Compressor interstage diffusion flow guide structure, compressor and fuel cell system

Abstract

The utility model discloses a compressor interstage diffusion flow guide structure, a compressor and a fuel cell system, and the compressor interstage diffusion flow guide structure comprises a compressor body which is internally provided with an interstage axial airflow channel; the first-stage compression assembly is arranged at one end of the compressor body, the first-stage compression assembly comprises a first-stage impeller and a first-stage volute, the first-stage volute is connected with the compressor body, the first-stage impeller is arranged in the first-stage volute, and the second-stage impeller is arranged in the second-stage volute; a diffusion fluid director is arranged between an outlet of the first-stage impeller and the inter-stage axial airflow channel, the diffusion fluid director is provided with a plurality of fluid director rib plates, and diffusion flow channels are formed between the adjacent fluid director rib plates of the diffusion fluid director. The flow guide rib plates obliquely extend in the outlet airflow direction of the first-stage impeller at the inlet of the diffusion flow channel, and the flow guide rib plates extend in a transition mode in the radial direction of the diffusion flow guider at the outlet of the diffusion flow channel. According to the utility model, the airflow energy loss of airflow redirection can be greatly reduced.

Description

TECHNICAL FIELD

[0001] The utility model is used in the field of air compressor, especially relates to a compressor interstage diffuser guide vane structure, compressor and fuel cell system. BACKGROUND

[0002] It is the consensus of the international community to replace traditional energy with clean energy, reduce carbon dioxide emissions worldwide, and thus alleviate environmental pollution. Hydrogen energy has the advantages of high heat value, zero carbon and pollutant emissions, and wide distribution, and is one of the most promising clean energy in the context of "carbon reduction".

[0003] Fuel cells are devices that convert hydrogen energy into electrical energy through electrochemical reactions. Because they are not limited by the Carnot cycle, they have very high energy conversion efficiency and are key equipment that connects the upstream energy end and the downstream application end of the hydrogen energy industry chain. Realizing large-scale commercialization and industrialization of fuel cells is of great significance to the in-depth promotion of energy transformation.

[0004] Proton exchange membrane fuel cells are a type of fuel cell that has the advantages of fast start-up speed, low operating temperature, high power density, and zero emissions, and represents the development trend of future automobile engines. In fuel cell engines, high-speed air-floating compressors provide high-pressure air with a certain flow rate and pressure for hydrogen-oxygen electrochemical reactions on the proton exchange membrane, ensuring that the fuel cell outputs corresponding electrical power.

[0005] Fuel cell air compressors are high-speed centrifugal gas compression equipment supported by foil gas dynamic bearings, with rotational speeds often reaching 100,000 rpm or even higher. They have the advantages of high speed, gas lubrication, complete oil-free, small size, and light weight, and are the core gas supply equipment for vehicle-mounted fuel cell engines.

[0006] Because fuel cell engines have a wide operating range, they require fuel cell air compressors to provide corresponding air flow and pressure changes in a wide range under conditions such as idle speed, full speed, different step speeds, and acceleration and deceleration. In order to meet the requirements of wide pressure ratio and wide flow range, fuel cell air compressors often use a two-stage compression method, i.e., high-pressure air passing through a primary compression impeller is then introduced into a secondary impeller for centrifugal acceleration.

[0007] High-pressure air passing through a primary compression impeller is usually introduced into a secondary impeller in two ways: outside the compressor body and inside the compressor body.

[0008] The gas flow from the first-stage impeller outlet is directly guided from the centrifugal outlet to the second-stage impeller inlet through a pipe, and the gas flow changes direction. The pipe has a large space for the change of the direction of the gas flow, and the energy loss of the gas flow caused by the change of the direction of the gas flow can be reduced. However, the space occupied by the pipe is large, the overall size of the compressor is large, and the volumetric power density of the fuel cell engine is reduced. In addition, the gas flow from the first stage to the second stage can only be naturally cooled through the pipe outside the compressor body, and the cooling efficiency is not high, which is not conducive to improving the compression efficiency of the second-stage impeller.

[0009] The gas flow from the first-stage impeller outlet is directly guided from the centrifugal outlet to the second-stage impeller inlet through a pipe, and the gas flow changes direction. The pipe has a large space for the change of the direction of the gas flow, and the energy loss of the gas flow caused by the change of the direction of the gas flow can be reduced. However, the space occupied by the pipe is large, the overall size of the compressor is large, and the volumetric power density of the fuel cell engine is reduced. In addition, the gas flow from the first stage to the second stage can only be naturally cooled through the pipe outside the compressor body, and the cooling efficiency is not high, which is not conducive to improving the compression efficiency of the second-stage impeller.

[0010] Therefore, the problems in the related art need to be solved. Content of the utility model

[0011] The utility model discloses a compressor interstage diffuser guide structure, compressor and fuel cell system, and at least one of the technical problems in the prior art is solved.

[0012] The utility model discloses a compressor interstage diffuser guide structure, compressor and fuel cell system, and at least one of the technical problems in the prior art is solved.

[0013] In a first aspect, a compressor interstage diffuser guide structure comprises:

[0014] A compressor body is internally provided with an interstage axial gas flow channel;

[0015] A first-stage compression assembly is arranged at one end of the compressor body, and the first-stage compression assembly comprises a first-stage impeller and a first-stage volute. The first-stage volute is connected with the compressor body, and the first-stage impeller is arranged in the first-stage volute. An outlet of the first-stage impeller is provided with a diffuser guide, and the diffuser guide is provided with a plurality of guide ribs. The diffuser guide forms a diffuser flow channel between adjacent guide ribs. The guide ribs are inclinedly extended along the direction of the outlet gas flow of the first-stage impeller at the inlet of the diffuser flow channel, and the guide ribs are transitionally extended radially to the diffuser guide at the outlet of the diffuser flow channel.

[0016] In combination with the first aspect, in some implementations of the first aspect, the diffuser guide further comprises an annular back plate, the guide ribs are arranged on one side surface of the annular back plate facing the first-stage volute, and a plurality of the guide ribs are uniformly distributed along the circumference of the annular back plate. The guide ribs are matched with the first-stage volute and define a diffuser flow channel communicated from the outlet of the first-stage impeller to the interstage axial gas flow channel.

[0017] With reference to the first aspect and the above implementation manners, in some implementation manners of the first aspect, a throughflow section of the diffuser passage gradually increases from the inlet end to the outlet end.

[0018] The second aspect is a compressor comprising the inter-stage diffuser structure of any implementation manner of the first aspect.

[0019] With reference to the second aspect, in some implementation manners of the second aspect, further comprising a two-stage compression assembly arranged at the other end of the compressor body, the two-stage compression assembly comprising a two-stage impeller and a two-stage volute, the two-stage volute being connected with the compressor body, and the two-stage impeller being arranged inside the two-stage volute.

[0020] With reference to the second aspect and the above implementation manners, in some implementation manners of the second aspect, the compressor body comprises an outer shell and an inner shell, and the inter-stage axial air flow passage is formed between the inner shell and the outer shell.

[0021] With reference to the second aspect and the above implementation manners, in some implementation manners of the second aspect, further comprising a stator arranged inside the inner shell and a rotor assembly comprising a shaft core and a rotor arranged on the shaft core, the shaft core being supported on the compressor body through a bearing seat assembly, the first-stage impeller being arranged at one end of the shaft core, and the two-stage impeller being arranged at the other end of the shaft core.

[0022] With reference to the second aspect and the above implementation manners, in some implementation manners of the second aspect, a cooling jacket is arranged between the outer circle of the stator and the inner shell.

[0023] With reference to the second aspect and the above implementation manners, in some implementation manners of the second aspect, a turbine energy recovery assembly is arranged outside the two-stage compression assembly.

[0024] The third aspect is a fuel cell system comprising the compressor of any implementation manner of the second aspect.

[0025] One of the above technical solutions has at least one of the following advantages or beneficial effects: In the technical scheme of the utility model, first, the inter-stage axial airflow channel is arranged in the compressor body, which is compact in structure and small in space occupation, and is conducive to improving the volume power density of the fuel cell engine. Meanwhile, a diffuser is arranged between the outlet of the first-stage impeller and the inter-stage axial airflow channel, and the diffuser has the functions of diffusing pressure and guiding flow. On the one hand, the diffuser diffuses the airflow compressed by the first-stage impeller through a diffuser flow channel, thereby improving the static pressure of the airflow. On the other hand, the diffuser guides the rotating airflow at the outlet of the first-stage impeller to be close to the radial and axial airflow at the outlet of the diffuser flow channel, thereby flowing into the inter-stage axial airflow channel, so that the airflow energy loss of airflow redirection is greatly reduced.

[0026] The additional aspects and advantages of the utility model will be partially given in the following description, some will become obvious from the following description, or be understood through the practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0027] The above and / or additional aspects and advantages of the utility model will become apparent and more readily appreciated from the following description of the embodiments, with reference to the following drawings, in which:

[0028] Figure 1 is an embodiment structure schematic view of the compressor of the utility model;

[0029] Figure 2 is an embodiment diffuser structure schematic view of the utility model;

[0030] Figure 3 is an embodiment diffuser and first-stage impeller assembly state schematic view of the utility model. DETAILED DESCRIPTION

[0031] This part will describe the specific embodiments of the utility model in detail, and the preferred embodiments of the utility model are shown in the drawings, and the drawings are used to supplement the description of the text part, so that people can intuitively and visually understand each technical feature and the overall technical scheme of the utility model, but it cannot be understood as the limitation of the protection scope of the utility model.

[0032] In the utility model, if the direction (up, down, left, right, front and back) is described, it is only for the convenience of describing the technical scheme of the utility model, and is not indicative or suggestive of the technical features indicated must have a specific orientation, a specific orientation structure and operation, therefore, it cannot be understood as the limitation of the utility model.

[0033] In the utility model, the meaning of "several" is one or more, the meaning of "multiple" is two or more, and "greater than", "less than", "exceed" and the like are understood as not including the number; "above", "below", "within" and the like are understood as including the number. In the description of the utility model, if "first" and "second" are described, they are only used for distinguishing technical features for the purpose, and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the sequence of indicated technical features.

[0034] In the utility model, unless otherwise explicitly limited, the words such as "arrange", "install", "connect" and the like should be understood in a broad sense, for example, can be directly connected, can also be indirectly connected through an intermediate medium; can be fixedly connected, can also be detachably connected, can also be integrally formed; can be mechanically connected, can also be electrically connected or capable of intercommunication; can be the communication or interaction relationship between two elements inside two elements. The person skilled in the art can reasonably determine the specific meaning of the above words in the utility model in combination with the specific content of the technical scheme.

[0035] Referring to Figure 1 、 Figure 2 、 Figure 3 The embodiment of the utility model provides a compressor interstage pressure recovery flow guide structure for the pressure recovery and flow guide of gas between the multistage compression assembly of the compressor, the compressor interstage pressure recovery flow guide structure comprises a compressor body 100 and a primary compression assembly 200, the compressor body 100 is internally provided with an interstage axial airflow channel 101, and the interstage axial airflow channel 101 is communicated between two compression assemblies of the compressor.

[0036] The primary compression assembly 200 is used for carrying out first centrifugal acceleration to air and sending into the interstage axial airflow channel 101, the primary compression assembly 200 is arranged at one end of the compressor body 100, the primary compression assembly 200 comprises a primary impeller 201 and a primary volute 202, the primary volute 202 is connected with the compressor body 100, the primary impeller 201 is arranged inside the primary volute 202, and the outlet of the primary impeller 201 is provided with a pressure recovery flow guide 300 between the interstage axial airflow channel 101, the pressure recovery flow guide 300 is provided with a plurality of flow guide ribs 301, the pressure recovery flow guide 300 forms a pressure recovery flow channel 302 between adjacent flow guide ribs 301, the flow guide rib 301 extends along the outlet airflow direction of the primary impeller 201 at the inlet of the pressure recovery flow channel 302, and the flow guide rib 301 extends to the radial transition of the pressure recovery flow guide 300 at the outlet of the pressure recovery flow channel 302.

[0037] In combination with Figures 1-3The technical scheme of the utility model discloses first set up interstage axial airflow channel 101 in the compressor body 100, compact structure, small space occupation, be favorable to improving the volume power density of fuel cell engine. Meanwhile, the diffuser 300 is arranged between the outlet of the first impeller 201 and the interstage axial airflow channel 101, the diffuser 300 has the functions of diffusing pressure and guiding flow, on the one hand, the diffuser 300 diffuses the airflow compressed by the first impeller 201 through the diffuser flow channel 302, improves the static pressure of the airflow, on the other hand, the diffuser 300 guides the rotating airflow at the outlet of the first impeller 201 to be the airflow close to radial and axial at the outlet of the diffuser flow channel 302, and the airflow flows into the interstage axial airflow channel 101, thereby greatly reducing the airflow energy loss of airflow redirection.

[0038] In some embodiments, referring to Figure 1 、 Figure 2 、 Figure 3 The diffuser 300 further includes an annular back plate 303, the annular back plate 303 is sleeved outside the first impeller 201, the flow guide rib plate 301 is arranged on the side surface of the annular back plate 303 facing the first volute 202, a plurality of flow guide rib plates 301 are uniformly distributed along the circumference of the annular back plate 303, the flow guide rib plate 301 cooperates with the first volute 202, and the diffuser flow channel 302 communicated from the outlet of the first impeller 201 to the interstage axial airflow channel 101 is defined. The outer edge of the first volute 202 is curved towards the compressor body 100, further cooperates with the flow guide rib plate 301, guides the rotating airflow at the outlet of the first impeller 201 to be the airflow close to radial and axial at the outlet of the diffuser flow channel 302.

[0039] In some embodiments, referring to Figure 2 The through-flow section of the diffuser flow channel 302 gradually increases from the inlet end to the outlet end. The diffuser flow channel 302 diffuses the airflow compressed by the first impeller 201, and improves the static pressure of the airflow.

[0040] Referring to Figure 1 The embodiment of the utility model further provides a compressor which comprises the interstage diffuser flow structure of the compressor in any one of the above embodiments.

[0041] Referring to Figure 1 The compressor further comprises a second compression assembly 400, the second compression assembly 400 is used for centrifugally accelerating air for the second time on the basis of the first compression assembly 200, the second compression assembly 400 is arranged at the other end of the compressor body 100, the second compression assembly 400 comprises a second impeller 401 and a second volute 402, the second volute 402 is connected with the compressor body 100, and the second impeller 401 is arranged inside the second volute 402.

[0042] The inter-stage axial air flow passage 101 can be formed by providing axial holes in the compressor body 100.

[0043] In some embodiments, referring to Figure 1 , the compressor body 100 is a double-layer structure, and the compressor body 100 comprises an outer shell 102 and an inner shell 103, the inner shell 103 is installed in the outer shell 102, and the inter-stage axial air flow passage 101 is formed between the inner shell 103 and the outer shell 102. In this embodiment, the inter-stage axial air flow passage 101 is directly formed through the double-layer structure of the compressor body 100, and the resistance is smaller, so that the energy loss of the inter-stage axial air flow passage 101 to the air flow can be effectively reduced.

[0044] Further, in some embodiments, referring to Figure 1 , the compressor further comprises a stator 501 and a rotor assembly 502, the stator 501 is arranged in the inner shell 103, the rotor assembly 502 comprises a shaft core and a rotor arranged on the shaft core, the shaft core is supported on the compressor body 100 through a bearing seat assembly, a first-stage impeller 201 is arranged at one end of the shaft core, and a second-stage impeller 401 is arranged at the other end of the shaft core. The stator 501 and the rotor assembly 502 are cooperated with each other to synchronously drive the first-stage compression assembly 200 and the second-stage compression assembly 400, so that the air centrifugally accelerated by the first-stage impeller 201 is introduced into the second-stage impeller 401 for centrifugal acceleration.

[0045] In some embodiments, referring to Figure 1 , a cooling jacket 104 is arranged between the outer circle of the stator 501 and the inner shell 103, the cooling jacket 104 is located in the inner shell 103 of the compressor, and the cooling jacket 104 is located on the inner side of the inter-stage axial air flow passage 101. In this embodiment, the cooling water groove is arranged in the inter-stage axial air flow passage 101, and the cooling liquid flowing through the cooling jacket 104 can cool the air in the inter-stage axial air flow passage 101, so that the second-stage inlet air temperature is reduced, and the second-stage compression efficiency is improved.

[0046] In some embodiments, referring to Figure 1 , the compressor body 100 is provided with a turbine energy recovery assembly 600 outside the second-stage compression assembly 400.

[0047] Embodiments of the utility model also provide a fuel cell system, which comprises the compressor in any one of the above embodiments.

[0048] In the description of the present specification, the description referring to the terms "example", "embodiment" or "some embodiments" or 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 present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0049] Of course, the present application is not limited to the above-described embodiments, and those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the present application, and these equivalent modifications or substitutions are included in the scope defined by the claims of the present application.

Claims

1. An inter-stage diffuser for a compressor, characterized in that, The compressor body is internally provided with an inter-stage axial air flow passage; The first-stage compression assembly is arranged at one end of the compressor body, and comprises a first-stage impeller and a first-stage volute. The first-stage volute is connected with the compressor body, and the first-stage impeller is arranged inside the first-stage volute. An outlet of the first-stage impeller is provided with a diffuser guide vane between the diffuser guide vane and the inter-stage axial air flow passage. The diffuser guide vane is provided with a plurality of guide ribs, and the diffuser guide vane forms a diffuser flow channel between adjacent guide ribs. The guide ribs are inclinedly extended along the outlet air flow direction of the first-stage impeller at the inlet of the diffuser flow channel, and the guide ribs are transitionally extended radially to the diffuser guide vane at the outlet of the diffuser flow channel. The diffuser guide vane further comprises an annular back plate, and the guide ribs are arranged on one side surface of the annular back plate facing the first-stage volute. The plurality of guide ribs are uniformly distributed along the circumference of the annular back plate. The guide ribs cooperate with the first-stage volute to define a diffuser flow channel communicated from the outlet of the first-stage impeller to the inter-stage axial air flow passage.

2. The compressor inter-stage diffuser of claim 1, wherein, The through-flow section of the diffuser flow channel gradually increases from the inlet end to the outlet end.

3. The compressor interstage diffuser of claim 1, wherein, The compressor inter-stage diffuser guide structure of claim 1, 2 or 3.

4. A compressor characterized by, The compressor further comprises a second-stage compression assembly arranged at the other end of the compressor body. The second-stage compression assembly comprises a second-stage impeller and a second-stage volute. The second-stage volute is connected with the compressor body, and the second-stage impeller is arranged inside the second-stage volute.

5. The compressor of claim 4, wherein, The compressor body comprises an outer shell and an inner shell. The inter-stage axial air flow passage is formed between the inner shell and the outer shell.

6. The compressor of claim 5, wherein, The compressor further comprises a stator arranged in the inner shell and a rotor assembly comprising a shaft core and a rotor arranged on the shaft core. The shaft core is supported on the compressor body through a bearing seat assembly. The first-stage impeller is arranged at one end of the shaft core, and the second-stage impeller is arranged at the other end of the shaft core.

7. The compressor of claim 6, wherein, A cooling jacket is arranged between the outer circle of the stator and the inner shell.

8. The compressor of claim 7, wherein, The compressor body is provided with a turbine energy recovery assembly outside the second-stage compression assembly.

9. The compressor of claim 7, wherein, The compressor of any one of claims 4 to 9.

10. A fuel cell system characterized by comprising: ​

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