A fuel cell engine and aircraft

Abstract

The fuel cell engine and the aircraft disclosed by the application relate to the field of fuel cells, comprising a fuel cell stack and a turbofan engine, the fuel cell stack comprising a plurality of parallelly arranged hot plate type bipolar plates, the hot plate type bipolar plate having a hot plate structure. In the length direction, the two ends of the hot plate type bipolar plate have a heating area and a heat dissipation area respectively, and a membrane electrode is arranged between the heating areas of any two adjacent hot plate type bipolar plates, the heat generated by the operation of the membrane electrode being absorbed by the heating area of the hot plate type bipolar plate and then diffused to the environment by the heat dissipation area. The turbofan engine has an outer channel, and the heat dissipation area of the hot plate type bipolar plate is used for forced heat exchange by the airflow flowing through the outer channel. The hot plate type bipolar plate is forced to perform convective heat exchange by the large airflow of the outer channel of the turbofan engine, which greatly improves the convective heat exchange efficiency of the hot plate type bipolar plate, so that the fuel cell can still maintain a relatively low operating temperature under a very high operating current density, and the use efficiency is higher.

Description

Technical Field

[0001] This invention relates to the field of fuel cell technology, and more specifically, to a fuel cell engine and an aircraft. Background Technology

[0002] A fuel cell stack is a structure composed of a sandwich structure consisting of multiple bipolar plates and membrane electrode assemblies (MEAs). The function of the bipolar plates is to transport reactant gases, commonly hydrogen and air, through gas channels to the active region of the MEA, enabling the electrochemical reaction to occur and generate an electric current. Simultaneously, the bipolar plates also play a role in electron transfer. Furthermore, the sealing structure on the bipolar plates keeps the gas within the reaction zone, preventing leakage to the external environment.

[0003] A fuel cell stack employing a vapor chamber-type bipolar plate cooling system combines a vapor chamber with a bipolar plate, replacing the traditional bipolar plate's cooling cavity (air-cooled or water-cooled) with a closed cavity filled with a phase change medium. For example... Figure 2 As shown, the heating area of ​​the vapor chamber bipolar plate has a gas flow channel design, where air and hydrogen flow into the cathode and anode chambers respectively, where an electrochemical reaction occurs to generate electrical energy; the internal cavity is similar to a vapor chamber design, with the internal vacuum cavity filled with a phase change medium; the heat dissipation area is used to diffuse heat into the environment.

[0004] like Figure 1 As shown, existing fuel cell stacks generally use air-cooled or water-cooled systems for heat dissipation. The cooling system generally includes a cooling fan 300, radiator, water circuit, coolant and other structures. This type of cooling system is relatively heavy and has a low power-to-weight ratio, making it unsuitable for the power requirements of the aerospace field.

[0005] Therefore, how to cool the fuel cell stack and improve the power-to-weight ratio of the system has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the object of the present invention is to provide a fuel cell engine to achieve cooling of the fuel cell stack and improve the power-to-weight ratio of the system.

[0007] Another object of the present invention is to provide an aircraft comprising the above-described fuel cell engine.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A fuel cell engine, comprising:

[0010] A fuel cell stack includes multiple parallel heat-spreading bipolar plates. Each heat-spreading bipolar plate has a heat-spreading plate structure. Along the length direction, each heat-spreading bipolar plate has a heat-generating area and a heat-dissipating area at both ends. A membrane electrode is disposed between the heat-generating areas of any two adjacent heat-spreading bipolar plates.

[0011] A turbofan engine having an outer bypass duct, wherein the heat dissipation area is forcibly heat-exchanged by the airflow flowing through the outer bypass duct.

[0012] Optionally, in the above-described fuel cell engine, the outer bypass duct is connected to the fuel cell stack via a heat exchange pipe, and the outlet of the heat exchange pipe faces the heat dissipation area.

[0013] Optionally, in the above-mentioned fuel cell engine, the fuel cell stacks are multiple in parallel and are radially evenly distributed with the axis of the heat exchange pipe as the center, and the heat dissipation area of ​​each heat-spreading bipolar plate is closer to the axis of the heat exchange pipe than the heat-generating area.

[0014] Optionally, in the above-described fuel cell engine, the length of the heat dissipation area of ​​the heat-spreading plate bipolar plate located in the middle of the fuel cell stack is greater than the length of the heat dissipation area of ​​the heat-spreading plate bipolar plate located at both ends.

[0015] Optionally, in the above-described fuel cell engine, the fuel cell stack consists of three or four units connected in parallel.

[0016] Optionally, in the above-described fuel cell engine, the heat spreader bipolar plate includes:

[0017] Anode plate;

[0018] A cathode plate is connected to the anode plate and forms a vacuum-sealed cavity. The vacuum-sealed cavity is filled with a phase change medium, which is used to absorb the heat from the heating area and transfer it to the heat dissipation area for heat dissipation.

[0019] A capillary wick is disposed on the inner wall of the vacuum-sealed cavity.

[0020] Optionally, in the above-mentioned fuel cell engine, the heating area includes a first heating area located at the first end of the anode plate and a second heating area located at the first end of the cathode plate. The first heating area and the second heating area are opposite to each other and are both used to be in contact with the membrane electrode.

[0021] The heat dissipation area includes a first heat dissipation area located at the second end of the anode plate and a second heat dissipation area located at the second end of the cathode plate, and the first heat dissipation area and the second heat dissipation area are opposite to each other.

[0022] Optionally, in the above-mentioned fuel cell engine, the outer walls of the first heating region and the second heating region are provided with a plurality of strip-shaped protrusions, and a gas flow channel for gas to pass through is formed between two adjacent strip-shaped protrusions. The first heating region and the second heating region are attached to the membrane electrode through the strip-shaped protrusions.

[0023] Optionally, in the above-described fuel cell engine, the spacing between any two adjacent heat spreader bipolar plates in each of the fuel cell stacks is equal; and / or,

[0024] The heat-generating area is located on one side of the heat-dissipating area, and the airflow in the outer duct flows from the first end to the second end of the heat-dissipating area.

[0025] An aircraft characterized by comprising the aforementioned fuel cell engine.

[0026] The fuel cell engine provided by this invention includes a fuel cell stack and a turbofan engine. The fuel cell stack includes multiple parallel-arranged vapor chamber bipolar plates. Each vapor chamber bipolar plate has a vapor chamber structure, combining heat transfer and heat dissipation functions, and possesses an ultra-high thermal conductivity coefficient. Along its length, each vapor chamber bipolar plate has a heating region and a heat dissipation region at both ends. A membrane electrode assembly (MEA) is disposed between the heating regions of any two adjacent vapor chamber bipolar plates. The heat generated by the MEA operation is absorbed by the heating region of the vapor chamber bipolar plate and then diffused into the environment through the heat dissipation region. The turbofan engine has an outer bypass duct, and the heat dissipation region of the vapor chamber bipolar plate is used for forced heat exchange by the airflow flowing through the outer bypass duct. By forcing convective heat exchange through the large airflow of the turbofan engine's outer bypass duct, the convective heat exchange efficiency of the vapor chamber bipolar plate is greatly improved, allowing the fuel cell to maintain a low operating temperature even under extremely high operating voltage, resulting in higher efficiency and improved system performance.

[0027] Compared to existing technologies, the fuel cell engine provided by this invention combines a vapor chamber-type fuel cell stack with a turbofan engine in aviation power. It is applicable to engine system integration solutions in the aviation field. Utilizing the fuel cell stack as the driving force for aviation can effectively reduce the power consumption of the turbofan engine and reduce carbon emissions. At the same time, while using a vapor chamber-type bipolar plate to dissipate heat from the stack, the airflow from the turbofan engine's bypass duct enables forced convection heat transfer to the vapor chamber-type bipolar plate, which can quickly dissipate the heat generated by the fuel cell stack. This eliminates the need for a cooling system in traditional fuel cell stacks, greatly reducing system weight and improving the system's power-to-weight ratio. Furthermore, it enables the utilization of gas within the turbofan engine's bypass duct, improving the overall gas utilization rate, as well as the overall energy utilization rate and efficiency of the system.

[0028] The aircraft provided by this invention includes the aforementioned fuel cell engine, and therefore also possesses the aforementioned advantages, which will not be repeated here. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of heat dissipation in a fuel cell stack in the prior art;

[0031] Figure 2 This is a schematic diagram of the structure of the heat spreader bipolar plate disclosed in an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of the structure of a fuel cell disclosed in an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the first structure of the fuel cell engine disclosed in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of a second structure of the fuel cell engine disclosed in an embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of the structure of a fuel cell stack disclosed in an embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of a third structure of the fuel cell engine disclosed in an embodiment of the present invention;

[0037] Figure 8 This is a schematic diagram of the fourth structure of the fuel cell engine disclosed in the embodiments of the present invention.

[0038] Among them, 100 is the fuel cell stack, 110 is the heat spreader bipolar plate, 111 is the heat generation area, 112 is the heat dissipation area, 113 is the capillary wick, 114 is the anode plate, 115 is the cathode plate, and 116 is the gas flow channel.

[0039] 120 is the membrane electrode, 121 is the gas diffusion layer, 122 is the proton exchange membrane, and 123 is the catalyst layer;

[0040] The 200 is a turbofan engine;

[0041] 300 is a cooling fan. Detailed Implementation

[0042] The core of this invention is to disclose a fuel cell engine to cool the fuel cell stack and improve the power-to-weight ratio of the system.

[0043] Another key aspect of this invention is the disclosure of an aircraft comprising the aforementioned fuel cell engine.

[0044] Hereinafter, embodiments will be described with reference to the accompanying drawings. Furthermore, the embodiments shown below do not limit the scope of the invention as described in the claims. Additionally, the complete contents of the structures represented in the embodiments below are not limited to those necessary for the solution of the invention as described in the claims. It should be noted that, for ease of description, only the parts relevant to the relevant application are shown in the drawings. Unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0045] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "a," and / or "the" are not specifically singular and may include the plural. Generally, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements. An element defined by the phrase "comprising an..." does not exclude the presence of other identical elements in the process, method, product, or apparatus that includes the element.

[0046] The fuel cell engine disclosed in this embodiment of the invention includes a fuel cell stack 100 and a turbofan engine 200, combined with... Figure 3 The fuel cell stack 100 includes multiple parallel-arranged heat spreader bipolar plates 110. Each heat spreader bipolar plate 110 has a heat spreader structure, combining heat transfer and heat dissipation functions, and possesses an ultra-high thermal conductivity coefficient. Along its length, each end of the heat spreader bipolar plate 110 has a heating region 111 and a heat dissipation region 112. A membrane electrode 120 is disposed between the heating regions 111 of any two adjacent heat spreader bipolar plates 110. The heat generated by the membrane electrode 120 during operation is absorbed by the heating regions 111 of the heat spreader bipolar plate 110 and then diffused into the environment through the heat dissipation regions 112.

[0047] The turbofan engine 200 has an outer bypass duct, and the heat dissipation area 112 of the heat sink bipolar plate 110 is used for forced heat exchange by the airflow flowing through the outer bypass duct. By forcing convective heat exchange through the large airflow of the turbofan engine 200's outer bypass duct, the convective heat exchange efficiency of the heat sink bipolar plate 110 is greatly improved, enabling the fuel cell to maintain a low operating temperature even under extremely high operating voltage, resulting in higher efficiency and improved system performance.

[0048] Compared to existing technologies, the fuel cell engine disclosed in this invention combines a vapor chamber-type fuel cell stack 100 with a turbofan engine 200 in aviation power. This makes it suitable for engine system integration solutions in the aviation field. Utilizing the fuel cell stack 100 as the driving force for aviation effectively reduces the power consumption and carbon emissions of the turbofan engine 200. Simultaneously, while using a vapor chamber-type bipolar plate 110 to dissipate heat from the stack, the airflow from the turbofan engine 200's bypass duct forces convection heat exchange onto the vapor chamber-type bipolar plate 110, rapidly dissipating the heat generated by the fuel cell stack 100. This eliminates the need for a traditional cooling system in fuel cell stacks, significantly reducing system weight and improving the system's power-to-weight ratio. Furthermore, it enables the utilization of gas within the turbofan engine 200's bypass duct, improving gas utilization efficiency and the overall energy utilization and efficiency of the system.

[0049] Specifically, the outer bypass duct is connected to the location of the fuel cell stack 100 via a heat exchange pipe, and the outlet of the heat exchange pipe faces the heat dissipation area 112.

[0050] Among them, the fuel cell stack 100 can be installed on the aircraft equipment near the turbofan engine 200 to reduce the impact of the installation of heat exchange pipes on the existing aircraft equipment layout.

[0051] The fuel cell engine disclosed in this invention has high heat exchange efficiency, enabling the fuel cell to operate at power levels that traditional air cooling cannot achieve. It can completely replace traditional water cooling or air cooling systems, thereby simplifying system design, reducing system weight, increasing system power-to-weight ratio, and better meeting the needs of aviation power.

[0052] Those skilled in the art will understand that, since the power requirements of aviation propulsion are typically high, generally exceeding 300kW-500kW, while the power of a single traditional fuel cell stack is generally around 100kW, multiple fuel cell stacks are typically connected in parallel to increase power. Furthermore, because the peak power requirements of aviation propulsion are usually much greater than the power of fuel cells, the combination of fuel cells and turbofan engines is a more preferable option for aviation propulsion. Fuel cells can also be used to power electronic equipment on aircraft.

[0053] Specifically, the fuel cell engine may include one or more fuel cell stacks 100.

[0054] In a specific embodiment of the present invention, the fuel cell engine includes multiple fuel cell stacks 100 connected in parallel, and combined with... Figure 4 and Figure 5Multiple fuel cell stacks 100 are radially and uniformly distributed around the axis of the heat exchange pipe, and the heat dissipation area 112 of each heat exchange plate bipolar plate 110 is closer to the axis of the heat exchange pipe than the heat generation area 111. The bypass gas from the turbofan engine 200 can be directly blown onto the heat dissipation area 112 of the heat exchange plate bipolar plate 110 through the heat exchange pipe, achieving forced convection heat transfer.

[0055] It should be noted that the axis of the heat exchange pipe mentioned above refers to the axis of the section of pipe near the outlet, so that the multiple fuel cell stacks 100 are radially and evenly distributed around the outlet axis.

[0056] For ease of production, the structures of each vapor chamber bipolar plate 110 can be identical. However, because the membrane electrode 120, located in the middle, has a higher temperature, the heat dissipation of this type of equal-length vapor chamber bipolar plate 110 stack is relatively poor. Furthermore, since the cross-section of the heat exchange pipes is generally circular or rectangular, the layout of the equal-length vapor chamber bipolar plate 110 stack must consider the uniform heat dissipation of each fuel cell stack 100, generally using... Figure 4 and Figure 5 The layout shown has low integration, with a large gap in the middle of the heat exchange pipes.

[0057] Therefore, in order to improve heat exchange efficiency, the heat exchange area of ​​the heat dissipation region 112 of the heat-spreading plate bipolar plate 110 located in the middle of the fuel cell stack 100 can be designed to be larger than the heat exchange area of ​​the heat dissipation region 112 of the heat-spreading plate bipolar plate 110 located at both ends.

[0058] In a specific embodiment disclosed in this invention, such as Figure 6 As shown, the length of the heat dissipation area 112 of the heat sink 110 located in the middle of the fuel cell stack 100 is ( Figure 2 The length of the heat dissipation area 112 of the heat dissipation plate type bipolar plate 110 located at both ends is greater than that of the left and right direction shown, so that the heat dissipation end of each fuel cell stack 100 forms a length layout scheme with a longer middle and shorter ends.

[0059] Compared to the arrangement of equal-length homogenized bipolar plates 110, the above-mentioned homogenized bipolar plates 110 with a longer middle and shorter ends result in a higher integration of the fuel cell stack 100. Furthermore, the longer homogenized bipolar plates 110 in each fuel cell stack 100 can utilize the gaps in the heat exchange pipes, making fuller use of the bypass ventilation of the turbofan engine 200.

[0060] Furthermore, since the heat dissipation area 112 of the heat-spreading bipolar plate 110 located in the center is longer and the heat exchange area is larger, it can more effectively dissipate heat from the membrane electrode 120 located in the middle of the fuel cell stack 100, thereby improving the temperature uniformity of each membrane electrode 120 in the fuel cell stack 100.

[0061] For example, fuel cell stack 100 can consist of three or four units connected in parallel, and in a manner such as... Figure 7 or Figure 8 The arrangement shown is designed to efficiently utilize the high-speed bypass gas from the turbofan engine 200, thereby improving system efficiency.

[0062] Furthermore, such as Figure 6 As shown, the homogenized bipolar plates 110 of each fuel cell stack 100 are arranged symmetrically with the longest homogenized bipolar plate 110 (one or two) as the center.

[0063] In a specific embodiment disclosed in this invention, such as Figure 2 As shown, the heat spreader bipolar plate 110 includes an anode plate 114, a cathode plate 115, and a capillary wick 113. The cathode plate 115 is connected to the anode plate 114 and forms a vacuum-sealed cavity. The vacuum-sealed cavity is filled with a phase change medium, which absorbs heat from the heating region 111 and transfers it to the heat dissipation region 112 for diffusion. The capillary wick 113 is disposed on the inner wall of the vacuum-sealed cavity.

[0064] Specifically, the heating region 111 includes a first heating region located at the first end of the anode plate 114 and a second heating region located at the first end of the cathode plate 115. The first heating region and the second heating region are opposite to each other, and both the first heating region and the second heating region are used to be attached to the membrane electrode 120. The first heating region or the second heating region located at the end is used to be attached to the housing of the fuel cell stack 100.

[0065] The membrane electrode 120 includes structures such as a gas diffusion layer 121, a catalyst layer 123, and a proton exchange membrane 122, which are existing technologies and will not be described in detail here.

[0066] The heat dissipation area 112 includes a first heat dissipation area located at the second end of the anode plate 114 and a second heat dissipation area located at the second end of the cathode plate 115. The first and second heat dissipation areas are opposite each other and exchange heat with the airflow in the heat exchange pipe. The first and second heat dissipation areas located at the ends are used to fit against the housing of the fuel cell stack 100.

[0067] like Figure 3As shown, the membrane electrode 120 is attached to the first heating region and the second heating region. Both the first heat dissipation region and the second heat dissipation region extend out of the fuel cell stack so that they can be cooled by natural air or by forced convection cooling by the turbofan engine 200, thereby dissipating the heat generated by the membrane electrode 120 inside the fuel cell stack into the environment.

[0068] As shown in Figure 2, multiple strip-shaped protrusions are provided on the outer walls of the first and second heating regions, and gas flow channels 116 are formed between adjacent strip-shaped protrusions for gas passage. The gas flow channels 116 form an anodic flow field in the first heating region and a cathode flow field in the second heating region. Each end of a membrane electrode 120 corresponds to an anodic flow field and a cathode flow field, respectively. Air and hydrogen flow into the cathode and anodic flow fields, respectively, where electrochemical reactions occur and electrical energy is generated.

[0069] The first and second heating areas are attached to the membrane electrode 120 through strip-shaped protrusions.

[0070] Furthermore, the spacing between any two adjacent heat spreader bipolar plates 110 in each fuel cell stack 100 is equal to facilitate production and assembly.

[0071] Combination Figure 4 The heating area 111 is located on one side of the heat dissipation area 112. The cooling airflow in the heat exchange pipe flows from the first end to the second end of the heat dissipation area 112, so that the airflow can pass through the gap between each heat exchange plate electrode 110 for heat exchange. That is, the airflow flows in a direction perpendicular to the heating area 111 to the heat dissipation area 112.

[0072] The aircraft disclosed in this embodiment of the invention includes the aforementioned fuel cell engine, and therefore also possesses the aforementioned advantages, which will not be repeated here.

[0073] The terms "first" and "second," etc., used in the specification and claims of this invention are used to distinguish different objects, not to describe a specific order, and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, in the description of embodiments in this application, "a plurality of" refers to two or more.

[0074] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fuel cell engine, characterized in that, include: The fuel cell stack (100) includes a plurality of parallel heat-spreading bipolar plates (110). Each heat-spreading bipolar plate (110) has a heat-spreading plate structure. Along the length direction, each heat-spreading bipolar plate (110) has a heat-generating region (111) and a heat-dissipating region (112) at its two ends. A membrane electrode (120) is disposed between the heat-generating regions (111) of any two adjacent heat-spreading bipolar plates (110). The turbofan engine (200) has an outer bypass duct, and the heat dissipation area (112) is used for forced heat exchange by the airflow flowing through the outer bypass duct; The outer bypass duct is connected to the fuel cell stack (100) via a heat exchange pipe, and the outlet of the heat exchange pipe faces the heat dissipation area (112). The fuel cell stack (100) consists of multiple stacks connected in parallel and is radially evenly distributed with the axis of the heat exchange pipe as the center. The heat dissipation area (112) of each heat-spreading bipolar plate (110) is closer to the axis of the heat exchange pipe than the heat-generating area (111). The length of the heat dissipation area (112) of the heat-spreading plate bipolar plate (110) located in the middle of the fuel cell stack (100) is greater than the length of the heat dissipation area (112) of the heat-spreading plate bipolar plate (110) located at both ends.

2. The fuel cell engine as described in claim 1, characterized in that, The fuel cell stack (100) consists of three or four units connected in parallel.

3. The fuel cell engine according to any one of claims 1-2, characterized in that, The heat spreader bipolar plate (110) includes: Anode plate (114); The cathode plate (115) is connected to the anode plate (114) and forms a vacuum-sealed cavity. The vacuum-sealed cavity is filled with a phase change medium, which is used to absorb the heat of the heating area (111) and transfer it to the heat dissipation area (112) for heat dissipation. A capillary wick (113) is disposed on the inner wall of the vacuum-sealed cavity.

4. The fuel cell engine as described in claim 3, characterized in that, The heating area (111) includes a first heating area located at the first end of the anode plate (114) and a second heating area located at the first end of the cathode plate (115). The first heating area and the second heating area are opposite to each other and are both used to attach to the membrane electrode (120). The heat dissipation area (112) includes a first heat dissipation area located at the second end of the anode plate (114) and a second heat dissipation area located at the second end of the cathode plate (115), and the first heat dissipation area and the second heat dissipation area are opposite to each other.

5. The fuel cell engine as described in claim 4, characterized in that, The outer walls of the first heating area and the second heating area are provided with multiple strip-shaped protrusions, and a gas flow channel (116) for gas to pass through is formed between two adjacent strip-shaped protrusions. The first heating area and the second heating area are attached to the membrane electrode (120) through the strip-shaped protrusions.

6. The fuel cell engine as described in claim 1, characterized in that, The spacing between any two adjacent heat spreader bipolar plates (110) in each of the aforementioned fuel cell stacks (100) is equal; and / or, The heat-generating area (111) is located on one side of the heat-dissipating area (112), and the airflow in the outer duct flows from the first end to the second end of the heat-dissipating area (112).

7. An aircraft, characterized in that, Including the fuel cell engine as described in any one of claims 1-6.

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