CN112084685B - Method for establishing microscopic model of catalyst layer and application - Google Patents
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- 239000003054 catalyst Substances 0.000 title claims abstract description 93
- 238000000034 method Methods 0.000 title claims abstract description 27
- 238000004458 analytical method Methods 0.000 claims abstract description 17
- 239000012528 membrane Substances 0.000 claims abstract description 12
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 64
- 239000002245 particle Substances 0.000 claims description 51
- 229920000557 Nafion® Polymers 0.000 claims description 18
- 229910052697 platinum Inorganic materials 0.000 claims description 17
- 239000000463 material Substances 0.000 claims description 13
- 239000011159 matrix material Substances 0.000 claims description 12
- 229910052799 carbon Inorganic materials 0.000 claims description 8
- 230000008569 process Effects 0.000 claims description 8
- 239000002131 composite material Substances 0.000 claims description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 5
- 239000003792 electrolyte Substances 0.000 claims description 5
- 230000000737 periodic effect Effects 0.000 claims description 5
- 230000001066 destructive effect Effects 0.000 claims description 4
- 238000004422 calculation algorithm Methods 0.000 claims description 3
- 230000003197 catalytic effect Effects 0.000 claims description 3
- 230000000694 effects Effects 0.000 claims 1
- 230000001747 exhibiting effect Effects 0.000 claims 1
- 239000000446 fuel Substances 0.000 abstract description 16
- 238000011160 research Methods 0.000 abstract description 9
- 230000006872 improvement Effects 0.000 abstract description 5
- 238000004088 simulation Methods 0.000 abstract description 5
- 230000000704 physical effect Effects 0.000 abstract description 3
- 238000009826 distribution Methods 0.000 description 5
- 230000008859 change Effects 0.000 description 4
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- 238000006731 degradation reaction Methods 0.000 description 3
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- 238000005457 optimization Methods 0.000 description 2
- 239000012495 reaction gas Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000000109 continuous material Substances 0.000 description 1
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- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/23—Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
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- G06T17/205—Re-meshing
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
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Abstract
The invention relates to a method for establishing a microscopic model of a catalyst layer and application thereof, wherein the method for establishing the microscopic model of the catalyst layer comprises the following steps: s1, performing model assumption and geometric setting on a catalyst layer to obtain a catalyst layer model; s2, establishing a representative volume unit model of the catalyst layer based on the obtained catalyst layer model; s3, finite element analysis is carried out on the representative volume unit. Compared with the prior art, the method has the advantages that the actual microstructure and mechanical property of the catalyst layer are used as the basis, the three-dimensional finite element model of the catalyst layer is built, the influence of different microstructures and actual working conditions on the mechanical property of the catalyst layer is further researched, and the rule of improving the performance of the catalyst layer is analyzed, so that model reference is provided for optimizing the microstructure and mechanical property of the proton exchange membrane fuel cell, and the improvement of the performance of the cell is facilitated; the invention can also be used for simulation research of the relationship between the microstructure and the physical property of the catalyst layer under different use conditions.
Description
Technical Field
The invention relates to the field of fuel cells, in particular to a method for establishing a microscopic model of a catalyst layer and application thereof.
Background
The catalyst layer is one of the core components of the proton exchange membrane fuel cell, is a place where the electrode reaction of the fuel cell occurs, and generally consists of Pt/C catalyst, polymer electrolyte (Nafion), water, and the like. The catalyst particles are reactive sites, the polymer electrolyte serving as a carrier transmits protons, the pores of the catalyst layer form a transmission channel for the reaction gas and the product water to be communicated, a three-phase region formed by the contact of the catalyst, the electrolyte and the reaction gas is a main place for reaction, and the microstructure and the performance of the catalyst layer determine the performance and the cycle life of the fuel cell.
The Pt/C catalyst and the polymer electrolyte can be mechanically degraded in the use process, and the mechanical degradation of the catalyst layer is mainly represented by the occurrence of defects such as thickness thinning, cracks or pinholes, layering or dislocation phenomenon between the catalyst layer and the gas diffusion layer, and the like, which are main reasons for causing the degradation and failure of the catalyst layer.
The proton exchange membrane fuel cell material is difficult to analyze by an experimental method, and the computer simulation calculation not only can save resources and bring convenience to research, but also can endow the computing material with different fields of view and directions for research due to the multiple types and the opening performance of the computer technology. Currently, researchers have built some common models of catalyst layers on an experimental basis to aid in analysis, such as: interface model, microscopic and single hole model, simple macroscopic homogeneous model, embedded macroscopic homogeneous model, agglomerate model, etc. However, simulation experiments on the structure and performance of the model by using computer simulation calculation are rarely studied. CN106407621a discloses a method for establishing a two-dimensional finite element model of a solid oxide fuel cell, and 5 solid oxide fuel cell units with different anode electrolyte geometric interfaces are studied.
Therefore, to realize the study of the mechanical degradation mechanism of the catalyst layer in the proton exchange membrane fuel cell, it is needed to develop a computer establishment method of the three-dimensional micro-geometry model of the catalyst layer of the proton exchange membrane fuel cell.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a method for establishing a microscopic model of a catalyst layer and application thereof, wherein the establishment of the microscopic model of the catalyst layer is realized by establishing a representative volume unit model of the catalyst layer and carrying out finite element analysis on the representative volume unit model, and the microscopic model of the catalyst layer is applied to research on stress distribution in the catalyst layer under the action of external pressure, so that the law of improving the structural performance and mechanical performance of the catalyst layer is analyzed.
The aim of the invention can be achieved by the following technical scheme:
The method for establishing the microscopic model of the catalyst layer comprises the following steps:
s1, performing model assumption and geometric setting on a catalyst layer to obtain a catalyst layer model;
s2, establishing a representative volume unit model of the catalyst layer based on the obtained catalyst layer model;
s3, finite element analysis is carried out on the representative volume unit.
Further, in the catalyst layer model in S1, the catalyst layer includes agglomerates and primary voids between agglomerates.
Further, the aggregate comprises carbon-supported platinum Pt/C particles, secondary gaps arranged among the carbon-supported platinum Pt/C particles, electrolyte arranged among the secondary gaps, and Nafion films coated on the carbon-supported platinum Pt/C particles;
the carbon-supported platinum Pt/C particles are composed of C particles and Pt particles, wherein the C particles and the Pt particles are spherical, and the Pt particles are uniformly supported on the C particles.
Further, the representative volume units are small enough in the macrostructure to be considered a particle, the representative volume units are substantially larger than the characteristic dimensions of the composite material on a microscopic scale, and the microstructure comprised by the representative volume units exhibits the microscopic characteristics of the composite material.
Further, the process of establishing the representative volume unit model of the catalyst layer in S2 includes the following steps:
Setting a matrix phase, a inclusion phase and an interface phase in 3D modeling software;
Setting the inclusion phase as a sphere structure, setting the matrix phase as a cube structure, and setting the interface phase as a shell structure wrapping the matrix phase;
The global geometry options are set to allow the inclusions to contact each other to achieve a larger volume fraction, and periodic boundary conditions are used to obtain model I.
Further, the matrix phase is the entire catalyst layer;
the inclusion phase is carbon-supported platinum Pt/C particles;
the interface phase is an interface between the inclusions, and the interface phase is a Nafion film.
Further, the step S2 also comprises the step of optimizing the model I, which comprises the following steps:
and eliminating a sphere with the diameter being the size of the inclusion phase at the central coordinate of each inclusion phase to obtain a hole, so that a fine aggregate model is further built.
Sequentially generating C particles, pt particles and an outer layer Nafion film at the hole, and subtracting a part which is not in the representative volume unit model by using a Boolean algorithm to finish the establishment of a single aggregate;
and finally, sequentially generating each aggregate to complete the establishment of the representative volume unit model.
Further, the finite element analysis process in S3 includes the steps of:
S301, setting material properties, namely respectively endowing Pt, C, nafion membranes and air materials in the representative volume unit model with the material properties;
S302, establishing a network, dividing grids, and setting a solving domain and boundary conditions;
s303, calculating the model by a computer.
Further, in the S302 process, the mesh division mode is free division, and intelligent mesh division is used for mesh size control;
After endowing unit characteristics to all geometric bodies and setting grid division setting, dividing all grids to obtain a finite element model;
in a finite element model, taking C as a target surface, taking Pt as a contact surface, and establishing contact between the Pt and the C, wherein 6 contacts are generated for each agglomerate;
In the S303 process, acting force with preset magnitude is applied in any direction, a time end point and a time increment are set, and the destructive effect of the acting force on the whole catalytic layer is calculated through finite element analysis by a representative volume unit.
The method for establishing the microscopic model of the catalyst layer is applied to model test of mechanical properties of the catalyst layer, in the established microscopic model of the catalyst layer, acting force with preset magnitude is applied in any direction, and the destructive effect of the acting force on the whole catalyst layer is calculated through finite element analysis by a representative volume unit, so that the mechanical properties of the catalyst layer are obtained.
Compared with the prior art, the invention builds a three-dimensional finite element model of the catalyst layer based on the actual microstructure and mechanical property of the catalyst layer, further researches the influence of different microstructures and actual working conditions on the mechanical property of the catalyst layer, analyzes the rule of improving the performance of the catalyst layer, provides model reference for optimizing the microstructure and mechanical property of the proton exchange membrane fuel cell, and is beneficial to improving the performance of the cell.
The invention can be used for simulation research of the relation between the microstructure and the physical properties of the catalyst layer under different use conditions, such as the rule of influence of the sizes, the distribution and the content of each particle on the parameters of the catalyst layer, such as the elastic modulus, the yield strength, the internal stress distribution, the wet heat cycle damage characteristic, the electrical conductivity, the thermal conductivity and the like, and is beneficial to the optimization and the improvement of the performance of the fuel cell.
Drawings
FIG. 1 is a flow chart of the method of the present invention;
FIG. 2 is a schematic illustration of a catalyst layer agglomerate model;
FIG. 3 is a representative volumetric cell model of different aggregate volume fractions in the present invention;
FIG. 4 is a schematic representation of a geometric model of agglomerate grains according to the present invention;
FIG. 5 is a three-dimensional finite element model internal stress cloud and maximum stress interface stress cloud for an aggregate volume fraction of 0.30 according to the present invention;
FIG. 6 is a three-dimensional finite element model internal stress cloud and maximum stress interface stress cloud for an aggregate volume fraction of 0.35 according to the present invention;
FIG. 7 is a three-dimensional finite element model internal stress cloud and maximum stress interface stress cloud for an aggregate volume fraction of 0.38 according to the present invention.
Detailed Description
The invention will now be described in detail with reference to the drawings and specific examples.
Examples
In fig. 1, the structural design and application of the microscopic model of the catalyst layer in the proton exchange membrane fuel cell comprises the following steps:
s1, model assumption and geometric setting;
s2, establishing a representative volume unit model of the catalyst layer;
s3, finite element analysis is carried out on the representative volume unit model;
In the structural design and application of the microscopic model of the catalyst layer, the modeling target area is a repeating unit of the catalyst layer, the catalyst layer model is based on an aggregate model, the catalyst layer is composed of a plurality of aggregates and primary gaps among the aggregates, the aggregates are composed of catalyst carbon-supported platinum Pt/C, electrolyte and secondary gaps, and a schematic diagram of the aggregate model is shown in figure 2.
In step S1, the model assumption and geometry settings are as follows:
a. the catalyst layer is macroscopically uniform and microscopically periodic;
b. The selected representative volume units are small enough to be considered a particle in the overall macrostructure; the ability to contain sufficient microstructures on a microscopic scale to exhibit the microscopic properties of the composite. Thus the macroscopic properties of the whole catalyst layer can be obtained by performing a simulation analysis of the representative volume units;
c. carbon particles and platinum particles in the agglomerates are spherical, pt particles are small spheres and are adsorbed on carbon particles with larger radius, and the Nafion film is coated on the outer layer of the Pt/C particles, and the thickness of the Nafion film is 10% relative to the whole diameter of the agglomerates, so that the agglomerates are in line with the agglomerate model, and the geometric model is convenient to build.
In step S2, building a representative volume element model (RVE) of the catalyst layer using three-dimensional modeling software comprises the steps of:
S201, establishing an RVE simplified model: the matrix phase, inclusion phase and interface phase are set in the 3D modeling software. Wherein the matrix phase represents the entire catalyst layer, and the matrix is sized as cubes having a side length of 403.55 nm; the inclusion phase represents the Pt/C catalyst, the interfacial phase is the interface between the inclusions, represents the Nafion layer wrapped on the surface of the agglomerate, and the layer is provided as a continuous material.
The inclusion phase was first reduced to a large sphere, externally wrapped with a layer of Nafion membrane having a thickness of 10% relative to the overall diameter of the agglomerate. The specific geometrical parameters of the inclusion phases are set forth in table 1. For the interfacial phase, only the relative thickness thereof was set to 0.1 and had a constant aspect ratio.
TABLE 1 microstructure parameter settings for inclusion phases
The global geometry options were set prior to RVE generation, allowing the agglomerates to contact each other to achieve a greater volume fraction, and using periodic boundary conditions, the specific relevant settings are shown in table 2. At this time, a simplified model I of RVE was obtained, and then the PEMFC catalyst layer RVE simplified model with different aggregate volume fractions was obtained by taking volume fraction values of 0.3 and 0.35 and keeping the other parameters the same as those in Table 1, as shown in FIG. 3. In the figure, the red part represents the catalyst, the blue part represents the Nafion film, the red plus blue part is an agglomerate, and the rest transparent part is a gap, namely the part of the catalyst layer matrix which is not occupied by the agglomerate.
Global geometry option settings of Table 2 RVE
S202, optimizing an RVE simplified model: the model was optimized on the model I basis, and the specific operations were as follows: the elimination of a sphere of diameter the size of the inclusion phase at the center coordinates of each inclusion phase facilitates the further creation of a fine-scale agglomerate model. C particles, pt particles and outer Nafion are sequentially generated at the hole, then a Boolean algorithm is used for subtracting the part which is not in the RVE model, and the establishment of a single aggregate is completed, as shown in figure 4, the small spheres are Pt particles (6 in number), the big spheres are carbon particles, and the shell layer of the outermost layer is Nafion. And finally, sequentially generating each aggregate to complete the model establishment. The size data of the agglomerates are shown in table 3.
TABLE 3 agglomeration size data
In step S3, a finite element analysis is performed on the representative volumetric cell model, comprising the steps of:
S301, setting material properties: the four materials in the RVE model were each given material properties, see table 4 in detail.
Table 4 RVE Material Properties of the model
S302, establishing a network, dividing grids, and setting a solving domain and boundary conditions: the geometric body to be set is selected and given its unit attribute. The grid division mode is free division, and intelligent grid division is used for controlling the grid size; the cell shape is controlled to be a 3D tetrahedron. After endowing unit characteristics to all geometric bodies and setting grid division setting, dividing all grids to obtain a finite element model. Then, with C as the target surface and Pt as the contact surface, contact between Pt and C is established, and 6 contacts are generated for each agglomerate.
In this embodiment, static analysis is performed on the established finite element model, and stretching in the Y-axis direction is performed. The relevant settings are to be made before solving: firstly, fixing an XZ plane (lower surface); then applying pressure to the upper surface of the XZ, wherein the pressure is 10Mpa; and finally setting the time end point as 10, setting the time increment as 0.5, and executing the solving. And after solving, displaying a solving result by using a post-processing module.
Three-dimensional internal stress cloud charts of three different aggregate volume fraction models are respectively shown in fig. 5, 6 and 7, and in order to more finely observe the internal stress strain condition and structural change of the aggregates, the aggregates with the largest stress appear are selected as the centers, and an XY working surface is established as the cross section to display the stress change of the internal structure, and the stress change is also shown in fig. 5, 6 and 7.
Analysis of the stress cloud shows that the catalyst layer is internally stressed under the action of an external load, and larger internal stress is generated near the agglomerates under the influence of the internal structure, and the maximum stress occurs around the agglomerates, particularly in a direction perpendicular to the external force. Meanwhile, the agglomerates can move away from the original positions to form new holes; the inside of the agglomerate is subjected to small stress of the carbon-supported platinum catalyst, the positions of Pt particles can change to a certain extent relative to the central position of the whole agglomerate, the agglomeration phenomenon of the Pt particles can be possibly caused, and massive Pt clusters are formed, so that the area of a three-phase active area in the agglomerate, which can undergo electrochemical reaction, is reduced. Cracks and agglomeration of Pt particles both produced under external forces can degrade the performance of the fuel cell, resulting in a cycle life that does not meet commercial standards.
The internal stress cloud patterns of three different volume fraction models are compared and analyzed, and as the volume fraction of the aggregate increases, the stress strain inside the catalyst layer increases under the same external pressure. The maximum stress value corresponding to the volume fraction of 0.3 is 20.2956Mpa, and the maximum stress value corresponding to the volume fraction of 0.38 is 25.6655Mpa, and the maximum stress is perpendicular to the pressure direction near the agglomerate. From the RVE model finite element analysis of a volume fraction of 0.38, it was found that the smaller the agglomerate particles, the greater the stress developed in the vicinity thereof, and correspondingly the greater the destructive effect on the whole catalytic layer.
In summary, the model established by the method of the invention can reflect the deformation behavior of the internal microstructure of the PEMFC catalyst layer under the action of external force, provides model reference for researching the damage mechanism and performance improvement of the catalyst layer, provides model reference of microstructure and mechanical property for materials which are difficult to analyze by an experimental method of the proton exchange membrane fuel cell, saves experimental resources, provides convenience for research, and reduces research cost.
The technical scheme can also be used for simulation research on the relation between the microstructure and the physical properties of the catalyst layer under different use conditions, such as the rule of influence of the sizes, the distribution and the content of each particle on the parameters of the elastic modulus, the yield strength, the internal stress distribution, the wet heat cycle damage characteristic, the electrical conductivity, the thermal conductivity and the like of the catalyst layer, and is beneficial to the optimization and the improvement of the performance of the fuel cell.
The previous description of the embodiments is provided to facilitate a person of ordinary skill in the art in order to make and use the present invention. It will be apparent to those skilled in the art that various modifications can be readily made to these embodiments and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above-described embodiments, and those skilled in the art, based on the present disclosure, should make improvements and modifications without departing from the scope of the present invention.
Claims (6)
1. A method for creating a microscopic model of a catalyst layer, comprising the steps of:
s1, performing model assumption and geometric setting on a catalyst layer to obtain a catalyst layer model;
s2, establishing a representative volume unit model of the catalyst layer based on the obtained catalyst layer model;
S3, carrying out finite element analysis on the representative volume unit;
s1: model assumptions and geometry settings were as follows: a. the catalyst layer is macroscopically uniform and microscopically periodic; b. the selected representative volume units are small enough to be considered a particle in the overall macrostructure; the microstructure capable of being contained in a sufficient quantity on a microscopic scale shows microscopic characteristics of the composite material; c. the carbon particles and the platinum particles in the agglomerate are spherical, the Pt particles are small spheres and are adsorbed on the carbon particles with larger radius, and the Nafion film is coated on the outer layer of the Pt/C particles, and the thickness of the Nafion film is 10% relative to the whole diameter of the agglomerate;
the process of establishing the representative volume unit model of the catalyst layer in S2 includes the following steps:
Setting a matrix phase, a inclusion phase and an interface phase in 3D modeling software;
Setting the inclusion phase as a sphere structure, setting the matrix phase as a cube structure, and setting the interface phase as a shell structure wrapping the matrix phase;
Setting global geometric options, allowing the objects to be in contact with each other to achieve a larger volume fraction, and adopting a periodic boundary condition to obtain a model I;
the matrix phase is the whole catalyst layer;
the inclusion phase is carbon-supported platinum Pt/C particles;
The interface phase is an interface between the inclusions, and the interface phase is a Nafion film;
s2, optimizing the model I, comprising the following steps:
subtracting a sphere with the diameter being the size of the inclusion phase from the central coordinate of each inclusion phase to obtain a hole;
Sequentially generating C particles, pt particles and an outer layer Nafion film at the hole, and subtracting a part which is not in the representative volume unit model by using a Boolean algorithm to finish the establishment of a single aggregate;
Finally, generating each aggregate in turn, and thus completing the establishment of the representative volume unit model;
The finite element analysis process in S3 includes the steps of:
S301, setting material properties, namely respectively endowing Pt, C, nafion membranes and air materials in the representative volume unit model with the material properties;
S302, establishing a network, dividing grids, and setting a solving domain and boundary conditions;
s303, calculating the model by a computer.
2. The method for creating a microscopic model of a catalyst layer according to claim 1, wherein in the model of a catalyst layer in S1, the catalyst layer includes agglomerates and primary voids between agglomerates.
3. The method for creating a microscopic model of a catalyst layer according to claim 2, wherein the agglomerates comprise carbon-supported platinum Pt/C particles, secondary gaps provided between the carbon-supported platinum Pt/C particles, an electrolyte provided between the secondary gaps, and Nafion membranes coated on the carbon-supported platinum Pt/C particles;
the carbon-supported platinum Pt/C particles are composed of C particles and Pt particles, wherein the C particles and the Pt particles are spherical, and the Pt particles are uniformly supported on the C particles.
4. A method of creating a microscopic model of a catalyst layer according to claim 1, wherein the representative volume element is considered a particle in a macroscopic structure, the representative volume element being substantially larger in microscopic dimension than the characteristic dimension of the composite material, the microscopic structure comprised by the representative volume element exhibiting microscopic properties of the composite material.
5. The method for building a microscopic model of a catalyst layer according to claim 1, wherein in the step S302, the mesh division is performed in a free manner, and the mesh size control uses intelligent mesh division;
After endowing unit characteristics to all geometric bodies and setting grid division setting, dividing all grids to obtain a finite element model;
in a finite element model, taking C as a target surface, taking Pt as a contact surface, and establishing contact between the Pt and the C, wherein 6 contacts are generated for each agglomerate;
In the S303 process, acting force with preset magnitude is applied in any direction, a time end point and a time increment are set, and the destructive effect of the acting force on the whole catalytic layer is calculated through finite element analysis by a representative volume unit.
6. The method is characterized in that in a microscopic model of the catalyst layer established in any one of claims 1 to 5, a force with a preset magnitude is applied in any direction, and a damage effect of the force on the whole catalyst layer is calculated through finite element analysis by a representative volume unit, so that the mechanical property of the catalyst layer is obtained.
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| US11894566B2 (en) | 2020-05-12 | 2024-02-06 | Robert Bosch Gmbh | Catalyst materials for a fuel cell stack |
| CN112632786B (en) * | 2020-12-25 | 2021-09-07 | 清华大学 | Method and system for generating random structure of fuel cell catalyst layer and computer equipment |
| CN112786901B (en) * | 2021-03-02 | 2022-06-28 | 上海交通大学 | Preparation method of fuel cell membrane electrode with controllable surface buckling |
| CN113506895B (en) * | 2021-06-18 | 2022-07-15 | 西安交通大学 | Fuel cell catalyst layer performance analysis method based on relative humidity influence |
| CN113506880B (en) * | 2021-07-12 | 2022-04-29 | 清华大学 | Method, system, apparatus and medium for generating microstructure of fuel cell catalyst layer |
| CN114023400B (en) * | 2021-10-19 | 2024-08-20 | 上海索辰信息科技股份有限公司 | Method for rapidly predicting equivalent characteristics of composite materials under different volume fractions |
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| CN106815408A (en) * | 2016-12-23 | 2017-06-09 | 上海交通大学 | Long fiber composites random structure is generated and its elastic performance Forecasting Methodology |
| WO2020056405A1 (en) * | 2018-09-14 | 2020-03-19 | Northwestern University | Data-driven representation and clustering discretization method and system for design optimization and/or performance prediction of material systems and applications of same |
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| CN106815408A (en) * | 2016-12-23 | 2017-06-09 | 上海交通大学 | Long fiber composites random structure is generated and its elastic performance Forecasting Methodology |
| WO2020056405A1 (en) * | 2018-09-14 | 2020-03-19 | Northwestern University | Data-driven representation and clustering discretization method and system for design optimization and/or performance prediction of material systems and applications of same |
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| 微观缩松对蠕铁微观组织和力学性能的影响;刘金祥;张庆;左正兴;熊毅;赵丽丽;;北京理工大学学报(第08期);全文 * |
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