be considered in which the length of the discharge passage increases as the distance from the deflection axis increases, and at the same time, as the distance from the deflection axis increases, the cross-sectional area of ​​the discharge passage decreases.

[0021] Advantageously, the compensating passages may extend parallel to each other. This results in homogenization with respect to the flow direction in the exhaust airflow downstream of the compensating device.

[0022] A structure in which the discharge passage extends parallel to the height direction of the housing is particularly advantageous. In this case, the exhaust airflow is homogenized parallel to the height direction of the housing, which in particular improves the flow of exhaust air to the exhaust air outlet.

[0023] In an advantageous embodiment, the deflection region may be structured to deflect the exhaust airflow by at least 45° with respect to a deflection axis extending parallel to the longitudinal direction of the housing, thereby structuring the exhaust airflow to flow in a direction away from the wall opening and the water collection chamber within the exhaust air outlet chamber. While gaseous exhaust airflow can easily follow this flow deflection, liquid water droplets carried in the exhaust airflow cannot follow such a flow deflection due to their greater mass. This promotes condensation of the carried water at the separation wall or side wall in the deflection region, thereby supplying a relatively large amount of water to the wall opening. In particular, the deflection region may be structured to deflect the exhaust airflow by substantially about 90° with respect to the deflection axis. For example, the exhaust airflow can flow toward the wall opening parallel to the lateral direction of the housing, and after deflection in the deflection region, flow toward the exhaust air outlet from the wall opening substantially parallel to the height direction of the housing.

[0024] In advantageous embodiments, the separation wall may extend in a curved manner in the deflection region to assist in the deflection of the exhaust airflow. The curved separation wall, or the curved section of the separation wall, promotes flow deflection with less resistance, which reduces pressure loss in the exhaust airflow when the air humidifier is passed through. For example, the separation wall may be curved toward the exhaust air outlet chamber in the deflection region.

[0025] In another advantageous embodiment, it is proposed that the separation wall has a distance measured in the housing height direction from the outlet surface of the humidifier block through which the dehumidified exhaust airflow flows out of the humidifier block. This distance may now increase along the outlet surface of the humidifier block in the direction of flow of the exhaust airflow within the exhaust air outlet chamber. In this way, the pressure drop or pressure loss in the exhaust airflow is reduced. The volume of the exhaust airflow increases in the direction of flow along the outlet surface of the humidifier block. Since the distance also increases along the outlet surface, more flowable cross-sections are provided for the increasing volumetric flow rate, thereby enabling a homogeneous exhaust airflow that is superior with a small pressure drop.

[0026] Further important features and advantages of the present invention are described in the dependent claims, the drawings, and the corresponding description of the drawings based on the drawings.

[0027] It should be understood that the features described above and the features further described below can be used not only in each combination described, but also in other combinations or alone without departing from the scope of the present invention. For example, the components described above and the components further described below of a higher unit such as a device, an apparatus, or an individually shown assembly can form separate components or elements of this unit, or can be an integrated area or section of this unit, even if they are shown in different forms in the drawings.

[0028] Preferred embodiments of the present invention are shown in the drawings and will be described in detail in the following description. In this case, the same reference signs are assigned to the same or similar or functionally identical components.

[0029] The drawings are each shown schematically.

Brief Description of the Drawings

[0030] [Figure 1] It is a schematic cross-sectional view showing a significant simplification of an air humidifier in the area of the water collection chamber. [Figure 2] In one embodiment, it is a diagram showing a schematic diagram in the form of a circuit diagram of a fuel cell system provided with an air humidifier. [Figure 3] In an alternative embodiment, it is a diagram showing a schematic diagram in the form of a circuit diagram of a fuel cell system provided with an air humidifier. [Figure 4] It is an isometric cross-sectional view showing an air humidifier in the turning area in an embodied embodiment. [Figure 5] It is an isometric cross-sectional view showing an air humidifier in the turning area in an embodied embodiment.

[0031] As shown in Figures 1 to 3, the air humidifier 1, used to transfer moisture from a humid exhaust airflow 3 to a dry supply airflow 2 for a fuel cell system 32 (simplified in Figures 2 and 3, particularly for an automobile not shown here), has a humidifier block 4 through which the exhaust airflow 3 and the supply airflow 2 of the fuel cell system 32 can pass with the medium separated. This humidifier block is structured so that moisture, i.e., water, is transferred from the exhaust airflow 3 to the supply airflow 2 as the humidifier block passes through it. The air humidifier 1 further has a housing 5 in which the humidifier block 4 is housed. As shown in Figures 1, 4 and 5, the housing 5 defines a housing longitudinal direction X, a housing lateral direction Y, and a housing height direction Z that extend perpendicularly to each other. In Figure 1, the housing longitudinal direction X is perpendicular to the plane of the figure. In Figures 1, 4, and 5, the lateral direction Y of the housing extends substantially horizontally, while the height direction Z of the housing extends substantially vertically.

[0032] According to Figures 2 and 3, the fuel cell system 32 has a fuel cell stack 33, to which a humidified supply airflow 2 is supplied during operation, and a moist exhaust airflow 3 is discharged from the fuel cell stack during operation.

[0033] As shown in Figures 1 to 3, the housing 5 has an exhaust air inlet 8 for supplying a humid exhaust airflow 3 to the humidifier block 4, an exhaust air outlet 9 for discharging the dehumidified exhaust airflow 3 from the humidifier block 4, a supply air inlet 6 for supplying a dry supply airflow 2 to the humidifier block 4, and a supply air outlet 7 for discharging the humidified supply airflow 2 from the humidifier block 4.

[0034] In the air humidifier 1 according to the present invention, a compensator 18 for homogenizing the exhaust airflow 3, through which the exhaust airflow 3 can pass, is arranged within the housing 5, as simply shown in Figures 1 to 4. According to Figure 2, the compensator 18 may be located within the housing 5, downstream of the humidifier block 4 with respect to the exhaust airflow 3, that is, between the humidifier block 4 and the exhaust air outlet 9 with respect to the flow direction of the exhaust airflow 3. Alternatively, according to Figure 3, the compensator 18 may be located within the housing 5, upstream of the humidifier block 4 with respect to the exhaust airflow 3, that is, between the humidifier block 4 and the exhaust air inlet 8 with respect to the flow direction of the exhaust airflow 3. In the examples of Figures 1, 4 and 5, the compensator 18 is located behind the humidifier block 4, that is, as shown in Figure 2, it is located within the housing 5 downstream of the humidifier block 4 with respect to the exhaust airflow 3.

[0035] In this case, the compensation device 18 shown in Figures 1 to 5 may be located within a chamber 11 through which the exhaust airflow 3 can pass, and may be structured to guide the liquid water present in the compensation device 18 to a wall opening 16 connecting this chamber 11 to the water collection chamber 12.

[0036] According to Figures 1, 2, 4, and 5, the chamber 11 in which the compensation device 18 is located may be an exhaust air outlet chamber, hereafter designated as 11'. The exhaust air outlet chamber 11' leads the exhaust air flow 3 from the humidifier block 4 and sends it to the exhaust air outlet 9. In this case, the liquid water in the humidifier block 4 is separated for the first time downstream of the humidifier block 4, so this liquid water can be used for moisture transfer to the supply air flow 2. In contrast, in the alternative embodiment shown in Figure 3, the chamber 11 in which the compensation device 18 is located may be an exhaust air supply chamber, hereafter designated as 11''. The exhaust air supply chamber 11'' leads the exhaust air flow 3 from the exhaust air inlet 8 and supplies it to the humidifier block 4. At this point, a particularly large amount of liquid water can be separated from the exhaust air flow 3. However, the configuration in which the compensation device 18 is located in the exhaust air outlet chamber 11', as shown in Figures 1, 2, 4, and 5, is preferred.

[0037] According to Figures 1, 4, and 5, the exhaust air outlet chamber 11' may be formed on the lower surface 10 of the housing 5 with respect to the housing height Z. Furthermore, a water collection chamber 12 is formed on the lower surface 10 of the housing 5, below the exhaust air outlet chamber 11' with respect to the housing height Z. This water collection chamber has a water outlet opening 13 and is separated from the exhaust air outlet chamber 11' by a separation wall 14. The exhaust air outlet chamber 11' has a deflection region 15 between the humidifier block 4 and the exhaust air outlet 9, which is structured for deflecting the exhaust air flow 3. In the embodiment shown herein, the exhaust air flow 3 flows substantially horizontally from left to right up to the deflection region 15. From the deflection region 15, the exhaust air flow 3 flows substantially vertically from bottom to top.

[0038] According to Figures 1, 4, and 5, the separation wall 14 has a wall opening 16 in the direction deflection region 15 that fluidly connects the water collection chamber 12 to the exhaust air outlet chamber 11'. When the air humidifier 1 is operating, the exhaust airflow 3 does not flow through the water collection chamber 12, thereby creating a dead space 17 in the area of ​​the wall opening 16. The water that condenses on the separation wall 14 is supplied to the wall opening 16 by the exhaust airflow 3 and reaches the water collection chamber 12 through this wall opening. This results in water separation 20. This water separation 20 or the supply of water to the water collection chamber 12 is indicated by arrows 20 in Figures 1, 4, and 5, respectively.

[0039] The exhaust air outlet chamber 11' is defined by a separation wall 14 in the housing height direction Z, below the humidification block 4 and on the inlet side in the deflection region 15. Furthermore, the exhaust air outlet chamber 11' is defined by a side wall 31 of the housing 5 in the deflection region 15 and in the portion that continues from this deflection region in the direction toward the exhaust air outlet 9, in the direction laterally with respect to the housing height direction Z, preferably in the housing lateral direction Y. Preferably, it may now be specified that a wall opening 16 is positioned within or along the separation wall 14 such that the wall opening 16 is adjacent to or defined by this side wall 31. This has the advantage that water collected at this side wall 31 can flow along the side wall 31 due to gravity and pass through the separation wall 16 into the water collection chamber 12.

[0040] The deflection region 15, in this case, deflects the exhaust airflow 3 by substantially about 90° with respect to a deflection axis 21 that extends parallel to the housing longitudinal direction X, thereby structuring the exhaust airflow 3 to flow in the exhaust air outlet chamber 11' away from the wall opening 16 and away from the water collection chamber 12. In the examples of Figures 1, 4, and 5, after its deflection, the exhaust airflow 3 flows substantially vertically upward from the wall opening 16. In the examples shown here, the flow deflection is directed counterclockwise with respect to the deflection axis 21.

[0041] Water separation 20 can already be achieved by the precise positioning and dimensional setting of the wall opening 16 in the deflection region 15. The compensation device 18 can significantly improve water separation 20.

[0042] According to Figures 1, 4, and 5, the compensator 18 may be positioned in the deflection region 15, may be passable to the exhaust airflow 3, and may be structured to homogenize the exhaust airflow 3. The compensator 18 has an inlet surface 19 through which the exhaust airflow 3 flows into the compensator 18, and an outlet surface 22 through which the exhaust airflow 3 flows out of the compensator 18. In this case, the compensator 18 is positioned in the deflection region 15 such that the outlet surface 22 guides the water present on the outlet surface 22 to the wall opening 16. Downstream of the compensator 18 or downstream of the deflection region 15, the compensator 18 homogenizes the exhaust airflow 3 with respect to the velocity distribution inside the flow cross-section of the exhaust air outlet chamber 11'. This makes it easier to separate water from the exhaust airflow 3. The water can collect at the outlet surface 22 and be guided from this outlet surface to the wall opening 16. The water reaches the water collection chamber 12 from the wall opening 16 by water separation 20.

[0043] The wall opening 16 is preferably adjacent to the compensator 18 on the side opposite to the deflection axis 21. Similarly, the compensator 18 may be located within the housing 5 between the deflection axis 21 and the wall opening 16. More preferably, the compensator 18 may be specified to be structured such that the flow resistance of the compensator 18 increases as the distance from the deflection axis 21 increases. For example, as shown in Figure 5, it can be specified that the thickness of the compensator 18 measured in the flow direction increases as the distance from the deflection axis 21 increases.

[0044] As shown in Figure 5, the compensator 18 is preferably positioned in the deflection region 15 such that the outlet surface 22 is located above the wall opening 16 with respect to the housing height direction Z, or is coplanar with the wall opening 16. This allows water flowing from the outlet surface 22 toward the wall opening 16 to flow into the wall opening 16 in a stepless and unobstructed manner, and thereby be discharged. In this example, the outlet surface 22 is flat and extends substantially laterally with respect to the housing height direction Z. In particular, the outlet surface 22 may be inclined with respect to the housing height direction Z at a relatively small incline, particularly less than 10°, such that the outlet surface 22 descends toward the wall opening 16. Furthermore, the compensator 18 may be configured to completely occupy the flowable cross-section of the exhaust air outlet chamber 11' upstream of the wall opening 16. This prevents leakage that bypasses the compensator 18.

[0045] As shown in Figure 5, the compensation device 18 has a plurality of compensation passages 23 through which exhaust air can flow parallel to each other. Each compensation passage 23 has a passage length 24 measured in the direction of exhaust air flow and a passage cross-section 25 through which air can flow. Because the compensation device 18 is oriented laterally with respect to the direction of exhaust air flow 3, each compensation passage 23 has a different spacing with respect to the deflection axis 21. According to the advantageous embodiment shown herein, it may be specified that the passage length 24 of the compensation passage 23 increases as the spacing of the compensation passage 23 from the deflection axis 21 increases. With respect to the curve produced by the deflection in the deflection region 15, as shown in Figure 5, the compensation passage 23 inside the curve is shorter than the discharge passage 23 outside the curve. In the example shown herein, the passage length 24 increases continuously or linearly with increasing spacing of the discharge passage 23 from the deflection axis 21. Similarly, the passage length 24 may increase progressively or retrogradely as the distance from the deflection axis 21 increases. In an alternative embodiment, it may be specified that the passage cross-section 25 of the discharge passage 23 decreases as the distance of the compensation passage 23 from the deflection axis 21 increases. In another embodiment, it may be specified that the passage length 24 of the compensation passage 23 increases while the passage cross-section 25 of the discharge passage 23 decreases as the distance of the discharge passage 23 from the deflection axis 21 increases. Similarly, there may be embodiments in which the passage length 24 and the passage cross-section 25 also increase or decrease as the distance from the deflection axis 21 increases, in which case the passage length 24 and the passage cross-section 25 are coordinated with each other such that the flow resistance increases as the distance from the deflection axis 21 increases.

[0046] In the example shown here, the compensation passages 23 are linear and parallel to each other and parallel to the housing height direction Z. Furthermore, since the inlet surface 19 and outlet surface 22 are formed flat and inclined relative to each other, the compensation device 18 has a wedge-shaped cross-section in the direction lateral to the housing longitudinal direction X.

[0047] As shown in Figures 1, 4, and 5, the separation wall 14 is preferably curved in at least the deflection region 15, so that the curved section 26 of the separation wall 14 assists in deflecting the exhaust air flow 3. In the illustrated example, the separation wall 14 is curved toward the exhaust air outlet chamber 11' in its curved section 26, i.e., in the deflection region 15.

[0048] According to Figures 1, 4, and 5, the separation wall 14 has a gap 28 measured in the housing height direction Z from the outlet surface 27 of the humidifier block 4 through which the dehumidified exhaust airflow 3 flows out of the humidifier block 4. In the example of Figure 1, this gap 28 is constant along the outlet surface 27 of the humidifier block 4 in the flow direction 29 of the exhaust airflow 3 within the exhaust air outlet chamber 11'. In the examples of Figures 1, 4, and 5, the flow direction 29 extends horizontally from left to right on the underside of the humidifier block 4. In contrast, in the examples of Figures 4 and 5, the separation wall 14 is molded or structured such that the gap 28 between the outlet surface 27 of the humidifier block 4 and the separation wall 14 increases along the outlet surface 27 in the flow direction 29. Within or along the deflection region 15, the gap 28 in Figures 4 and 5 reaches its maximum value, where the maximum volume flow of the exhaust airflow 3 exists. The exhaust air outlet chamber 11' is located downstream of the compensator 18 and is defined on one side by an intermediate wall 30 and on the other side by a side wall 31. The compensator 18 preferably occupies the entire flowable cross-section of the exhaust air outlet chamber 11'. For this purpose, the compensator 18 extends from the intermediate wall 30 to the separation wall 14, i.e., to a section 26 of the separation wall 14 adjacent to the wall opening 16. The wall opening 16 extends from the side wall 31 to the separation wall 14, i.e., to a section 26 of the separation wall 14 adjacent to the wall opening 16. [Explanation of symbols]

[0049] 1. Air humidifier 2. Supply airflow 3. Exhaust airflow 4 Humidifier Block 5 Housing 6. Air supply inlet 7. Supply air outlet 8. Exhaust air inlet 9. Exhaust air outlet 10 Underside of housing Room 11 12 Water collection chamber 13 Water Outlet Openings 14 Separation wall 15 Orientation area 16 Wall openings 17 Dead Space 18 Compensation device 19 Inflow surface 20 water separation 21. Directional axis 22 Outflow surface 23 Compensation Passage 24 aisle length 25 Cross-section of the passageway 26 categories 27 Outflow surface 28 intervals 29 Flow direction 30 Intermediate wall 31 Side wall 32 Fuel cell systems 33 Fuel cell stack

Claims

1. An air humidifier (1) for transferring moisture from a moist exhaust airflow (3) to a dry supply airflow (2), particularly for a fuel cell system in an automobile, The exhaust airflow (3) and the supply airflow (2) can be separated and passed through the medium, and a humidifier block (4) is provided to transfer moisture from the exhaust airflow (3) to the supply airflow (2) during this process. The housing (5) in which the humidifier block (4) is arranged has a housing vertical direction (X), a housing horizontal direction (Y), and a housing height direction (Z) that extend perpendicularly to each other, Equipped with, The housing (5) has an exhaust air inlet (8) for supplying the moist exhaust airflow (3) to the humidifier block (4), an exhaust air outlet (9) for leading out the dehumidified exhaust airflow (3) from the humidifier block (4), a supply air inlet (6) for supplying the dry supply airflow (2) to the humidifier block (4), and a supply air outlet (7) for leading out the humidified supply airflow (2) from the humidifier block (4). A compensating device (18) for homogenizing the exhaust airflow (3) is provided within the housing (5), through which the exhaust airflow (3) can flow. Air humidifier (1).

2. The air humidifier (1) according to claim 1, characterized in that the compensation device (18) is located in a chamber (11) through which the exhaust airflow (3) can flow, and is structured to guide the water present in the compensation device (18) to a wall opening (16) connecting the chamber (11) to a water collection chamber (12).

3. The air humidifier (1) according to claim 2, characterized in that the chamber (11) is an exhaust air outlet chamber (11') that leads out the exhaust air flow (3) from the humidifier block (4) and supplies it to the exhaust air outlet (9).

4. The air humidifier (1) according to claim 2, characterized in that the chamber (11) is an exhaust air supply chamber (11'') that leads out the exhaust air flow (3) from the exhaust air inlet (8) and supplies it to the humidifier block (4).

5. The compensation device (18) has an outlet surface (22), The compensation device (18) is positioned within the chamber (11) such that the outlet surface (22) guides the water present on the outlet surface (22) to the wall opening (16). An air humidifier (1) according to any one of claims 2 to 4, characterized in that

6. The air humidifier (1) according to claim 5, characterized in that the outflow surface (22) is located above the wall opening (16) with respect to the housing height direction (Z), or is in the same plane as the wall opening (16).

7. The air humidifier (1) according to claim 5 or 6, characterized in that the outlet surface (22) extends laterally with respect to the housing height direction (Z) and is inclined toward the wall opening (16).

8. The air humidifier (1) according to any one of claims 5 to 7, characterized in that the compensation device (18) is located upstream of the wall opening (16) and occupies the entire passable cross-section of the chamber (11).

9. The air humidifier (1) according to any one of claims 5 to 8, characterized in that the outlet surface (22) is flat.

10. The chamber (11) has a deflection region (15) that deflects the exhaust airflow (3), The wall opening (16) and the compensation device (18) are located in the deflection region (15). The air humidifier (1) according to claim 9, characterized in that...

11. The deflection region (15) is structured to deflect the exhaust airflow (3) with respect to a deflection axis (21) that extends parallel to the housing longitudinal direction (X), The wall opening (16) is adjacent to the compensation device (18) on the side opposite to the deflection axis (21). An air humidifier (1) according to claim 10, characterized in that...

12. The deflection region (15) is structured to deflect the exhaust airflow (3) with respect to a deflection axis (21) that extends parallel to the housing longitudinal direction (X), The compensation device (18) is located within the housing (5) between the deflection axis (21) and the wall opening (16). An air humidifier (1) according to claim 10 or 11, characterized in that...

13. The deflection region (15) is structured to deflect the exhaust airflow (3) with respect to a deflection axis (21) that extends parallel to the housing longitudinal direction (X), The current resistance of the compensation device (18) increases as the distance from the deflection axis (21) increases. An air humidifier (1) according to any one of claims 10 to 12, characterized in that

14. The compensation device (18) has a plurality of compensation passages (23) through which exhaust air can flow in parallel and which are oriented parallel to each other, and each of the compensation passages has a flow resistance, a passage length (24) measured in the flow direction of the exhaust air, and a passage cross-section (25) through which the exhaust air can flow, as described in any one of claims 1 to 13.

15. The deflection region (15) is structured to deflect the exhaust airflow (3) with respect to a deflection axis (21) that extends parallel to the housing longitudinal direction (X), The greater the distance of the compensation passage (23) from the deflection axis (21), the greater the flow resistance of the compensation passage (23). An air humidifier (1) according to any one of claims 14 and 10 to 13, characterized in that

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