基于欧拉-欧拉方法的CO₂电解池水气传输特性

朱姗¹，黄杰¹，马凤翔¹，赵跃¹，刘伟¹，周涛涛^2*

1.国网安徽省电力科学研究院，安徽 合肥  230601；2.合肥工业大学汽车与交通工程学院，安徽 合肥  230009

摘要：为研究CO₂电解还原过程中的水-气传输特性，基于欧拉-欧拉方法，建立CO₂电解池中多相传质过程与电化学相耦合的计算模型，搭建CO₂电解池试验测试平台，基于试验数据对仿真模型进行验证；在此基础上分别基于单通道模型和大尺寸单蛇形流场模型对电解池工作特性进行模拟分析。仿真结果表明：较大的水流速度可以加快生成气体的排出，利于催化层电化学反应进行；在大尺寸流场中，由于水排出不及时，有相当一部分水通过质子交换膜传递到阴极侧，导致阴极发生水淹，降低阴极侧液态水含量可在一定程度上改善阴极侧的气体传输；为避免阴极水量过多，应合理设计流场结构和供水供气策略。

关键词：CO₂；电解池；试验；数值模拟；单通道模型；单蛇形流场模型

The characteristic and performance of CO₂electrolyzer via Eular-Eular method

ZHU Shan¹, HUANG Jie¹, MA Fengxiang¹, ZHAO Yue¹, LIU Wei¹, ZHOU Taotao^2*

1.State Grid Anhui Electric Power Research Institute, Hefei 230601, China;

2.School of Automotive and Transportation Engineering, Hefei University of Technology, Hefei 230009, China

Abstract：In order to study the characteristics of water-gas transport during the electrolytic reduction of carbon dioxide, a computational model for the coupling of multiphase mass transfer process and electrochemistry in a carbon dioxide electrolytic cell is developed based on the Euler-Euler method. The carbon dioxide electrolytic cell is set up as the experimental test platform, and the numerical model is verified based on the experimental data. On this basis, the working characteristics of the electrolytic cell are simulated and analyzed based on the single channel model and the large size single snake flow field model. It is found that the faster water flow speed can accelerate the discharge of the generated gas, which is conducive to the reaction. In the large-size flow field, due to the water not being discharged in time, a considerable amount of water is transferred to the cathode side through the proton exchange membrane, resulting in the occurrence of cathode flooding. The reduction of liquid water content on the cathode side can improve the gas transmission condition on the cathode side to a certain extent. Therefore, it is necessary to reasonably design the flow field structure and the water supply and gas supply strategy to avoid excessive water in the cathode.

Keywords: CO₂; electrolytic cell; experiment; numerical simulation; single channel model; single snake flow field model