Stack Manifold

Abstract

To provide a stack manifold which makes unevenness of a fluid flowing out from multiple lead-out ports to a cell stack less likely to occur without increasing its size.SOLUTION: A stack manifold 3 may be attached to a cell stack 1 formed by overlapping multiple fuel battery cells 2 in a thickness direction. The stack manifold 3 includes a housing 4 formed with multiple introduction ports 5, a distribution chamber 6, and multiple lead-out ports 7. The stack manifold 3 leads out a fluid introduced from the introduction ports 5 into the distribution chamber 6 from the distribution chamber 6 to the cell stack 1 through the lead-out ports 7. The introduction ports 5 are formed so that directions of the fluid flowing into the distribution chamber 6 are different from each other.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a stack manifold for supplying fluid to a cell stack of a fuel cell. [Background technology]

[0002] As shown in Patent Document 1, a stack manifold can be attached to a cell stack of a fuel cell. The stack manifold includes a housing. The housing is formed with a plurality of inlets, a distribution chamber, and a plurality of outlets. The stack manifold discharges fluid introduced from the inlet of the housing to the distribution chamber from the distribution chamber to the cell stack via the outlets. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-117550 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the stack manifold of Patent Document 1, the multiple inlets are simply formed at equal intervals, so when a fluid is introduced into a distribution chamber from the multiple inlets and flows to the multiple outlets, the fluid does not necessarily flow evenly through those inlets. If the fluid does not flow evenly through the multiple outlets in the stack manifold, the discharge of the fluid from those outlets to the cell stacks will be biased.

[0005] Increasing the volume of the distribution chamber in the stack manifold makes it difficult for the flow of fluid introduced into the distribution chamber from the multiple inlets to become biased within the distribution chamber. As a result, the fluid flows more easily from the distribution chamber to the multiple outlets without bias, and the fluid is less likely to be discharged from the outlets to the cell stacks biased. However, in this case, the volume of the distribution chamber must be increased, and the stack manifold becomes larger. [Means for solving the problem]

[0006] The means for solving the above problems and their effects will be described below. A stack manifold that solves the above problem can be attached to a cell stack formed by stacking a plurality of fuel cell units in a thickness direction. The stack manifold includes a housing in which a plurality of inlets, a distribution chamber, and a plurality of outlets are formed. The stack manifold discharges fluid introduced from the inlets into the distribution chamber from the distribution chamber through the outlet to the cell stack. The plurality of inlets are formed so that the fluid flows into the distribution chamber in mutually different directions.

[0007] According to the above configuration, since the inlet ports have different fluid inflow directions into the distribution chamber, the fluids introduced into the distribution chamber from the inlets collide with each other or with the inner wall of the housing, which tends to disturb the flow of the fluid in the distribution chamber. As a result, the flow of the fluid from the distribution chamber to the outlet ports is less likely to be biased, and it is possible to suppress the fluid from being discharged from the outlet ports to the cell stack from being uniformly discharged. In addition, by disturbing the flow of the fluid in the distribution chamber, the flow of the fluid from the distribution chamber to the outlet ports is less likely to be biased, so there is no need to increase the volume of the distribution chamber to prevent such bias. Therefore, the stack manifold does not become larger in size as the distribution chamber is enlarged. [Brief description of the drawings]

[0008] [Figure 1]2 is a schematic diagram showing a cell stack and a stack manifold of the fuel cell of the present embodiment. [Diagram 2] 1 is a schematic diagram showing a comparative example of a stack manifold. [Diagram 3] 13 is a schematic diagram showing another example of a stack manifold. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, one embodiment of a stack manifold applied to a fuel cell will be described with reference to FIGS. As shown in Fig. 1, a fuel cell stack 1 is formed by stacking a plurality of fuel cells 2 in the thickness direction. Fluids such as fuel gas (hydrogen, etc.), oxidizing gas (air, etc.), and coolant (cooling water, etc.) are supplied to and discharged from the cell stack 1. The fuel gas and oxidizing gas are supplied to the cell stack 1, and electricity is generated based on a reaction between the fuel gas and the oxidizing gas in a membrane electrode gas-diffusion assembly (MEGA) of the fuel cell 2. Heat generated during this power generation is removed by the coolant passing through the cell stack 1. As a result, the cell stack 1 is cooled.

[0010] A stack manifold 3 can be attached to the cell stack 1. This stack manifold 3 is for supplying fluids such as the above-mentioned fuel gas, oxidizing gas, and refrigerant to the cell stack 1. The stack manifold 3 in this example supplies, for example, fuel gas to the cell stack 1. The stack manifold 3 has a housing 4. The housing 4 is formed with a plurality of inlets 5, a distribution chamber 6, and a plurality of outlets 7. The stack manifold 3 discharges a fluid (fuel gas in this example) introduced from the inlet 5 of the housing 4 to the distribution chamber 6 from the distribution chamber 6 via the outlet 7 to the cell stack 1.

[0011] The multiple outlets 7 in the stack manifold 3 are formed so that their center lines L1 are parallel to one another. The multiple inlets 5 in the stack manifold 3 are formed so that the directions in which the fluid flows into the distribution chamber 6 are different from one another. More specifically, the multiple inlets 5 are formed so that imaginary lines L2 extending from the multiple inlets 5 toward the inside of the distribution chamber 6 intersect within the distribution chamber 6. Furthermore, at least one of the multiple inlets 5 (all of them in this example) has a center line L3 inclined with respect to the center line L1 of the outlet 7.

[0012] Next, the operation of the stack manifold 3 of this embodiment will be described. In a stack manifold 3 attached to a cell stack 1, the fluid is introduced into a distribution chamber 6 in a housing 4 through a plurality of inlets 5. The fluid is then discharged from the distribution chamber 6 to the cell stack 1 through a plurality of outlets 7.

[0013] Since the multiple inlets 5 have mutually different fluid inflow directions into the distribution chamber 6, the fluids introduced into the distribution chamber 6 from the multiple inlets 5 collide with each other or with the inner wall of the housing 4, which tends to disturb the flow of the fluid in the distribution chamber 6. As a result, the flow of the fluid from the distribution chamber 6 to the multiple outlets 7 is less likely to be uneven, and it is possible to suppress the fluid from being unevenly discharged from the outlets 7 to the cell stack 1.

[0014] 2 shows an example in which the volume of the distribution chamber 6 in the stack manifold 3 is increased in order to prevent bias in the flow of the fluid from the distribution chamber 6 to the multiple outlets 7. In this case, by enlarging the distribution chamber 6 in the direction of arrow t1, the distance from the inlet 5 to the outlet 7 becomes longer, so that bias in the flow of the fluid is less likely to occur when the fluid passes through the distribution chamber 6. However, the stack manifold 3 becomes larger in size because the volume of the distribution chamber 6 is increased.

[0015] In the stack manifold 3 (FIG. 1) of this embodiment, by generating turbulence in the flow of the above-mentioned fluid in the distribution chamber 6, the flow of the above-mentioned fluid from the distribution chamber 6 to the multiple outlets 7 is less likely to be biased, so there is no need to increase the volume of the distribution chamber 6 to prevent such bias from occurring. This makes it possible to prevent the distribution chamber 6 from becoming larger in the direction of arrow t2 in FIG. 1, and to prevent the stack manifold 3 from becoming larger in size as the distribution chamber 6 is enlarged.

[0016] According to the present embodiment described above in detail, the following effects can be obtained. (1) The stack manifold 3 does not need to be large, and uneven discharge of fluid from the multiple outlets 7 to the cell stacks 1 can be prevented.

[0017] (2) In the stack manifold 3, imaginary lines L2 that are formed by assuming that the multiple inlets 5 are extended into the distribution chamber 6 intersect within the distribution chamber 6. That is, the multiple inlets 5 are formed in the housing 4 in this manner. For this reason, the fluids introduced into the distribution chamber 6 from the multiple inlets 5 collide with each other, which efficiently disturbs the flow of the fluid within the distribution chamber 6. As a result, the flow of the fluid from the distribution chamber 6 to the multiple outlets 7 is less likely to be biased, and bias in the discharge of the fluid from the outlets 7 to the cell stack 1 can be suppressed.

[0018] (3) At least one (all in this example) of the multiple inlets 5 in the stack manifold 3 has a center line L3 of the inlet 5 inclined relative to the center line L1 of the outlet 7. For this reason, the fluid introduced into the distribution chamber 6 from the inlet 5 having a center line L1 inclined relative to the center line L1 of the outlet 7 is unlikely to be discharged from the outlet 7 immediately after being introduced into the distribution chamber 6. For this reason, the flow of the fluid in the distribution chamber 6 is likely to become turbulent. As a result, the flow of the fluid from the distribution chamber 6 to the multiple outlets 7 is unlikely to become uneven, and uneven discharge of the fluid from those outlets 7 to the cell stack 1 can be suppressed.

[0019] The above embodiment can be modified, for example, as follows: The above embodiment and the following modified examples can be combined with each other to the extent that no technical contradiction occurs. It is not necessary that the center lines L3 of all of the plurality of inlets 5 are inclined with respect to the center line L1 of the outlets 7.

[0020] The imaginary lines L2 (FIG. 1) drawn when the multiple inlets 5 are assumed to extend into the distribution chamber 6 do not necessarily need to intersect within the distribution chamber 6. As shown in FIG. 3, at least one of the multiple inlets 5 (two in this example) may be formed to open toward an outlet 7 located at a location among the multiple outlets 7 where the fluid does not flow well, for example, an outlet 7 located at a corner of the distribution chamber 6. In this case, the fluid introduced into the distribution chamber 6 from the inlet 5 that opens toward the outlet 7 located at a location among the multiple outlets 7 where the fluid does not flow well can be made to flow toward the outlet 7 located at the location where the fluid does not flow well. This makes it possible to prevent uneven discharge of the fluid from the multiple outlets 7 to the cell stack 1. Furthermore, it is not necessary to increase the volume of the distribution chamber 6 to prevent such uneven discharge. This makes it possible to prevent the distribution chamber 6 from becoming larger in the direction of the arrow t2 in FIG. 3.

[0021] The number of the multiple inlets 5 may be changed appropriately, for example, to four or more. [Explanation of symbols]

[0022] 1...Cell stack 2...Fuel cell 3…Stack manifold 4. Housing 5...Entrance 6…Distribution room 7... Outlet

Claims

1. A stack manifold that can be attached to a cell stack formed by stacking a plurality of fuel cells in a thickness direction, the stack manifold comprising a housing having a plurality of inlets, a distribution chamber, and a plurality of outlets, and that discharges a fluid introduced from the inlets into the distribution chamber from the distribution chamber through the outlets to the cell stack, A stack manifold in which the multiple inlets are formed so that the flow directions of the fluid into the distribution chamber are different from each other, and virtual lines extending from the multiple inlets toward the distribution chamber intersect within the distribution chamber.

2. 2. The stack manifold according to claim 1, wherein a center line of at least one of the plurality of inlets is inclined with respect to a center line of the outlet.

3. 3. The stack manifold according to claim 1, wherein at least one of the plurality of inlets is open toward one of the plurality of outlets that is located at a corner of the distribution chamber.

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