CN211376822U - Hydrogen backflow system and check valve applied to same - Google Patents

Abstract

The utility model provides a hydrogen return-flow system and be applied to the check valve of this system, wherein, this system includes: a galvanic pile; the hydrogen input pipeline comprises a reflux driving branch, and the output end of the hydrogen input pipeline is connected with the input end of the galvanic pile and used for supplying hydrogen to the galvanic pile; the input end of the hydrogen return pipeline is connected with the output end of the galvanic pile, and the output end of the hydrogen return pipeline is connected with the return driving branch and used for converging the hydrogen which is not completely reacted in the galvanic pile to the hydrogen input pipeline; and the check valve is arranged on the hydrogen return pipeline. Can be through hydrogen input pipeline toward the pile input hydrogen, the pile is after reacting based on hydrogen, and pile exhaust hydrogen can flow through the check valve and converge to the hydrogen input pipeline again. Under the action of the check valve, the hydrogen is not discharged out of the reaction pipeline of the galvanic pile due to the exhaust of the galvanic pile, so that the part of the hydrogen can be reused by the galvanic pile, the hydrogen utilization rate is improved, and the loss is avoided.

Description

Hydrogen backflow system and check valve applied to same

Technical Field

The utility model relates to a fuel cell technical field especially relates to a hydrogen reflux system and be applied to the check valve of this system.

Background

The hydrogen side supply of the fuel cell for the current vehicle adopts a hydrogen reflux design, namely, hydrogen of the electric pile is supplied excessively, and residual hydrogen after reaction consumption reflows to the electric pile again. Also, the driving of the hydrogen back flow is mainly performed by a hydrogen driving apparatus, wherein the hydrogen driving apparatus includes: the hydrogen reflux pump is actively driven, and the ejector is passively driven. The hydrogen side of a common fuel cell is configured as shown in fig. 1, and the hydrogen reflux is driven by a reflux pump in fig. 1.

Furthermore, as shown in fig. 1, as the fuel cell electrochemical reaction continues to progress, nitrogen gas on the air side of the fuel cell unit reaction cells permeates to the hydrogen side through the proton exchange membrane and continues to accumulate, thereby hindering the hydrogen-oxygen electrochemical reaction of the fuel cell. In order to relieve the accumulation of nitrogen, an electric control tail exhaust valve is arranged in a hydrogen side system of the fuel cell, and the stack-out mixed gas is exhausted through a valve port when the tail exhaust valve is opened, so that the concentration of nitrogen in hydrogen is weakened. In addition, the instantaneous opening of the tail exhaust valve can generate high-flow-rate airflow flowing, the airflow can push liquid water in the flow channel, and the effect of assisting the water management of the fuel cell system can be achieved at the same time.

However, the tail exhaust valve is opened to generate a strong pressure relief effect instantaneously, so that the reverse flow of the air flow which flows to the inlet direction of the galvanic pile originally in the hydrogen return circuit is caused, and the air flow is directly exhausted through the tail exhaust valve. The hydrogen in the mixed gas discharged by the galvanic pile is not completely utilized and is wasted because the gas flow of the backflow part of the hydrogen backflow circuit does not pass through the galvanic pile.

SUMMERY OF THE UTILITY MODEL

In order to solve the above problem, the utility model provides a hydrogen reflux system and be applied to the check valve of this system, it has overcome above technical problem.

In order to achieve the above object, a first aspect of the present application provides a hydrogen gas recirculation system, the system comprising: a galvanic pile; the hydrogen input pipeline comprises a reflux driving branch, and the output end of the hydrogen input pipeline is connected with the input end of the galvanic pile and used for supplying hydrogen to the galvanic pile; the input end of the hydrogen return pipeline is connected to the output end of the galvanic pile, and the output end of the hydrogen return pipeline is connected to the return driving branch and used for converging hydrogen which is not completely reacted in the galvanic pile to the hydrogen input pipeline; and the check valve is arranged on the hydrogen return pipeline.

Optionally, the backflow driving branch comprises: the ejector is connected with a first input pipeline and a second input pipeline in parallel; wherein, the ejector sets up on the first input pipeline, moreover, the drainage inlet of ejector is connected in the check valve.

Optionally, the method further includes: and the first control valve is arranged on the first input pipeline, and is arranged at the upstream of the ejector.

Optionally, the method further includes: and the second control valve is arranged on the second input pipeline.

Optionally, the method further includes: the water diversion device is arranged on the hydrogen return pipeline and is arranged at the upstream of the check valve, and is used for separating the incompletely reacted hydrogen from the mixed gas discharged by the electric pile and inputting the incompletely reacted hydrogen to the check valve; and the discharge pipeline is connected with the water diversion device and used for discharging the gases except the incompletely reacted hydrogen in the mixed gas.

Optionally, the hydrogen input line includes: the output end of the hydrogen storage device is connected with the input end of the first input pipeline and the input end of the second input pipeline; and the pressure reducing valve is arranged on a pipeline section between the hydrogen storage device and the first input pipeline and the second input pipeline which are arranged in parallel.

A second aspect of the present application provides a check valve as described above, comprising: the axial section of the non-return pipeline is arranged in a frustum shape, and a first circulation pipeline and a second circulation pipeline are respectively connected to the end face with a larger area in the non-return pipeline and the end face with a smaller area in the non-return pipeline; the valve clack is fixed on the inner wall of the check pipeline, and a gap is formed between the outer surface of the valve clack and the inner wall of the check pipeline; the valve clack is arranged in a conical shape, the valve clack is coaxial with the check pipeline, and the bottom surface of the valve clack is inwards concave towards the top point of the valve clack to form a cambered surface; the bottom surface of the valve flap is disposed between the apex of the valve flap and the end surface of the check duct having a relatively small area.

Optionally, the method further includes: the fixing piece is arranged between the valve clack and the inner wall of the check pipeline and used for fixing the valve clack on the inner wall of the check pipeline.

Optionally, the area of the cross section of the first flow-through pipe is smaller than the area of the end face with larger area in the check pipe; the area of the cross section of the second circulation pipeline is larger than the area of the end face with the smaller area in the check pipeline.

Optionally, the check valve comprises: a fluid diode check valve.

The utility model has the advantages that: can be through hydrogen input pipeline toward the pile input hydrogen, the pile is after reacting based on hydrogen, and pile exhaust hydrogen can flow through the check valve and converge to the hydrogen input pipeline again. Under the action of the check valve, the hydrogen is not discharged out of the reaction pipeline of the galvanic pile due to the exhaust of the galvanic pile, so that the part of the hydrogen can be reused by the galvanic pile, the hydrogen utilization rate is improved, and the loss is avoided.

Drawings

The accompanying drawings, which form a part of the present application, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a prior art fuel cell hydrogen side architecture;

FIG. 2 is a schematic structural diagram of a hydrogen recirculation system according to an embodiment of the present invention;

fig. 3 is a schematic perspective view of a check valve according to an embodiment of the present invention;

FIG. 4 is a front view of a check valve in an embodiment of the present invention;

FIG. 5 is a schematic sectional view (one) of the check valve in the direction A-A according to the embodiment of the present invention;

FIG. 6 is a schematic sectional view (one) of the check valve in the direction A-A according to the embodiment of the present invention;

FIG. 7 is a streamline profile of the forward flow of the check valve in an embodiment of the present invention;

FIG. 8 is a flow direction distribution diagram of the reverse flow of the check valve in an embodiment of the present invention;

FIG. 9 is a schematic view of the hydrogen circulation path jet-flow transient flow without a check valve;

FIG. 10 is a schematic diagram of the hydrogen circulation path jet-drain transient flow with check valve.

Wherein, 1, hydrogen storage device; 2. a pressure reducing valve; 3. a first control valve; 4. a reflux pump; 5. a galvanic pile; 6. a reactor inlet air interface; 7. a stack outlet air interface; 8. a water diversion device; 9. a tail discharge valve; 10. a second control valve; 11. a check valve; 11a, check valve positive inlet; 11b, a flow guide structure support column cavity; 11c, a flow guide structure entity; 11d, a reverse flow conical transition zone; 11e, check valve reverse inlet; 11f, a reverse flow primary impingement zone; 11g, a reverse flow accelerated impingement zone; 11h, a mixed flow area; 12. an ejector; 12a, a jet inlet; 12b, a drainage inlet; 12c, an ejector outlet; 13. a valve flap; 141. a non-return duct; 142. a first circulation duct; 143. a second circulation duct; 15. a non-return duct; 16. a first circulation duct; 17. a second flow conduit.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

Unless specifically stated otherwise, the relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In order to facilitate understanding of the embodiments of the present invention, the structure of the present invention is explained in detail by several specific embodiments.

According to fig. 2, an embodiment of the present invention provides a hydrogen gas recirculation system, wherein the hydrogen gas recirculation system is a system architecture of a hydrogen side of a fuel cell, and the system includes: a galvanic pile 5, a hydrogen input line, a hydrogen return line and a check valve 11.

The electric stack 5 includes, but is not limited to, a hydrogen fuel cell, and in the present embodiment, the electric stack 5 is exemplarily configured as a hydrogen fuel cell, and the electric stack 5 is a battery manufactured to store energy using a chemical element, hydrogen.

Moreover, the hydrogen input pipeline includes a backflow driving branch, and an output end of the hydrogen input pipeline is connected to an input end of the stack 5, and in this embodiment, the hydrogen input pipeline is used for supplying hydrogen to the stack 5.

In this embodiment, the hydrogen return line is configured to merge hydrogen that is not completely reacted in the stack 5 to the hydrogen input line.

Of course, in this embodiment, an exhaust pipe is further provided on the hydrogen return line for discharging the mixture other than the returned hydrogen. The exhaust duct will be described below, and will not be described herein. Furthermore, a separator is provided on the hydrogen return line for separating hydrogen from the gas mixture discharged from the cell stack 5.

Further, the check valve 11 is provided in the hydrogen return line. Therefore, in the present embodiment, after the hydrogen discharged from the stack 5 flows through the check valve 11 and is merged to the input pipe, the hydrogen is not discharged out of the reaction pipe of the stack 5 due to the exhaust of the stack 5 by the check valve 11, so that the hydrogen can be reused by the stack 5, thereby avoiding loss. The check valve 11 allows the hydrogen gas discharged from the stack 5 to flow smoothly to the return driving branch, and prevents the flow of the hydrogen gas from the return driving branch in the direction passing through the check valve 11.

In addition, in the present embodiment, the specific result of the check valve 11 is not limited, and it is only necessary that it satisfies the requirements of the present embodiment.

In this regard, in this embodiment, hydrogen may be input to the stack 5 through the hydrogen input pipeline, and after the stack 5 reacts with hydrogen, the hydrogen discharged from the stack 5 flows through the check valve 11 and then flows into the hydrogen input pipeline. Under the action of the check valve 11, the hydrogen is not discharged out of the reaction pipeline of the galvanic pile 5 due to the exhaust of the galvanic pile 5, so that the part of the hydrogen can be reused by the galvanic pile 5, the hydrogen utilization rate is improved, and the loss is avoided.

In another embodiment, the backflow driving branch comprises: the ejector 12 is connected with a first input pipeline and a second input pipeline in parallel; wherein, the ejector 12 is arranged on the first input pipeline, and a drainage inlet of the ejector 12 is connected to the check valve 11.

In addition, in this embodiment, the hydrogen gas recirculation system further includes: a first control valve 3 and a second control valve 10. Wherein the first control valve 3 is arranged on the first input line, and wherein the first control valve 3 is arranged upstream of the ejector 12.

And the second control valve 10 is arranged on the second input line.

In the present embodiment, the first control valve 3 and the second control valve 10 may be both hydrogen control valves.

Specifically, in this embodiment, the drainage inlet 12b of the ejector 12 is connected to the check valve 11, the jet inlet 12a of the ejector 12 is connected to the first control valve 3, and the ejector outlet 12c of the ejector 12 is connected to the cell stack 5.

Also, the second input conduit acts as a jet bypass passage to accommodate the use of the eductor 12.

Namely: the specific structure of the hydrogen recirculation system in this embodiment is shown in fig. 2. Compared with the conventional fuel cell hydrogen side system architecture, in the embodiment, the hydrogen backflow is driven by the ejector 12, the check valve 11 is additionally arranged at the upstream of the drainage inlet 12b in the ejector 12, and a jet flow bypass channel formed by the second control valve 10 and the connecting pipeline is additionally arranged for being matched with the ejector 12.

Therefore, combine this check valve 11 and ejector 12, the hydrogen supply pressure of controlling ejector 12 upstream through first control valve 3 is not enough, leads to the efflux flow to supply under the condition lower and drainage effect weak, through the setting of this check valve 11 and ejector 12 to overcome the resistance of galvanic pile 5 exit through check valve 11, avoid the air current reverse flow in the hydrogen return line of the 5 entry directions of flow direction of original flow direction galvanic pile.

In another embodiment, for the separation device described above, one implementation manner is: and a water diversion device 8. Specifically, in the present embodiment, the water diversion device 8 is provided on the hydrogen return line, and the water diversion device 8 is provided upstream of the check valve 11. So that the water diversion device 8 can separate the incompletely reacted hydrogen from the mixed gas discharged from the electric pile 5 and input the incompletely reacted hydrogen to the check valve 11;

in addition, for the above exhaust duct, one implementation manner is as follows: a discharge line connected to the water diversion device 8 such that the discharge line is used to discharge the gas other than the incompletely reacted hydrogen in the mixed gas. Of course, in another embodiment, the drain line may also be used to drain the liquid drained by the stack 5.

In another embodiment, the hydrogen input line includes: the system comprises a hydrogen storage device 1 and a pressure reducing valve 2, wherein the output end of the hydrogen storage device 1 is connected with the input end of the first input pipeline and the input end of the second input pipeline; and the pressure reducing valve 2 is disposed on a pipe section between the hydrogen storage device 1 and the first input pipe and the second input pipe disposed in parallel.

In the present embodiment, one option of the hydrogen storage device 1 is: a hydrogen bottle.

In another embodiment, the check valve 11 includes: a fluid diode check valve 11.

In particular, in another embodiment, according to fig. 3-6, the check valve 11 comprises: a check duct 141 and a flap 13.

Wherein the axial section of the check pipe 141 is disposed in a frustum shape, and the end surface with a larger area in the check pipe 141 and the end surface with a smaller area in the check pipe 141 are respectively connected with the first circulation pipe 142 and the second circulation pipe 143;

in another embodiment, the cross-sectional area of the first flow-through channel 142 is smaller than the area of the larger-area end surface of the check channel 141; also, the area of the cross section of the second flow channel 143 is larger than the area of the end surface of the check channel 141 having a smaller area.

Wherein, the valve flap 13 is fixed on the inner wall of the check pipeline 141, and a gap exists between the outer surface of the valve flap 13 and the inner wall of the check pipeline 141; the valve clack 13 is arranged in a conical shape, the valve clack 13 is coaxial with the check pipeline 141, and the bottom surface of the valve clack 13 is inwards concave towards the vertex of the valve clack 13 to form an arc surface; the bottom surface of the valve flap 13 is provided between the apex of the valve flap 13 and the end surface of the check duct 141 having a small area.

In another embodiment, the check valve 11 further comprises: and a fixing member, which is disposed between the valve flap 13 and the inner wall of the check conduit 141, and is used to fix the valve flap 13 to the inner wall of the check conduit 141.

Specifically, the fixing member is exemplarily configured to be in a column-shaped configuration. Moreover, in the present embodiment, the outer surface area of the fixing member is set to be as small as possible on the basis of ensuring the fixing strength of the valve flap 13, and in the present embodiment, the specific shape, size or number of the fixing member is not limited as long as it satisfies the requirements of the present embodiment.

Also, according to fig. 5, the fixing member is provided in one piece in number, and the fixing member is fixed between the valve flap 13 and the inner wall of the check duct 141.

Of course, according to fig. 6, the fixture is arranged as follows: the number of the fixing members is set to two, and the two fixing members are coaxially disposed and fixed to both sides of the valve flap 13, respectively, and of course, each fixing member is fixed between the valve flap 13 and the inner wall of the check duct 141.

Of course, the above-mentioned fixing member is integrally formed with the valve flap 13.

In the hydrogen backflow system and the structure of the check valve 11, the inner cavity of the check pipe of the check valve 11 is in the structure of the fluid diode check valve 11, and as shown in fig. 3-6, the check pipe of the check valve 11 is provided with a check valve forward inlet 11a, a check valve reverse inlet 11e, and a cylinder 11b (i.e., the above-mentioned fixing member) for supporting the flow guiding structure. The inner cavity of the check pipeline of the check valve 11 is provided with targeted flow optimization according to the flow state of a target working condition point on the hydrogen side of the fuel cell, the conical airflow at the head part of the flow guide structure is guided in the forward flow stage of the airflow, and in the reverse flow stage of the airflow, a reverse flow primary impact area 11f and a reverse flow accelerating impact area 11g are formed by the reverse flow conical transition area 11d and the tail area of the flow guide structure entity 11c, and a mixed flow area 11h is formed on the side surface with the larger cross section area in the check pipeline. Thereby serving to attenuate reverse flow.

Adopt 11 structures of check valve among this technical scheme and through size optimization, realize that 11 forward flow of check valve is unobstructed, the effect that backward flow stops.

Wherein, fig. 7 is a result of analysis of the distribution of the forward flow streamline of the check valve 11 at the small electric density working point of the hydrogen reflux system of the fuel cell; fig. 8 shows the analysis result of the distribution of the forward flow streamline of the check valve 11 at the small electric density operating point of the hydrogen backflow system of the fuel cell, and the reverse flow loss of the check valve 11 is about 5 times of the forward flow loss under the same hydrogen flow rate.

The hydrogen gas recirculation system and the check valve 11 applied to fig. 2 are directed to the evaluation of the recirculation effect in suppressing pulse injection. The analysis results of fig. 9 and 10 compare each other, and the reflux amount in the pulse jet low flow rate supply stage is reduced by nearly 2 times. Reflux at low flow rates in the ejector 12 pulse ejection strategy is not completely avoided, but is significantly reduced.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, low" etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a contrary explanation, these orientation words do not indicate and imply that the system or element in question must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be interpreted as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and if not stated otherwise, the terms have no special meaning, and therefore, the scope of the present invention should not be construed as being limited.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A hydrogen recirculation system, comprising:

a galvanic pile;

the hydrogen input pipeline comprises a reflux driving branch, and the output end of the hydrogen input pipeline is connected with the input end of the galvanic pile and used for supplying hydrogen to the galvanic pile;

the input end of the hydrogen return pipeline is connected to the output end of the galvanic pile, and the output end of the hydrogen return pipeline is connected to the return driving branch and used for converging hydrogen which is not completely reacted in the galvanic pile to the hydrogen input pipeline;

and the check valve is arranged on the hydrogen return pipeline.

2. A hydrogen recirculation system as claimed in claim 1, wherein the recirculation drive branch comprises: the ejector is connected with a first input pipeline and a second input pipeline in parallel;

wherein, the ejector sets up on the first input pipeline, moreover, the drainage inlet of ejector is connected in the check valve.

3. The hydrogen recirculation system according to claim 2, further comprising:

and the first control valve is arranged on the first input pipeline, and is arranged at the upstream of the ejector.

4. The hydrogen recirculation system according to claim 2, further comprising:

and the second control valve is arranged on the second input pipeline.

5. The hydrogen recirculation system according to claim 1, further comprising:

the water diversion device is arranged on the hydrogen return pipeline and is arranged at the upstream of the check valve, and is used for separating the incompletely reacted hydrogen from the mixed gas discharged by the electric pile and inputting the incompletely reacted hydrogen to the check valve;

and the discharge pipeline is connected with the water diversion device and used for discharging the gases except the incompletely reacted hydrogen in the mixed gas.

6. A hydrogen recirculation system as claimed in claim 2, characterized in that said hydrogen input line comprises:

the output end of the hydrogen storage device is connected with the input end of the first input pipeline and the input end of the second input pipeline;

and the pressure reducing valve is arranged on a pipeline section between the hydrogen storage device and the first input pipeline and the second input pipeline which are arranged in parallel.

7. A check valve for a hydrogen gas recirculation system, characterized in that the check valve is as described in any one of claims 1 to 6, and comprises:

the axial section of the non-return pipeline is arranged in a frustum shape, and a first circulation pipeline and a second circulation pipeline are respectively connected to the end face with a larger area in the non-return pipeline and the end face with a smaller area in the non-return pipeline;

the valve clack is fixed on the inner wall of the check pipeline, and a gap is formed between the outer surface of the valve clack and the inner wall of the check pipeline;

the valve clack is arranged in a conical shape, the valve clack is coaxial with the check pipeline, and the bottom surface of the valve clack is inwards concave towards the top point of the valve clack to form a cambered surface;

the bottom surface of the valve flap is disposed between the apex of the valve flap and the end surface of the check duct having a relatively small area.

8. The check valve of claim 7, further comprising:

the fixing piece is arranged between the valve clack and the inner wall of the check pipeline and used for fixing the valve clack on the inner wall of the check pipeline.

9. The check valve of claim 7, wherein the cross-section of the first flow passage has an area that is smaller than the area of the larger-area end face of the check passage;

the area of the cross section of the second circulation pipeline is larger than the area of the end face with the smaller area in the check pipeline.

10. The check valve of claim 7, comprising: a fluid diode check valve.

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