Coupled simulation approaches for PEM fuel cells by OpenFOAM

Abstract

Proton exchange membrane (PEM) fuel cells are known as environmental friendly energy conservation devices, and have the potential to be suitable alternative power sources. The cost and durability of a PEM fuel cell are strongly affected by the involved transport phenomena and reactions, which are two major challenges to be overcome before commercialization. Modeling and simulation are crucial for the cell design and operation. Various “add-on” fuel cell modules are available in commonly-used commercial CFD codes: FLUENT, STAR-CD and COMSOL Multiphysics. However, the length scale of PEM fuel cell’s main components ranges from the micro over the meso to the macro level. The various transport processes at different scales sometimes cannot be captured simultaneously by these codes. On the other hand, physical properties of functional layers used in MEA (membrane electrolyte assembly, consisting of catalyst layers, gas diffusion layers and membrane) play an important role for the cell performance. Therefore coupling of the multi-scale structural and transport characteristics in the functional layers might be an effective way to understand the electrochemical reactions and transient transport phenomena in PEM fuel cells. OpenFOAM (Open Field Operation and Manipulation) is an open source finite volume code having an object-oriented design written in C++, which allows implementation of own models and numerical algorithms. Furthermore, it is possible to integrate other models, e.g., particle-based models, with the OpenFOAM CFD Toolbox. Thus OpenFOAM has the potential to meet the requirements faced in PEM fuel cell simulations as mentioned above. In this paper, various models and applications of OpenFOAM are outlined and reviewed, focusing on the multi-phase transport processes and reactions in PEM fuel cells. The potential methods and challenges coupling OpenFOAM with other modeling techniques are also discussed and highlighted