CN-121997618-A - Method and device for evaluating structure of electrolytic cell polar plate, storage medium and electronic equipment

CN121997618ACN 121997618 ACN121997618 ACN 121997618ACN-121997618-A

Abstract

The invention relates to a method, a device, a storage medium and electronic equipment for evaluating an electrolytic tank polar plate structure, wherein the method comprises the steps of constructing a multi-physical-field model based on an alkaline electrolytic tank and carrying out finite element grid division to obtain the multi-physical-field finite element model, setting the multi-physical-field finite element model when carrying out bubble volume distribution calculation in a small chamber by utilizing the multi-physical-field finite element model, enabling bubbles to be equivalent to particles, adopting homogeneous flow and neglecting radial speed in running speed, setting a single-phase flow model equation for describing electrolyte flow by utilizing single-phase flow in each finite element grid in the multi-physical-field finite element model based on the bubbles to be equivalent to the particles and adopting the homogeneous flow, and carrying out convection-diffusion equation for describing bubble movement by utilizing convection-diffusion, carrying out step iteration operation on the multi-physical-field finite element model to obtain a multi-physical-field distribution result of an electrolytic tank polar plate to be evaluated, and evaluating the structure of the electrolytic tank polar plate to be evaluated based on the multi-physical-field distribution result. The structural design evaluation efficiency can be improved.

Inventors

Huang Danji
HUANG PENGHUI
ZHOU WEI
Min Luofu
CHEN MING

Assignees

中石油深圳新能源研究院有限公司
中国石油天然气股份有限公司

Dates

Publication Date: 20260508
Application Date: 20241101

Claims (10)

1. A method of evaluating the structure of an electrolytic cell plate, comprising: constructing a multi-physical field model based on an alkaline electrolytic cell comprising an electrolytic cell polar plate to be evaluated, and carrying out finite element mesh division on the multi-physical field model to obtain a multi-physical field finite element model; based on statistics of the diameters of bubbles generated in the electrolysis process of the industrial alkaline electrolytic tank, the bubbles are equivalent to particles when the volume distribution calculation of the bubbles in the cell is carried out by utilizing the multi-physical-field finite element model; Based on the characteristic that the industrial alkaline electrolytic tank adopts an alkaline pump to carry out forced convection on electrolyte and gas movement is influenced by alkaline liquid flow, the industrial alkaline electrolytic tank is arranged in the multi-physical-field finite element model and adopts homogeneous flow; Based on the running speed of bubbles generated in the industrial alkaline electrolytic tank electrolytic process on the surface of an electrolytic tank polar plate, the radial speed in the running speed is ignored in the multi-physical field finite element model; Setting a single-phase flow model equation for describing the flow of electrolyte by utilizing single-phase flow and a convection-diffusion equation for describing the movement of bubbles by utilizing convection-diffusion based on the equivalence of bubbles as particles and the adoption of homogeneous flow for each finite element grid in the multi-physical field finite element model; and carrying out step-by-step iterative operation on the multi-physical-field finite element model, obtaining a multi-physical-field distribution result of the to-be-evaluated electrolytic tank polar plate, and evaluating the structure of the to-be-evaluated electrolytic tank polar plate based on the multi-physical-field distribution result.
2. The method of evaluating an electrolytic cell plate structure of claim 1, wherein the step-and-repeat operation of the multi-physical field finite element model to obtain a multi-physical field distribution result of the electrolytic cell plate to be evaluated comprises: performing step-by-step iterative operation on the basis of a single-phase flow model equation and a flow-diffusion equation in the multi-physical-field finite element model to obtain bubble volume fraction distribution and liquid velocity distribution; Calculating current density distribution based on the electrode plate voltage of the electrolytic cell, the lowest voltage of electrolytic reaction, the current of the catalytic electrode and a single-phase current model equation; and calculating the temperature field distribution based on a single-phase flow model equation, a convection-diffusion equation, constant-pressure heat capacity of the electrolyte, heat conductivity coefficient of the electrolyte and heat source quantity.
3. A method of evaluating an electrolyzer plate structure in accordance with claim 2, wherein the single phase flow model equation is as follows: Where u l is the electrolyte velocity, ρ l is the liquid density, φ l is the liquid phase volume fraction, p is the pressure, K is the viscous stress tensor, K m is the diffusion stress, g is the gravitational acceleration, and the convection-diffusion equation is as follows: Where ρ g ＝1-ρ l is the bubble volume fraction, D eff is the equivalent diffusion coefficient of the gas, and R' represents the effect of the bubble generation rate on the bubble volume fraction.
4. A method of evaluating an electrolyzer plate structure in accordance with claim 3, wherein the calculating a current density profile based on electrolyzer plate voltage, lowest voltage at which electrolysis reactions occur, current at the catalytic electrode, single phase flow model equations comprises: Under the given voltage of the electrolytic cell polar plate, acquiring equivalent exchange current density of the catalytic electrode based on the current of the cathode catalytic electrode and the volume fraction of bubbles acquired by a single-phase flow model equation; Constructing a first function of current density distribution based on the reaction current of the cathode catalytic electrode, the contact resistance between the cathode plate and the cathode catalytic electrode, the resistance of the cathode plate, the resistance of the diaphragm and the ohmic overpotential; Constructing a second function of current density distribution based on the cell plate voltage, the lowest voltage at which the electrolytic reaction occurs, the ohmic overpotential, and the polarization overpotential of the cathodic electrochemical reaction; constructing a third function of current density distribution based on equivalent exchange current density of the cathode catalytic electrode, transfer coefficient of the cathode electrode plate, number of electrons transferred in the electrolytic reaction, polarization overpotential of the electrochemical reaction of the cathode electrode plate, electrolyte temperature and reaction current of the cathode catalytic electrode; and acquiring the current density distribution based on the first function, the second function and the third function of the current density distribution.
5. The method of evaluating an electrolyzer plate structure of claim 4 wherein the second function of current density distribution is as follows: the first function of the current density profile is as follows: η ohm ＝i(r c +r p +r d ) The third function of the current density profile is as follows: Wherein E cell is the electrode plate voltage of the electrolytic cell, Is the lowest voltage at which the electrolytic reaction occurs, η phm is the ohmic overpotential, η A and η c are the polarization overpotential of the cathodic and anodic electrochemical reactions, respectively, Δg is the gibbs free energy change value, z is the number of electrons transferred in the electrolytic reaction, F is the faraday constant, i is the current density, R c is the contact resistance between the bipolar plate and the catalytic electrode, R p is the resistance of the electrode, R d is the resistance of the diaphragm, i eA 、i eC is the equivalent exchange current density of the cathodic catalytic electrode and the anodic catalytic electrode, α A is the transfer coefficient of the cathodic plate, T is the electrolyte temperature, and R is the ideal gas constant.
6. The method of evaluating an electrolyzer plate structure of claim 4 wherein the obtaining a current density profile based on the first, second, and third current density profile functions comprises: Obtaining boundary heat sources based on electrode potential, liquid phase volume fraction, equilibrium potential of electrolytic reaction, local reaction current density and temperature of electrolyte; acquiring ohmic heat generation density in the cell based on the reaction current of the electrode, the electrode potential, the reaction current of the electrolyte, the electrode potential and the electrode liquid potential; acquiring the heat source amount provided by the electrolysis reaction based on the boundary heat source and the ohmic heat generation density; the temperature field distribution is obtained based on the liquid density, the constant pressure heat capacity of the electrolyte, the liquid speed, the heat conductivity of the electrolyte and the heat source provided by the electrolysis reaction.
7. The method of evaluating the structure of an electrolytic cell plate according to any one of claims 1 to 6, wherein the evaluating the structure of the electrolytic cell plate to be evaluated based on the multi-physical field distribution result comprises: Respectively obtaining the highest bubble volume fraction value, the highest current density value and the highest temperature in a set area according to the bubble volume fraction distribution, the current density distribution and the temperature field distribution in the multi-physical field distribution result; if the highest bubble volume fraction value is higher than a preset bubble volume fraction threshold, or the highest current density value is higher than a preset current density threshold, or the temperature difference between the highest temperature and the liquid inlet temperature is higher than a preset temperature difference threshold, determining that the structure evaluation result of the to-be-evaluated electrolytic cell polar plate is unqualified.
8. An apparatus for evaluating the structure of an electrolytic cell plate, the apparatus comprising: The finite element model construction module is used for constructing a multi-physical field model based on an alkaline electrolytic tank comprising an electrolytic tank polar plate to be evaluated, and carrying out finite element mesh division on the multi-physical field model to obtain a multi-physical field finite element model; The first simplifying module is used for setting bubbles to be equivalent to particles when the volume distribution calculation of the bubbles in the cell is carried out by utilizing the multi-physical field finite element model based on the statistics of the diameters of the bubbles generated in the electrolysis process of the industrial alkaline electrolytic cell; the second simplifying module is used for carrying out forced convection on electrolyte by adopting an alkaline pump based on the characteristic that the industrial alkaline electrolytic tank is influenced by alkaline liquid flow and gas movement is arranged in the multi-physical-field finite element model by adopting homogeneous flow; a third simplification module, which is used for neglecting the radial speed in the operation speed in the multi-physical field finite element model based on the operation speed of bubbles generated in the electrolysis process of the industrial alkaline electrolytic tank on the surface of the electrolytic tank polar plate; The model parameter setting module is used for setting a single-phase flow model equation for describing the flow of electrolyte by utilizing single-phase flow and a convection-diffusion equation for describing the movement of bubbles by utilizing convection-diffusion based on the fact that bubbles are equivalent to particles and homogeneous flow is adopted; The structural design evaluation module is used for carrying out step-by-step iterative operation on the multi-physical-field finite element model, obtaining a multi-physical-field distribution result of the electrolytic tank plate to be evaluated, and evaluating the structure of the electrolytic tank plate to be evaluated based on the multi-physical-field distribution result.
9. A storage medium having stored thereon a program or instructions which when executed by a processor perform the steps of the method of assessing a plate structure of an electrolysis cell according to any one of claims 1 to 7.
10. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the steps of the method of evaluating the plate structure of an electrolytic cell according to any one of claims 1 to 7 when the program is executed by the processor.

Description

Method and device for evaluating structure of electrolytic cell polar plate, storage medium and electronic equipment Technical Field The present invention relates to the field of structural design technologies, and in particular, to a method and an apparatus for evaluating a structure of an electrolytic cell plate, a storage medium, and an electronic device. Background The alkaline electrolytic tank is formed by serially connecting a plurality of cells, and electrolyte is placed in the cells, wherein each cell comprises a cathode polar plate, a cathode catalytic electrode, a diaphragm, an insulating gasket, an anode catalytic electrode and an anode polar plate. In the electrolysis of electrolytes in cells, there are more complex multi-physical process couplings including, but not limited to, electrochemical processes, thermodynamic processes, gas-liquid two-phase flow processes, and ion mass transfer processes and their couplings. In the related art, electrode plates (abbreviated as electrolytic cell electrode plates) in industrial alkaline electrolytic cells, such as cathode electrode plates and anode electrode plates, often adopt mastoid structures to enhance the uniformity of the flow of electrolyte in the cell interior, thereby improving the electrolytic efficiency. When the structural design of the electrolytic tank polar plate is unreasonable, the situation of bubble accumulation in the small chamber can occur, thereby affecting the temperature distribution and the reaction current of the electrolyte in the small chamber and further affecting the hydrogen production rate, the energy efficiency and the product purity of the electrolytic tank. Thus, after the cell plate structure is designed, the designed cell plate needs to be evaluated. In order to evaluate whether the structural design of the electrode plates in the alkaline electrolytic cell is reasonable, an experimental method or a simulation method is generally required to verify the structure of the electrode plates. The experimental method comprises the steps of manufacturing and assembling a designed polar plate structure, constructing an alkaline electrolytic tank experimental platform, verifying safety and performance, and evaluating the polar plate structure design based on the verification result of safety and performance. However, the experimental method has long period and high cost. For example, for a 1000 standard industrial electro-hydrogen plant, the processing cost of the electrode plate can be as high as about millions of yuan, and experiments also need to be conducted with electricity costs of at least hundreds of thousands of yuan. In addition, when the structural design of the polar plate is unreasonable, the experimental scheme also has certain danger. Therefore, by adopting an experimental method, the design requirement of the polar plate structure for rapid iteration cannot be met. In order to meet the design requirement of a rapid iterative polar plate structure, a multi-physical field simulation technology is utilized to construct a multi-physical field model based on an electrolytic tank polar plate, and a finite element method is utilized to verify the polar plate structure design scheme based on the multi-physical field distribution result by solving the multi-physical field distribution result comprising current distribution, temperature distribution and bubble volume fraction distribution on the electrolytic tank polar plate in the multi-physical field model. However, the method can effectively reduce the test period and cost of the structural design of the electrolytic tank polar plate, and can obtain the physical field distribution condition of the electrolytic tank polar plate in the small chamber by adopting a multi-physical field simulation technology, but because of the complex structure of the surface of the electrolytic tank polar plate, complex multi-physical process coupling exists in the finite element solving process, particularly gas-liquid two-phase flow and coupling thereof, so that the multi-physical field model has poor convergence in the solving process, slow convergence speed and lower structural evaluation efficiency, and cannot meet the performance verification requirement of the polar plate with the complex structure. Disclosure of Invention In view of this, the present invention provides a method, apparatus, storage medium and electronic device for evaluating the structure of an electrolytic cell plate. Specifically, the invention is realized by the following technical scheme: According to a first aspect of the present invention there is provided a method of assessing the structure of an electrolytic cell plate, the method of assessing the structure of an electrolytic cell plate comprising: constructing a multi-physical field model based on an alkaline electrolytic cell comprising an electrolytic cell polar plate to be evaluated, and carrying out finite element mesh division on the multi-physical