Numerical simulation of mass transfer and convection near a hydrogen bubble during water electrolysis in magnetic fields

Hydrogen produced from wind or solar power could be used easily for storing energy also at large scale, thus allowing to bridge the gap between supply and demand of renewable energy with respect to time and place. When splitting water by electrolysis, a deeper look at local phenomena near single bubbles at the electrode might be helpful to improve our understanding of the process. In the recent literature, magnetic fields are discussed with respect to the bubble departure, thereby possibly influencing the efficiency of the process [1-7].
The contribution will present numerical simulations resolving in detail local phenomena near a single hydrogen bubble at the cathode during the electrolysis of water in external magnetic fields. The modeling is supported by data of recent experiments on hydrogen single bubbles evolving at a platinum micro-electrode [7-9]. The results will provide insight into the local and temporal behavior of electrolyte convection, species concentration and mass transfer during electrolysis. Furthermore, the influence of the Lorentz force caused by vertical and horizontal magnetic fields on the departure will be discussed in detail (see Figs. 1 and 2).

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