Tail discharge hydrogen concentration testing device of gas-water separator of fuel cell

Abstract

The utility model provides a tail discharge hydrogen concentration testing device of a fuel cell gas-water separator, and relates to the technical field of hydrogen concentration detection, the tail discharge hydrogen concentration testing device comprises a tail discharge main pipeline and a tail discharge branch, the tail discharge branch comprises a branch first gas inlet pipeline and a branch second gas inlet pipeline; the branch first air inlet pipeline and the branch second air inlet pipeline are connected with the tail exhaust main pipeline; a gas circulating pump is arranged on the first branch gas inlet pipeline, and the gas inlet section of a gas inlet of the second branch gas inlet pipeline is larger than the pipeline gas flowing section of the second branch gas inlet pipeline; an outlet of the tail exhaust branch is connected with the tail exhaust main pipeline, and a venturi structure is arranged at the joint of the outlet of the tail exhaust branch and the tail exhaust main pipeline. The problems that due to the fact that a tail exhaust branch is long and thin and large in flow resistance, when air is introduced, mixed gas extracted by a Venturi structure from a main pipeline is insufficient, and testing of a hydrogen concentration sensor is affected are solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydrogen concentration detection, and particularly relates to a tail hydrogen concentration testing device of a fuel cell gas-water separator. BACKGROUND

[0002] Hydrogen and oxygen are mainly used as reaction gases in a fuel cell, and the unreacted hydrogen is mixed with air and discharged through a tail exhaust pipeline while generating electric energy through chemical reactions inside the fuel cell. Hydrogen is flammable and explosive, and has an explosion risk when the volume concentration in air is between 4% and 75%. Therefore, the hydrogen concentration in the tail exhaust gas of the fuel cell system needs to be monitored in real time to ensure that the hydrogen concentration in the tail exhaust is within a safe range.

[0003] Due to the characteristics of the fuel cell, a large amount of heat and water is generated while generating electric energy through chemical reactions, so the tail exhaust gas is in a high-temperature and high-humidity state and contains some liquid water. Such high-temperature and high-humidity gas can affect the detection results of the hydrogen concentration sensor and reduce the service life of the sensor, so it is necessary to reduce the humidity of the tail exhaust gas to avoid condensation of liquid water when passing through the hydrogen concentration sensor.

[0004] In the patent CN211530092U, a Venturi structure is used to extract the tail exhaust main pipeline mixed gas, and air is used to cool the gas-water separator to reduce the temperature and humidity of the mixed gas. However, the air cooling effect is poor, and the cooling effect on the gas-water separator is limited. In addition, due to the large flow resistance of the tail exhaust branch, the introduction of air will cause insufficient extraction of the main pipeline mixed gas by the Venturi structure, affecting the hydrogen concentration sensor test. UTILITY MODEL CONTENT

[0005] The application provides a tail hydrogen concentration testing device of a fuel cell gas-water separator to solve the problem that due to the large flow resistance of the tail exhaust branch, the introduction of air will cause insufficient extraction of the main pipeline mixed gas by the Venturi structure, affecting the hydrogen concentration sensor test.

[0006] The technical scheme adopted by the application is as follows:

[0007] The application provides a tail hydrogen concentration testing device of a fuel cell gas-water separator, which comprises a tail exhaust main pipeline and a tail exhaust branch, wherein the tail exhaust branch comprises a branch first gas inlet pipeline and a branch second gas inlet pipeline; the branch first gas inlet pipeline and the branch second gas inlet pipeline are connected with the tail exhaust main pipeline; a gas circulation pump is arranged on the branch first gas inlet pipeline, and the gas inlet cross section of the branch second gas inlet pipeline is larger than the pipeline gas flow cross section of the branch second gas inlet pipeline; the outlet of the tail exhaust branch is connected with the tail exhaust main pipeline, and a Venturi structure is arranged at the connection.

[0008] The fuel cell gas-water separator and tail exhaust hydrogen concentration testing device provided by the application further comprises the following additional technical features: the gas-water separator, the PTC heating sheet and the hydrogen concentration sensor are arranged on the branch first air inlet pipe, and the hydrogen concentration sensor is arranged at the corner of the tail exhaust branch.

[0009] According to one embodiment of the application, the gas-water separator comprises a gas-water separator cavity, a gas-water separator outer wall and a cooling water flow channel; the gas-water separator cavity is a cylindrical cavity, the cooling water flow channel is arranged around the gas-water separator cavity, and the outer side of the cooling water flow channel is the gas-water separator outer wall.

[0010] According to one embodiment of the application, the gas-water separator cavity comprises a gas inlet, a gas outlet, a cavity bottom and a baffle; the cavity bottom is provided with a baffle drain port, and the cavity bottom is arranged in an inclined manner with an inclination angle of 1°-2°; the baffles are arranged in an interlaced manner in the gas-water separator cavity.

[0011] According to one embodiment of the application, the cross section of the cooling water flow channel is circular, and the cooling water flow channel is arranged in a spiral structure in the gas-water separator outer wall.

[0012] According to one embodiment of the application, the inlet and outlet of the cooling water flow channel are arranged opposite to the gas inlet and the gas outlet, so that the overall advancing direction of the cooling water in the cooling water flow channel is opposite to the overall flow direction of the tail exhaust gas of the branch first air inlet pipe.

[0013] According to one embodiment of the application, the gas circulating pump is used for gas extraction, and the gas circulating pump includes but is not limited to a vortex type, a Roots type and a centrifugal type.

[0014] According to one embodiment of the application, the PTC heating sheet is arranged in front of the hydrogen concentration sensor, and the PTC heating sheet is used for heating gas, increasing the temperature of the gas and reducing the humidity of the gas.

[0015] According to one embodiment of the application, the PTC heating sheet is wrapped on the tail exhaust branch.

[0016] According to one embodiment of the application, the PTC heating sheet is arranged in front of the gas-water separator, and the gas-water separator is used for reducing the temperature of the tail exhaust mixed gas when passing through.

[0017] Thanks to the above technical solutions, the application has the following beneficial effects:

[0018] The branch first air inlet pipeline and the branch second air inlet pipeline are connected with the tail exhaust main pipeline; a gas circulating pump is arranged on the branch first air inlet pipeline, and the gas inlet of the branch second air inlet pipeline has an air inlet section larger than a pipeline gas flow section of the branch second air inlet pipeline, so that the inlet area is enlarged, the gas flow into the tail exhaust branch is increased, and the gas taking effect is enhanced; the outlet of the tail exhaust branch is connected with the tail exhaust main pipeline, and a Venturi structure is arranged at the connection position. The tail exhaust gas taking part simultaneously uses the gas circulating pump and the Venturi structure, so as to ensure the gas taking effect; when the tail exhaust flow is small, the gas circulating pump can be started to ensure the tail exhaust branch flow; when the tail exhaust flow is large, the gas circulating pump can be closed or the rotating speed of the gas circulating pump is reduced, and the Venturi structure is mainly used to take the tail exhaust gas from the tail exhaust main pipeline, so that the energy consumption is reduced, and the test accuracy of the hydrogen concentration sensor is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and serve to explain the principles of the application, and do not limit the application in any way. In the drawings:

[0020] Fig. 1 A structure schematic diagram of a tail exhaust hydrogen concentration test device of a fuel cell gas-water separator provided by the embodiment of the application;

[0021] Fig. 2 A front view of the gas-water separator provided by the embodiment of the application;

[0022] Fig. 3 A top view of the gas-water separator provided by the embodiment of the application;

[0023] Fig. 4 A left view of the gas-water separator provided by the embodiment of the application;

[0024] Fig. 5 A sectional view of the gas-water separator in the A-A direction provided by the embodiment of the application;

[0025] Fig. 6 A sectional view of the gas-water separator in the B-B direction provided by the embodiment of the application.

[0026] Among them,

[0027] 1 - tail exhaust main pipe, 2 - tail exhaust branch pipe, 3 - gas-water separator, 4 - PTC heating sheet, 5 - hydrogen concentration sensor, 6 - gas circulating pump, 7 - venturi structure, 21 - first intake pipe of branch, 22 - second intake pipe of branch, 221 - gas inlet of second intake pipe of branch, 23 - tail exhaust branch pipe outlet, 31 - gas inlet, 32 - gas outlet, 33 - water outlet, 34 - cooling water inlet, 35 - cooling water outlet, 36 - outer wall of gas-water separator, 37 - cavity of gas-water separator, 38 - cooling water flow channel, 39 - baffle, 40 - baffle water hole, 41 - bottom surface of cavity. DETAILED DESCRIPTION

[0028] In order to more clearly illustrate the overall concept of the present application, the following will be described in detail with reference to the accompanying drawings.

[0029] In the following description, a lot of specific details are set forth in order to fully understand the present application, but the present application can also be implemented in other ways different from those described herein, therefore, the protection scope of the present application is not limited by the specific embodiments disclosed below. It should be noted that the embodiments of the present application and the features in each embodiment can be combined with each other without conflict.

[0030] In addition, in the description of the present application, it should be understood that the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation to the present application.

[0031] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection, or communication; it can be directly connected, or indirectly connected through intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0032] In this application, unless otherwise explicitly specified and limited, a first feature is "on" or "under" a second feature can mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. In the description of the specification, the description referring to the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0033] As shown in Figs. 1 to 3 The tail exhaust hydrogen concentration testing device for fuel cell gas-water separator 3 provided by the embodiments of the present application comprises: a tail exhaust main pipeline 1 and a tail exhaust branch pipeline 2, the tail exhaust branch pipeline 2 comprises a branch first gas inlet pipeline 21 and a branch second gas inlet pipeline 22; the branch first gas inlet pipeline 21 and the branch second gas inlet pipeline 22 are connected with the tail exhaust main pipeline 1; a gas circulating pump 6 is arranged on the branch first gas inlet pipeline 21, and the gas inlet section of the branch second gas inlet pipeline gas inlet 221 is larger than the pipeline gas flow section of the branch second gas inlet pipeline 22; a tail exhaust branch outlet 23 is connected with the tail exhaust main pipeline 1, and a Venturi structure 7 is arranged at the connection.

[0034] Specifically, the tail exhaust main pipeline 1 is the main channel for tail exhaust gas in the fuel cell system, which is responsible for discharging the hydrogen and other gases that do not participate in the reaction from the fuel cell stack.

[0035] The tail exhaust branch pipeline 2

[0036] The tail exhaust branch pipeline 2 is a branch pipeline from the tail exhaust main pipeline 1, which is used to guide a part of the tail exhaust gas to the hydrogen concentration testing device for detection. This branch pipeline comprises two gas inlet pipelines, i.e., the branch first gas inlet pipeline 21 and the branch second gas inlet pipeline 22.

[0037] The branch first gas inlet pipeline 21

[0038] The branch first gas inlet pipeline 21 is connected with the tail exhaust main pipeline 1, and a gas circulating pump 6 is arranged thereon. The gas circulating pump 6 is used to extract the tail exhaust gas at low flow rate, so as to ensure that sufficient gas flow rate reaches the testing device.

[0039] The branch second gas inlet pipeline 22

[0040] The branch second gas inlet pipeline 22 is also connected with the tail exhaust main pipeline 1, and the gas inlet 31 thereof is designed in a horn shape, and the gas inlet section is larger than the flow section inside the pipeline, so that the gas flow rate entering the branch pipeline can be increased.

[0041] Venturi structure 7

[0042] The venturi structure 7 is located at the connection between the tail exhaust branch outlet 23 and the tail exhaust main pipeline 1. The venturi structure 7 is a fluid mechanics element that accelerates fluid flow through a narrow throat, reducing local pressure, thereby attracting more gas into the branch. At high flow rates, the gas circulation pump 6 can be turned off or its speed reduced, and the venturi effect can be used to extract gas, thereby saving energy.

[0043] Working principle

[0044] At low flow rates, the gas circulation pump 6 is turned on to ensure sufficient gas flow into the tail exhaust branch 2 for testing. At high flow rates, the gas circulation pump 6 can be turned off or its speed reduced, and the negative pressure effect generated by the venturi structure 7 is relied on to extract gas, thereby reducing energy consumption. The horn-shaped design of the branch second inlet pipeline 22 helps to increase the gas flow into the branch.

[0045] This design combines the advantages of the gas circulation pump 6 and the venturi structure 7, ensuring testing accuracy under different flow conditions and minimizing energy consumption as much as possible. At low flow rates, the gas circulation pump 6 assists in gas extraction, and at high flow rates, the venturi effect is relied on more, thereby optimizing the operating efficiency of the entire system.

[0046] The tail exhaust hydrogen concentration test device for a fuel cell gas-water separator 3 provided in the present application further includes the following additional technical features: a gas-water separator 3, a PTC heating sheet 4, and a hydrogen concentration sensor 5 are arranged on the branch first inlet pipeline.

[0047] Specifically, the branch first inlet pipeline 21:

[0048] Gas-water separator 3

[0049] Definition: The gas-water separator 3 is a device used to remove water from gas.

[0050] Location: Located on the branch first inlet pipeline 21.

[0051] Function: Remove liquid water from the tail exhaust gas by physical methods such as cooling, gravity separation, etc., to reduce the humidity of the gas.

[0052] Structure:

[0053] Gas-water separator cavity 37: A cylindrical cavity with baffles 39 inside, which are arranged alternately to increase the gas path and promote the condensation and separation of water droplets.

[0054] Cooling water channel 38: Distributed in a spiral structure inside the outer wall 36 of the gas-water separator, the inlet and outlet of the cooling water channel 38 are opposite to the gas inlet 31 and the gas outlet 32 of the gas-water separator 3, in order to increase the heat exchange efficiency.

[0055] Baffle 39: Interleaved up and down in the cavity 37 of the gas-water separator, increasing the gas flow path, helping to condense and separate water.

[0056] Baffle drain hole 40: Located at the connection between the baffle 39 and the cavity bottom surface 41, used to collect liquid water flowing along the baffle 39 to the drain 33.

[0057] Cavity bottom surface 41: Inclined (1°~2°), helps to collect liquid water to the drain 33.

[0058] PTC heating sheet 4

[0059] Definition: PTC heating sheet 4 is a positive temperature coefficient heating element.

[0060] Position: Located behind the gas-water separator 3 and wrapped around the tail exhaust branch 2.

[0061] Function: Heating the gas after passing through the gas-water separator 3 to increase the gas temperature and reduce the relative humidity, preventing dew condensation on the surface of the hydrogen concentration sensor 5.

[0062] Heating temperature: The gas temperature is raised to 70~85℃.

[0063] Hydrogen concentration sensor 5

[0064] Definition: Hydrogen concentration sensor 5 is a sensor for measuring the concentration of hydrogen in the gas.

[0065] Position: Set at the corner of the tail exhaust branch 2.

[0066] Function: Measure the hydrogen concentration in the tail exhaust gas.

[0067] Advantages: On the one hand, located at the corner can directly receive the impact of the tail exhaust branch 2 gas, helping the gas to diffuse into the sensor and improve the measurement accuracy; on the other hand, if there is still liquid water, it can flow into the tail exhaust main pipeline 1 along the longitudinal section of the tail exhaust branch 2, reducing the impact on the sensor.

[0068] Work flow:

[0069] The tail exhaust gas first enters the gas-water separator 3, cools down by the cooling water and increases the gas path by the baffle 39 structure, reducing the gas temperature and humidity.

[0070] The separated gas is heated by the PTC heating sheet 4, further reducing the relative humidity of the gas.

[0071] The heated gas enters the hydrogen concentration sensor 5 for hydrogen concentration detection.

[0072] The cooling water is used to reduce the temperature of the gas-water separator 3, and the heat exchange efficiency is increased by the design of the cooling water flow channel 38.

[0073] The gas is heated by the PTC heating sheet 4 to ensure that the gas temperature is appropriate and to reduce the condensation phenomenon on the surface of the hydrogen concentration sensor 5.

[0074] The hydrogen concentration sensor 5 is placed at the corner, which is conducive to gas diffusion and improves the accuracy and precision of measurement.

[0075] Through this design, the humidity of the gas entering the hydrogen concentration sensor 5 can be effectively controlled, and the detection accuracy and service life of the sensor are improved.

[0076] According to one embodiment of the present application, the gas-water separator 3 includes a gas-water separator cavity 37, a gas-water separator outer wall 36, and a cooling water flow channel 38; the gas-water separator cavity 37 is a cylindrical cavity, the cooling water flow channel 38 is arranged around the gas-water separator cavity 37, and the outer side of the cooling water flow channel 38 is the gas-water separator outer wall 36.

[0077] Specifically, the gas-water separator 3 is an important component for separating water from the tail gas to reduce the humidity of the gas, thereby ensuring the accuracy of the hydrogen concentration sensor 5 and prolonging its service life. The gas-water separator 3 mainly includes the following parts:

[0078] Gas-water separator cavity 37

[0079] Shape: cylindrical cavity, such a design helps liquid water to gather at the bottom under the action of gravity.

[0080] Internal structure: baffles 39 are arranged inside the cavity, which are staggered to increase the flow path of the gas and help the condensation and separation of water.

[0081] Cavity bottom surface 41: designed to be slightly inclined (1°~2°), which helps liquid water to automatically flow to the drain 33.

[0082] Cooling water flow channel 38

[0083] Shape: circular cross-section, spiral structure uniformly distributed inside the gas-water separator outer wall 36.

[0084] Function: reduce the temperature of the gas-water separator 3 by cooling water, thereby reducing the saturated vapor pressure of the gas and reducing the water content in the gas.

[0085] Cooling water flow direction: The flow direction of the cooling water is opposite to that of the exhaust gas, which increases the heat exchange efficiency and reduces the gas temperature.

[0086] Gas-water separator outer wall 36

[0087] Location: Located outside the cooling water flow path 38.

[0088] Material: Typically made of metal to facilitate heat transfer.

[0089] Working principle

[0090] When the exhaust gas passes through the gas-water separator cavity 37, the liquid water in the gas will condense with the help of the baffle 39 and flow down along the baffle 39 and the inner wall, and finally converge to the drain outlet 33 through the baffle drain hole 40.

[0091] The cooling water in the cooling water flow path 38 flows in the opposite direction to the gas flow, which helps to improve the heat exchange efficiency, reduce the gas temperature, and reduce the water content in the gas.

[0092] After cooling, the temperature of the gas is reduced to 25-35°C, thereby reducing the saturated vapor pressure of the gas and further reducing the humidity of the gas.

[0093] Overall design advantages

[0094] Improved separation efficiency: By increasing the flow path of the gas and the contact time with the baffle 39, the cooling effect and water removal effect are enhanced.

[0095] Optimized heat exchange: The special design of the cooling water flow path 38 allows the gas temperature to be effectively reduced, reducing the humidity of the gas.

[0096] Convenient maintenance: The inclined cavity bottom surface 41 and the baffle drain hole 40 design facilitate automatic drainage of liquid water, reducing maintenance difficulty.

[0097] According to one embodiment of the present application, the gas-water separator cavity 37 includes a gas inlet 31, a gas outlet 32, a cavity bottom, and a baffle 39; the cavity bottom is provided with a baffle 39 drain outlet 33, and the cavity bottom is inclined at an angle of 1°-2°; the baffle 39 is arranged in the gas-water separator cavity 37 in an up-and-down staggered manner.

[0098] Specifically, the gas-water separator cavity 37 includes:

[0099] Gas inlet 31

[0100] Definition: The inlet of the gas-water separator 3 through which the gas enters.

[0101] Function: Directs the exhaust gas into the gas-water separator 3 for processing.

[0102] Gas outlet 32

[0103] Definition: The exit of the treated gas from the gas-water separator 3.

[0104] Function: To send the dry gas treated by the gas-water separator 3 to the next stage of processing or directly to the exhaust.

[0105] Cavity bottom

[0106] Definition: The lowest end of the gas-water separator cavity 37.

[0107] Features: It is inclined, with an inclination angle of about 1°-2°.

[0108] Function: To facilitate the collection of liquid water along the inclined surface to the drain 33, reducing the accumulation of liquid water at the bottom of the cavity.

[0109] Baffle 39

[0110] Definition: A partition set inside the gas-water separator cavity 37.

[0111] Layout: Interleaved vertically.

[0112] Function: To increase the gas flow path, making the gas stay longer in the gas-water separator 3, which is conducive to the condensation and separation of liquid water.

[0113] Structure: The baffle 39 is connected to the cavity bottom surface 41, and the baffle drain hole 40 is provided.

[0114] Baffle drain hole 40

[0115] Definition: A small hole located at the connection between the baffle 39 and the cavity bottom surface 41.

[0116] Function: To allow liquid water flowing down the baffle 39 and the inner wall to pass through these holes and gather in the drain 33 (33).

[0117] Overall function

[0118] Gas-water separation: Through the interleaved arrangement of the baffle 39 and the gravity of the liquid water, the liquid water in the gas condenses on the baffle 39 and the inner wall of the gas-water separator 3 and flows down along the baffle 39 and the inner wall.

[0119] Liquid discharge: Liquid water is collected to the bottom through the baffle drain hole 40, and flows to the drain 33 through the inclined cavity bottom surface 41 and is discharged.

[0120] Working principle

[0121] Gas entry: The exhaust gas enters the gas-water separator cavity 37 through the gas inlet 31.

[0122] Gas flow: The gas flows through the gas-water separator cavity 37 and interacts with the staggered baffles 39.

[0123] Liquid water separation: The liquid water in the gas condenses on the baffles 39 and the inner wall and flows down the baffles 39 and the inner wall.

[0124] Liquid collection: The liquid water collects at the bottom through the baffle drain holes 40.

[0125] Liquid discharge: The liquid water flows to the drain 33 along the inclined cavity bottom surface 41 and is discharged.

[0126] Advantages

[0127] High-efficiency separation: By increasing the gas flow path and the contact time with the baffles 39, the cooling effect is enhanced, and the separation efficiency of the liquid water is improved.

[0128] Avoiding liquid accumulation: The design of the inclined cavity bottom surface 41 and the baffle drain holes 40 helps to avoid the accumulation of liquid water in the gas-water separator 3.

[0129] Easy maintenance: The simple structure design makes daily maintenance and cleaning simple and fast.

[0130] According to one embodiment of the present application, the cooling water flow channel 38 is circular in cross-section, and the cooling water flow channel 38 is arranged in a spiral structure in the outer wall of the gas-water separator.

[0131] Specifically, the design of the cooling water flow channel 38

[0132] Cross-sectional shape: The cooling water flow channel 38 is circular in cross-section.

[0133] Layout structure: The cooling water flow channel 38 is arranged in a spiral structure in the outer wall 36 of the gas-water separator.

[0134] Function of the cooling water flow channel 38

[0135] Cooling purpose: The main purpose of the cooling water flow channel 38 is to reduce the temperature of the gas-water separator 3 by water cooling, thereby reducing the temperature and humidity of the exhaust gas.

[0136] Heat exchange efficiency: The design of the cooling water flow channel 38 makes the overall forward direction of the cooling water opposite to the overall flow direction of the exhaust gas, which can increase the heat exchange efficiency and effectively reduce the gas temperature.

[0137] Working principle of the cooling water flow channel 38

[0138] Cooling water flow: The cooling water enters from the cooling water inlet 34, then flows along the spiral cooling water flow channel 38, and finally is discharged from the cooling water outlet 35.

[0139] Heat exchange process: Due to the spiral structure of the cooling water channel 38, the contact area between the cooling water and the outer wall of the gas-water separator 36 increases, improving the heat exchange efficiency. The inlet and outlet of the cooling water channel 38 are arranged opposite to the gas inlet 31 and gas outlet 32 of the gas-water separator 3, which means that the flow direction of the cooling water is opposite to that of the gas, which helps to further improve the heat exchange efficiency.

[0140] Cooling effect: The cooling water in the cooling water channel 38 can significantly reduce the temperature of the gas flowing through the gas-water separator 3, reducing the temperature of the gas discharged from the gas-water separator 3 to 25-35℃, thereby reducing the gas saturated vapor pressure and reducing the water content in the gas.

[0141] Design advantages of the cooling water channel 38

[0142] Increase heat exchange efficiency: The spiral structure and opposite flow direction of the cooling water channel 38 can effectively increase the heat exchange area and efficiency, thereby more effectively reducing the gas temperature.

[0143] Reduce gas humidity: By reducing the temperature of the gas, the water content in the gas can be reduced, and the humidity of the gas can be reduced, which is very important for the subsequent hydrogen concentration sensor 5 detection, because lower humidity can avoid the condensation of liquid water on the sensor surface, improve detection accuracy and prolong the service life of the sensor.

[0144] Optimized structure: The circular cross-section of the cooling water channel 38 design can reduce fluid resistance and ensure smooth flow of cooling water, while the spiral structure helps to evenly distribute the cooling effect.

[0145] According to one embodiment of the present application, the inlet and outlet of the cooling water channel 38 are arranged opposite to the gas inlet 31 and gas outlet 32, so that the overall forward direction of the cooling water in the cooling water channel 38 is opposite to the overall flow direction of the exhaust gas in the branch first gas inlet pipe.

[0146] Design of the cooling water channel 38

[0147] Position of the inlet and outlet: The inlet and outlet of the cooling water channel 38 are designed to be in the opposite direction of the gas inlet 31 and gas outlet 32 of the gas-water separator 3.

[0148] Cooling water flow direction: After the cooling water enters the cooling water channel 38 from the inlet, its flow direction is opposite to that of the exhaust gas in the branch first gas inlet pipe.

[0149] Design purpose

[0150] Increase heat exchange efficiency: By making the flow direction of the cooling water opposite to that of the gas, the efficiency of heat exchange can be increased. This is because when the gas and the cooling water flow in opposite directions, the temperature difference between them is greater, thereby improving the heat exchange efficiency.

[0151] Lowering the gas temperature: In this way, the cooling water can more effectively absorb the heat in the gas, lower the temperature of the gas, and in turn lower the saturated vapor pressure of the gas, reducing the water content in the gas.

Claims

1. A device for testing the concentration of tail hydrogen of a fuel cell gas water separator, characterized by, The exhaust branch includes a first branch intake pipeline and a second branch intake pipeline, and the first branch intake pipeline and the second branch intake pipeline are connected with the exhaust main pipeline; a gas circulating pump is arranged on the first branch intake pipeline, and the gas inlet of the second branch intake pipeline has a larger gas inlet cross section than the pipeline gas flow cross section of the second branch intake pipeline; the outlet of the exhaust branch is connected with the exhaust main pipeline, and a Venturi structure is arranged at the connection.

2. The apparatus of claim 1, wherein, A gas-water separator, a PTC heating sheet and a hydrogen concentration sensor are arranged on the first branch intake pipeline, and the hydrogen concentration sensor is arranged at a corner of the exhaust branch.

3. The apparatus of claim 2, wherein, The gas-water separator includes a gas-water separator cavity, a gas-water separator outer wall and a cooling water flow channel; the gas-water separator cavity is a cylindrical cavity, the cooling water flow channel is arranged around the gas-water separator cavity, and the outer side of the cooling water flow channel is the gas-water separator outer wall.

4. The apparatus of claim 3, wherein, The gas-water separator cavity includes a gas inlet, a gas outlet, a cavity bottom and a baffle; the cavity bottom is provided with a baffle drain port, and the cavity bottom is arranged obliquely at an angle of 1° to 2°; the baffles are arranged in the gas-water separator cavity in an up-and-down staggered manner.

5. The apparatus of claim 3, wherein, The cross section of the cooling water flow channel is circular, and the cooling water flow channel is arranged in a spiral structure in the gas-water separator outer wall.

6. The apparatus of claim 5, wherein, The inlet and outlet of the cooling water flow channel are arranged opposite to the gas inlet and the gas outlet, so that the overall advancing direction of the cooling water in the cooling water flow channel is opposite to the overall flow direction of the exhaust gas in the first branch intake pipeline.

7. The apparatus of claim 1, wherein, The gas circulating pump is used for gas extraction, and the gas circulating pump includes but is not limited to a vortex type, a Roots type and a centrifugal type.

8. The apparatus of claim 2, wherein, The PTC heating sheet is arranged in front of the hydrogen concentration sensor and is used for heating gas, improving gas temperature and reducing gas humidity.

9. The apparatus of claim 8, wherein, The PTC heating sheet is wrapped on the exhaust branch.

10. The apparatus of claim 9, wherein, The gas-water separator is arranged in front of the PTC heating sheet and is used for reducing the temperature of the exhaust mixed gas passing through.

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