Hydrogen-fueled fuel cells are considered one of the key strategies to tackle the achievement of fully-sustainable mobility. The transportation sector is paying significant attention to the development and industrialization of proton exchange membrane fuel cells (PEMFC) to be introduced alongside batteries, reaching the goal of complete de-carbonization. In this paper a multi-phase, multi-component, and non-isothermal 3D-CFD model is presented to simulate the fluid, heat, and charge transport processes developing inside a hydrogen/air PEMFC with a serpentine-type gas distributor. Model results are compared against experimental data in terms of polarization and power density curves, including an improved formulation of exchange current density at the cathode catalyst layer, improving the simulation results’ accuracy in the activation-dominated region. Then, 3D-CFD fields of reactants’ delivery to the active electrochemical surface, reaction rates, temperature distributions, and liquid water formation are analyzed, and critical aspects of the current design are commented, i.e., the inhomogeneous use of the active surface for reactions, limiting the produced current and inducing gradients in thermal and reaction rate distribution. The study shows how a complete multi-dimensional framework for physical and chemical processes of PEMFC can be used to understand limiting processes and to guide future development.

The growing energy demand is inevitably accompanied by a strong increase in greenhouse gas emissions, primarily carbon dioxide. The adoption of new energy vectors is therefore seen as the most promising countermeasure. In this context, hydrogen is an extremely interesting energy carrier, since it can be used as a fuel in both conventional energy systems (internal combustion engines, turbines) and in Fuel Cells (FC). In particular, PEM (Polymeric Electrolyte Membrane) FC are given growing attention in the transportation sector as a Life-Cycle viable solution to sustainable mobility.The use of 3D CFD analysis of for the development of efficient FC architectures is extremely interesting since it can provide a fast development tool for design exploration and optimization. The designer can therefore take advantage of a robust and accurate modelling in order to define and develop fuel cell systems in a more time-efficient and cost-efficient way, to optimize their performance and to lower their production costs.So far, studies available in the scientific literature lack of quantitative validation of the CFD simulations of complete PEM fuel cells against experimental evidence. The proposed study presents a quantitative validation of a multi-physics model of a Clearpak PEM cell. The chemistry and physics implemented in the methodology allow the authors to obtain both thermal and electrical results, characterizing the performance of each component of the PEM.The results obtained, compared with the experimental polarization curve, show that the model is not only numerically stable and robust in terms of boundary conditions, but also capable to accurately characterize the performance of the PEM cell over almost its entire polarization range.

Hydrogen is one of the most promising energy vectors for achieving the decarbonization of the propulsion systems market. Polymer Electrolyte Membrane Fuel Cell system (PEMFCs) stand out in this panorama, thanks to reduced activation times and low temperatures of use, easily adapting to the needs of the sector. In this paper, a multi-phase, multi-component and non-isothermal 3D-CFD model is proposed to simulate the effects of PEMFC ageing, limiting the system durability due to slow membrane corrosion and loss of material performance and properties degradation, resulting in a reduced current density under equal voltage. The model is applied both in 1D and 3D frameworks implementing a validated model from literature, allowing to estimate the useful life of the cell as a function of parameters such as the degradation rate and the crossover rate. Simulations are carried out at different membrane thicknesses and for different membrane conductivities, using a hydrogen-fuelled serpentine-type PEM fuel cell. The study relevance lies in the possibility to investigate the critical aspects limiting PEMFC system durability, as well as the optimal conditions of use, and it allows to identify corrective design actions.