CN216120379U

CN216120379U - Ejector and fuel cell system comprising same

Info

Publication number: CN216120379U
Application number: CN202121544529.1U
Authority: CN
Inventors: 于鑫淼; 林业发; 王志斌; 李然; 尹志伟
Original assignee: Shanghai Electric Group Corp
Current assignee: Shanghai Electric Group Corp
Priority date: 2021-07-07
Filing date: 2021-07-07
Publication date: 2022-03-22
Anticipated expiration: 2031-07-07

Abstract

The utility model discloses an ejector and a fuel cell system comprising the same, wherein the ejector is used in the fuel cell system and comprises a shell, a first cavity and a second cavity which are mutually separated are arranged in the shell, a backflow gas inlet for backflow gas to enter and a gas outlet for mixed gas to flow out are arranged on the shell, the backflow gas inlet is communicated with the first cavity, the gas outlet is communicated with the second cavity, the ejector further comprises a plurality of ejector components, all the ejector components are arranged in the shell, the ejector components are used for ejecting the backflow gas in the first cavity, and one end of each ejector component extends into the second cavity and is communicated with the second cavity. Set up a plurality of subassemblies that draw in the casing to increase whole ejector draw gaseous flow and pressure, also increased backflow gas's reflux ratio simultaneously, and then the increase draws the gaseous mixed gas's of penetrating gas and backflow gas flow. Moreover, the length of a single ejector assembly can be reduced, and the volume of the ejector can be further reduced.

Description

Ejector and fuel cell system comprising same

Technical Field

The utility model relates to the field of fuel cells, in particular to an ejector and a fuel cell system comprising the ejector.

Background

At present, due to the fact that hydrogen fuel cell automobiles develop in the future, most hydrogen fuel cell systems are still the traditional single spray pipe ejector which only comprises one ejector pipe and one nozzle, and the single spray pipe ejector cannot meet the requirements of a novel fuel cell system from gas flow, ejector reflux ratio or ejector volume. This is because the gas flow into a nozzle is limited and the pressure in a nozzle is also limited. In order to satisfy the injection condition, even if the caliber of the outlet of the nozzle is reduced to increase the rate of the injection gas, compared with the fuel cell system, only one nozzle is adopted, the flow and the pressure of the injection gas are still limited, the backflow gas injected by the injection gas is also limited, the flow rate of the mixed gas obtained by mixing the injection gas and the backflow gas is also limited, and the requirements of the fuel cell system on the flow and the flow rate of the fuel gas cannot be met.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defect that the gas flow of an ejector in the prior art is limited, and provides the ejector and a fuel cell system comprising the same.

The utility model solves the technical problems through the following technical scheme:

an ejector is used in a fuel cell system and comprises a shell, a first cavity and a second cavity which are mutually separated are arranged in the shell, a backflow gas inlet for backflow gas to enter and a gas outlet for mixed gas to flow out are arranged on the shell, the backflow gas inlet is communicated with the first cavity, the gas outlet is communicated with the second cavity, and the ejector is characterized in that,

the ejector further comprises a plurality of ejection assemblies, the ejection assemblies are arranged in the shell and used for ejecting the backflow gas in the first cavity, and one end of each ejection assembly extends into the second cavity and is communicated with the second cavity.

In the scheme, the ejector assembly sucks backflow gas into the ejector assembly through supersonic ejector gas, mixes the backflow gas with the ejector gas and then flows out from an outlet of the ejector assembly. Set up a plurality of subassemblies that draw in the casing to increase whole ejector draw gaseous flow and pressure, also increased backflow gas's reflux ratio simultaneously, and then the increase draws the gaseous mixed gas's of penetrating gas and backflow gas flow. The outlet ends of the plurality of injection assemblies extend into the second cavity, so that mixed gas flowing out of the injection assemblies converges in the second cavity and then flows out of the gas outlet of the shell. This results in a higher flow rate and a higher pressure of the mixed gas flowing out of the gas outlet. Moreover, the length of a single ejector assembly can be reduced, and the volume of the ejector can be further reduced.

Preferably, the injection assembly comprises a nozzle for accelerating injection gas and an injection pipe for mixing backflow gas and injection gas, the shell is provided with a gas inlet, an inlet of the nozzle is communicated with the gas inlet, and one end of the nozzle, which deviates from the inlet of the nozzle, extends into the injection pipe. The injection gas is pressurized by the nozzle and then flows into the injection pipe from the outlet of the nozzle at supersonic speed, and at the moment, a negative pressure area is formed in the injection pipe so as to adsorb the backflow gas into the injection pipe. The inlet of the nozzle is connected to the gas inlet on the housing such that the injection gas under pressure flows from the gas inlet into the nozzle. Deviating from the one end of nozzle entry on the nozzle, the exit end that also is the nozzle stretches into to draw in penetrating intraductally for draw after the nozzle is accelerated and penetrate inside of penetrating the pipe more accurately, be favorable to improving the ability of drawing penetrating the subassembly.

Preferably, the injection pipe comprises an intake section, a mixing section and a diffusion section which are sequentially communicated, the injection pipe is further provided with an injection port, the injection port is formed in the side wall corresponding to the intake section, and the injection port is communicated with the first cavity. The first chamber is communicated with the inlet of the backflow gas, namely, the backflow gas enters the first chamber from the inlet of the backflow gas. And the injection port is communicated with the first cavity, so that the injection port of the backflow gas in the first cavity enters the injection pipe.

Preferably, the inner diameter of the suction section decreases gradually from the end facing away from the mixing section to the end facing the mixing section;

the inner diameter of the mixing section is constant;

the inner diameter of the diffusion section gradually increases from one end facing the mixing section to one end away from the mixing section.

In this scheme, after the section of inhaling that the ejection was jetted into and is jetted the pipe from the ejecting gaseous injection of spout in the nozzle, owing to inhale the internal diameter of section by diminishing greatly, further accelerated the velocity of flow that jets gas for the pressure at the great position of internal diameter of the section of inhaling is less than the pressure at the less position of internal diameter, also makes to produce pressure differential in the department of injecting mouthful, and then makes the backflow gas in the first cavity inhale and draw in the pipe. The mixing section is used for mixing the injection gas and the backflow gas. The internal diameter of diffuser is by little grow to reduce the gaseous pressure after mixing, and then reduce the velocity of flow of mist, so that the velocity of flow of mist can adapt to fuel cell system to fuel gas's demand, and then make fuel gas ability fully participate in the reaction, with the utilization ratio that improves fuel gas.

Preferably, the end of the nozzle extends beyond the ejection port and towards the mouth of the mixing section. By adopting the arrangement, the injection gas flowing out from the nozzle can completely flow into the injection pipe and can not flow out from the injection port, and the injection capacity and the gas utilization rate of the injection assembly can be improved.

Preferably, the injection port on the injection pipe faces the inner wall of the shell. By adopting the arrangement, the ejection ports on the plurality of ejection pipes cannot be mutually influenced, and the reflux ratio of the backflow gas can be improved.

Preferably, the number of the injection assemblies is three. The three injection components are adopted, so that the flow speed and flow of injection gas of the injector can be improved, the reflux ratio of reflux gas is also improved, and the gas utilization rate is further improved. Meanwhile, the length of a single ejector pipe is reduced, and the volume of the whole ejector can be reduced.

Preferably, the housing includes a cylindrical housing with openings at two ends, a first end cap and a second end cap, the first end cap and the second end cap are detachably connected to two ends of the cylindrical housing, the gas inlet is disposed on the first end cap, and the gas outlet is disposed on the second end cap. The injection assembly is convenient to mount by adopting the arrangement mode.

Preferably, the ejector further comprises a mounting base, the mounting base is connected to the first end cover, an air inlet cavity is defined between the mounting base and the first end cover, and an inlet of the nozzle is communicated with the air inlet cavity. An air inlet cavity is defined between the mounting base and the first end cover, so that high-pressure air flowing in from the air inlet firstly flows into the air inlet cavity; and the inlet of the nozzle is communicated with the air inlet cavity, so that high-pressure air entering the air inlet cavity enters the nozzle through the inlet of the nozzle. By adopting the arrangement, the air inlet and the plurality of nozzles are conveniently communicated, and the arrangement of the plurality of injection assemblies is facilitated, so that the structure of the injector is simplified.

Preferably, the installation base is provided with a first through hole corresponding to the injection pipe, the injection pipe is connected to one side of the installation base, and one end of the nozzle penetrates through the first through hole and extends into the injection pipe. Through above structural style for it is a whole to be connected between a plurality of injection subassemblies and the installation base, and then improves a plurality of integrated properties of injecting the subassembly, thereby is convenient for the installation of whole ejector.

Preferably, the shell further comprises a baffle, the baffle is integrally arranged with the cylindrical shell, or the baffle is detachably connected with the cylindrical shell;

the second end cover and the baffle plate enclose the second cavity.

The second cavity is enclosed between the second end cover and the baffle plate, so that the first cavity and the second cavity are mutually independent, backflow gas in the first cavity is prevented from entering the second cavity, and uniformity of gas in the second cavity is influenced.

Preferably, the baffle is provided with a second through hole corresponding to the injection pipe, and one end of the injection pipe, which is back to the nozzle, penetrates through the second through hole and extends into the second cavity. The end of the injection pipe, which is far away from the nozzle, namely the outlet end of the injection pipe, penetrates through the second through hole in the baffle plate and then extends into the second cavity, so that the gas mixed by the injection pipe is converged in the second cavity and then flows out from the gas outlet.

A fuel cell system characterised by comprising an ejector as described above.

In the scheme, the ejector with the structure is adopted, so that the flow speed and flow of hydrogen are improved, the hydrogen reflux ratio is improved, and the utilization rate of the hydrogen is improved; and the volume of the ejector can be reduced, so that the volume of the fuel cell system is reduced, and the space is saved.

On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the utility model.

The positive progress effects of the utility model are as follows: according to the ejector, the plurality of ejector components are arranged in the shell, so that the flow and the pressure of the ejector gas of the whole ejector are increased, the reflux ratio of the backflow gas is increased, and the flow of the mixed gas of the ejector gas and the backflow gas is increased. The outlet ends of the plurality of injection assemblies extend into the second cavity, so that mixed gas flowing out of the injection assemblies converges in the second cavity and then flows out of the gas outlet of the shell. This results in a higher flow rate and a higher pressure of the mixed gas flowing out of the gas outlet. Moreover, the length of a single ejector assembly can be reduced, and the volume of the ejector can be further reduced.

Drawings

Fig. 1 is a schematic external structural view of an ejector according to a preferred embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view of an ejector according to a preferred embodiment of the present invention.

Fig. 3 is a schematic structural view of the ejector assembly of the ejector according to the preferred embodiment of the present invention after being mounted on the mounting base.

Fig. 4 is a schematic structural diagram of a cylindrical housing in a housing of an ejector according to a preferred embodiment of the present invention.

Fig. 5 is a schematic structural view of a nozzle in an ejector assembly in an ejector according to a preferred embodiment of the present invention.

Fig. 6 is a schematic structural view of a second end cap in a housing of an eductor in accordance with a preferred embodiment of the present invention.

Fig. 7 is a schematic structural view of a first end cap in a housing of an eductor in accordance with a preferred embodiment of the present invention.

Description of reference numerals:

housing 10

Cylindrical case 101

Return gas inlet 1011

Baffle 1012

Second through hole 1012a

First end cap 102

Gas inlet 1021

Second end cap 103

Air outlet 1031

First chamber 104

Second cavity 105

Air inlet cavity 106

Ejector assembly 20

Injection pipe 201

Suction segment 2011

Mixing stage 2012

Diffuser segment 2013

Injection port 2011a

Nozzle 202

Inlet 2021 of nozzle

Outlet 2022 of nozzle

Step 2023

Annular groove 2023a

Mounting base 30

Detailed Description

The present invention will be more clearly and completely described below by way of examples and with reference to the accompanying drawings, but the present invention is not limited thereto.

As shown in fig. 1 to 7, the present embodiment provides an ejector, which is used in a fuel cell system, and the present embodiment is described by taking a hydrogen fuel cell as an example. The ejector comprises a shell 10, wherein a first cavity 104 and a second cavity 105 which are mutually spaced are arranged in the shell 10, a backflow gas inlet 1011 for backflow gas, namely backflow hydrogen gas, to enter is arranged on the shell 10, and the backflow hydrogen gas inlet is suitable for being connected with a gas-liquid separation device in a hydrogen fuel cell system. After the unreacted hydrogen gas is subjected to gas-liquid separation by the gas-liquid separation device, the unreacted hydrogen gas enters the first cavity 104 from the return gas inlet 1011. The housing 10 is further provided with a gas outlet 1031 for mixed gas to flow out, wherein the mixed gas is the mixed gas of hydrogen from the hydrogen supply device and backflow hydrogen for injecting backflow hydrogen. In order to make the backflow hydrogen gas smoothly enter the first chamber 104, the backflow gas inlet 1011 is communicated with the first chamber 104, and the gas outlet 1031 on the housing 10 is communicated with the second chamber 105, so that the mixed gas entering the second chamber 105 is discharged from the gas outlet 1031. The ejector further comprises a plurality of ejector assemblies 20, all the ejector assemblies 20 are arranged in the shell 10, the ejector assemblies 20 are used for ejecting backflow gas in the first cavity 104, and one ends of the ejector assemblies 20 extend into the second cavity 105 and are communicated with the second cavity 105.

The ejector assembly 20 sucks the backflow gas into the ejector assembly 20 through supersonic ejector gas, mixes the backflow gas with the ejector gas, and then flows out from an outlet of the ejector assembly 20. Set up a plurality of injection subassemblies 20 in casing 10 to increase the gaseous flow and the pressure of drawing of whole ejector, also increased backflow gas's reflux ratio simultaneously, and then increase the gaseous mixed gas's of drawing injection and backflow flow. The outlet ends of the plurality of ejector assemblies 20 extend into the second chamber 105, so that the mixed gas flowing out of the ejector assemblies 20 converges in the second chamber 105 and then flows out of the gas outlet 1031 on the housing 10. This allows the mixed gas to flow out of the gas outlet 1031 at a higher flow rate and a higher pressure. Moreover, the length of a single ejector assembly 20 can be reduced, and the volume of the ejector can be further reduced.

In this embodiment, the eductor assembly 20 includes a nozzle 202 for accelerating the eductor gas and an eductor tube 201 for mixing the return gas and the eductor gas. The casing 10 is provided with a gas inlet 1021, an inlet 2021 of the nozzle is communicated with the gas inlet 1021, and one end of the nozzle 202, which is far away from the inlet 2021 of the nozzle, extends into the injection pipe 201. A flow channel is disposed along the axial direction of the nozzle 202, and the flow channel penetrates from one end of the nozzle 202 to the other end, and one end of the flow channel is connected to the gas inlet 1021, i.e. the inlet 2021 of the nozzle is as described above, and the other end of the flow channel surrounds the outlet 2022 of the nozzle. The inner diameter of the flow channel is constant from one end of the inlet, then gradually decreases, and then gradually increases. The position where the inner diameter of the flow channel is smallest is the pressurizing port of the nozzle. The injection gas is pressurized through the pressurizing port of the nozzle and then flows into the injection pipe 201 from the outlet 2022 of the nozzle at supersonic speed, and at this time, a negative pressure region is formed in the injection pipe 201 to adsorb the backflow gas into the injection pipe 201. The nozzle inlet 2021 is connected to the gas inlet 1021 of the housing 10 such that a pressurized injection gas flows from the gas inlet 1021 into the nozzle 202. One end deviating from the nozzle inlet on the nozzle 202, that is, the outlet 2022 end of the nozzle extends into the injection pipe 201, so that the injection gas accelerated by the nozzle 202 is more accurately injected into the injection pipe 201, and the injection capability of the injection assembly 20 is favorably improved.

The injection pipe 201 comprises a suction section 2011, a mixing section 2012 and a diffusion section 2013 which are sequentially communicated, wherein the inner diameter of the suction section 2011 is gradually reduced from one end, away from the mixing section 2012, to one end, facing the mixing section 2012; the inner diameter of the mixing section 2012 is constant; the inner diameter of the diverging section 2013 increases from the end toward the mixing section 2012 to the end away from the mixing section 2012. The injection pipe 201 is further provided with an injection port 2011a, the injection port 2011a is formed in the side wall corresponding to the suction section 2011, and the injection port 2011a is communicated with the first cavity 104. The first chamber 104 is connected to the inlet of the return gas, i.e. the return gas enters the first chamber 104 from the inlet of the return gas. The injection port 2011a is communicated with the first cavity 104, so that the injection port 2011a of the backflow gas in the first cavity 104 enters the injection pipe 201. After the injection gas ejected from the nozzle 202 is ejected into the suction section 2011 of the injection pipe 201, the inner diameter of the suction section 2011 is reduced, so that the flow rate of the hydrogen flowing into the injection pipe 201 from the hydrogen supply device is further increased, the pressure of the part with the large inner diameter of the suction section 2011 is smaller than the pressure of the part with the small inner diameter, namely the pressure difference is generated at the injection port 2011a, and then the backflow hydrogen in the first cavity 104 is sucked into the injection pipe 201. The mixing section 2012 is used to mix the ejector gas and the return gas. The internal diameter of diffuser 2013 is by little grow to reduce the gaseous pressure after the mixture, and then reduce the velocity of flow of mist, so that the velocity of flow of mist can adapt to fuel cell system to fuel gas's demand, and then make the fuel gas fully participate in the reaction, with the utilization ratio that improves fuel gas.

Further, the end of the nozzle 202 extends beyond the injection port 2011a and towards the mouth of the mixing section 2012. With the adoption of the arrangement, all the injection gas flowing out from the nozzle 202 flows into the injection pipe 201 and does not flow out from the injection port 2011a, so that the injection capacity and the gas utilization rate of the injection assembly 20 can be improved. In this embodiment, three injection assemblies 20 are arranged in one housing 10, and three injection assemblies 20 are adopted, so that the flow rate and the flow rate of injection gas of the injector can be improved, the reflux ratio of reflux gas is also improved, and the gas utilization rate is further improved. Meanwhile, the length of a single ejector pipe 201 is reduced, and the volume of the whole ejector can be reduced. The injection port 2011a of each injection pipe 201 is opposite to the inner wall of the casing 10. By adopting the arrangement, the injection ports 2011a on the plurality of injection pipes 201 cannot be mutually influenced, and the reflux ratio of the reflux gas can be further improved.

In this embodiment, the housing 10 includes a cylindrical housing with two open ends, a first end cap 102 and a second end cap 103, the first end cap 102 and the second end cap 103 are detachably connected to two ends of the cylindrical housing, the gas inlet 1021 is disposed on the first end cap 102, and the gas outlet 1031 is disposed on the second end cap 103. This arrangement facilitates installation of the injection assembly 20. The detachable connection manner of the first end cap 102 and the second end cap 103 with the cylindrical housing 101 is not limited, and in this embodiment, the first end cap 102 and the second end cap 103 are detachably connected with the cylindrical housing 101 through flanges.

Further, the ejector further comprises a mounting base 30, wherein the mounting base 30 is a boss with one side being a plane and the other side being partially protruded outwards. The first end cover 102 has a cavity therein, the mounting base 30 is connected to the first end cover 102, an air inlet chamber 106 is defined between the mounting base 30 and the first end cover 102, and the air inlet is disposed at an end of the first end cover 102 facing away from the mounting base 30. The cross-sectional area of the inlet chamber 106 decreases from the mounting base 30 toward the outlet 1031. The inlet 2021 of the nozzle communicates with the inlet chamber 106. An air inlet cavity 106 is defined between the mounting base 30 and the first end cover 102, so that high-pressure air flowing in from the air inlet firstly flows into the air inlet cavity 106; and the nozzle inlet 2021 is in communication with the inlet chamber 106, such that high pressure gas entering the inlet chamber 106 enters the nozzle through the nozzle inlet 2021. With the arrangement, the air inlet and the plurality of nozzles 202 are conveniently communicated, so that the arrangement of the plurality of injection assemblies 20 is facilitated, and the structure of the injector is simplified.

In this embodiment, the installation base 30 is provided with a first through hole corresponding to the injection pipe 201, the injection pipe 201 is connected to one side of the installation base 30, and one end of the nozzle 202 penetrates through the first through hole and extends into the injection pipe 201. The end of the nozzle 202 facing the inlet has a step 2023, the size of the step 2023 is larger than the diameter of the first through hole, the side surface of the step 2023 is attached to the mounting base 30, and the step 2023 is used for limiting the nozzle 202. An annular groove 2023a is provided on the side surface of the step 2023 to which the mounting base 30 is attached, and a seal ring is provided in the annular groove 2023a to improve the sealing performance between the nozzle 202 and the mounting base 30 and prevent air leakage from the gap between the nozzle 202 and the mounting base 30. The injection pipe 201 and the mounting base 30 may be connected by a thread or may be fixed by welding. Through above structural style for it is a whole to be connected between a plurality of injection subassembly 20 and the installation base 30, and then improves a plurality of integrated properties of injecting subassembly 20, thereby is convenient for the installation of whole ejector.

In this embodiment, the housing 10 further includes a baffle 1012, the baffle 1012 is integrally provided with the cylindrical housing, or the baffle 1012 is detachably connected with the cylindrical housing; the second end cap 103 and the baffle 1012 enclose a second cavity 105.

The cross-sectional area of the second chamber 105 decreases from the baffle 1012 to the end of the outlet 1031. The second cavity 105 is enclosed between the second end cap 103 and the baffle 1012, so that the first cavity 104 and the second cavity 105 are independent from each other, thereby preventing backflow gas in the first cavity 104 from entering the second cavity 105 to affect uniformity of gas in the second cavity 105. The baffle 1012 is provided with a second through hole 1012a corresponding to the injection pipe 201, and one end of the injection pipe 201 departing from the nozzle 202 penetrates through the second through hole 1012a and extends into the second cavity 105. One end of the injection pipe 201 departing from the nozzle 202, that is, the outlet end of the injection pipe 201, penetrates the outlet end of the injection pipe 201 through the second through hole 1012a of the baffle 1012 and then extends into the second cavity 105, so that the gas mixed by the injection pipe 201 converges in the second cavity 105 and then flows out of the gas outlet 1031. An L-shaped fixing plate is provided on the mounting base 30 for connection with other structures in the fuel cell system.

The embodiment also provides a fuel cell system, which comprises the ejector. A return gas inlet 1011 on the ejector is communicated with an outlet of a gas-liquid separation device in the fuel cell system; and a gas inlet on the ejector is connected with an outlet of the hydrogen supply system. In the fuel cell system, the ejector with the structure is adopted, so that the flow speed and flow of hydrogen are improved, the hydrogen reflux ratio is also improved, and the utilization rate of the hydrogen is improved; and the volume of the ejector can be reduced, so that the volume of the fuel cell system is reduced, and the space is saved.

While specific embodiments of the utility model have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and that the scope of the utility model is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the utility model, and these changes and modifications are within the scope of the utility model.

Claims

1. An ejector is used in a fuel cell system and comprises a shell, a first cavity and a second cavity which are mutually separated are arranged in the shell, a backflow gas inlet for backflow gas to enter and a gas outlet for mixed gas to flow out are arranged on the shell, the backflow gas inlet is communicated with the first cavity, the gas outlet is communicated with the second cavity, and the ejector is characterized in that,

2. The eductor as defined in claim 1 wherein said eductor assembly includes a nozzle for accelerating the eductor gas and an eductor tube for mixing the return gas and the eductor gas, said housing having a gas inlet, an inlet of said nozzle communicating with said gas inlet, an end of said nozzle remote from said inlet of said nozzle extending into said eductor tube.

3. The ejector according to claim 2, wherein the ejector tube comprises an suction section, a mixing section and a diffusion section which are sequentially communicated, the ejector tube is further provided with an ejector port, the ejector port is formed in a side wall corresponding to the suction section, and the ejector port is communicated with the first cavity.

4. The injector of claim 3,

the inner diameter of the suction section is gradually reduced from one end departing from the mixing section to one end facing the mixing section;

the inner diameter of the mixing section is constant;

5. The eductor as defined in claim 3 wherein the end of said nozzle extends beyond said eductor port and toward the mouth of said mixing section.

6. The eductor according to claim 3 wherein the eductor port of said eductor tube is directed toward the interior wall of said housing.

7. The eductor as defined in any one of claims 1 to 6 wherein the number of eductor components is three.

8. The injector of claim 2,

the shell comprises a cylindrical shell with two open ends, a first end cover and a second end cover, wherein the first end cover and the second end cover are respectively detachably connected with the two ends of the cylindrical shell, a gas inlet is formed in the first end cover, and a gas outlet is formed in the second end cover.

9. The injector of claim 8, further comprising a mounting base coupled to the first end cap, the mounting base and the first end cap defining an air intake chamber therebetween, the inlet of the nozzle communicating with the air intake chamber.

10. The injector according to claim 9, wherein the mounting base is provided with a first through hole corresponding to the injection pipe, the injection pipe is connected to one side of the mounting base, and one end of the nozzle penetrates through the first through hole and extends into the injection pipe.

11. The injector of claim 9,

the shell also comprises a baffle, and the baffle and the cylindrical shell are integrally arranged, or the baffle and the cylindrical shell are detachably connected;

the second end cover and the baffle plate enclose the second cavity.

12. The injector of claim 11, wherein the baffle is provided with a second through hole corresponding to the injection pipe, and one end of the injection pipe, which is away from the nozzle, penetrates through the second through hole and extends into the second cavity.

13. A fuel cell system comprising the ejector according to any one of claims 1 to 12.