(358c) Modeling Challenges in the Analysis of Proton Exchange Membrane Water Electrolysis System

Yuanxing Liu,^1,2,3, Sahithi Srijana Akundi^1,2,3, Austin Braniff⁴, Beatriz Dantas⁴, Shayan S. Niknezhad¹, Faisal Khan^{2,3 *}, Yuhe Tian⁴, Efstratios N. Pistikopoulos^1,3*

¹Texas A&M Energy Institute, Texas A&M University, College Station, TX, USA

²Mary Kay O’Connor Process Safety Center (MKOPSC), Texas A&M University, College Station, TX, USA

³Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA

⁴Department of Chemical and Biomedical Engineering, West Virginia University, Morgantown, WV, USA

*Presenter E-mail: liuyuanxing@tamu.edu

Correspondence: fikhan@tamu.edu and stratos@tamu.edu

2024 AIChE Annual Meeting

October 27-31, 2024, San Diego, CA

Abstract

Proton exchange membrane water electrolysis (PEMWE) is a promising technique for the production of green hydrogen. Its exceptional performance can be attained by optimizing the geometry, materials, and operating conditions. Modeling is an effective method for predicting the performance of the cell and assessing the impacts of design and operating variables. However, there exists a discrepancy between the findings of previous studies and experimental observations in regard to the dislocation of hydrogen and oxygen evolution, as indicated by the simulation results obtained using ANSYS Fluent. This appears to be the result of the built-in electrolysis module, which mixed up the terms of exchange current densities as shown in the Scheme 1. This study presents the observation, verification, and correction of the discrepancy. Initially, the default electrolysis module was utilized to develop a CFD-based electrolysis model using ANSYS Fluent. The outcome of this model aligns with existing literature, which confirms that hydrogen is produced at the anode. A Multiphysics model of PEMWE was then developed using COMSOL to investigate the flow and electric fields. The simulation results of the COMSOL model indicate that hydrogen was produced and discharged at the cathode, which is in line with the experimental findings. The study highlights the importance of exercising caution when developing electrolysis models using the built-in module of CFD tools. Careful validation of the model against experimental data is of utmost importance to ensure its reliability and usability in practical applications.

Keywords: Proton exchange membrane water electrolysis; ANSYS Fluent; COMSOL; Simulation; Exchange current density; Hydrogen production; Hydrogen safety