2D dimensionless numbers in isothermal fuel cells with smooth electrocatalysts. (14th December 2022)

• Record Type: Journal Article
• Authors: Zinola, C.F.
• Is Part Of: Chemical engineering science. Volume 263(2022)
• Publication Date: 2022-12-14
• Subjects: Dimensionless numbers -- Polarization curves -- Fuel cells -- Current distribution -- Overpotential profile; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2022.118056
• Languages: English
• ISSNs: 0009-2509

Abstract

Graphical abstract: Highlights: An electrochemical Damkoehler number was defined as the ratio of the operational current and its limiting value. Exact analytical functions for distribution of current densities were derived for smooth anode and cathodes in 2D PEM fuel cells. A dimensionless equation was derived for the 2D PEM fuel cell using Wagner, Damkoehler and Graetz numbers. Abstract: One of the problems in the optimization of a fuel cell performance is the operation prediction for short and long-time behaviours. The employ of exact analytical functions for picturing the distribution of potential and current densities in 2D polymer electrolyte membrane fuel cells, generalizes the study and reduces large computational times for each experimental situation. Therefore, we foresee analytical solutions for mass balance equations using the asymptotic velocity equations (normal and tangential coordinates) to obtain a 2D concentration, current and overpotential profiles for smooth platinum catalysts. Dimensionless numbers are deduced, i.e. Wagner, Damkoehler and Graetz to characterize the fuel cell performance, first with a 1D approach and also along 2D coordinates. Besides, the complete polarization curve is predicted comparing the theoretical results with the proper variations of electrochemical magnitudes in a single home-made hydrogen/oxygen 200 cm 2 polymer electrolyte membrane fuel cell.