UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Ex-situ characterisation of water droplet dynamics on the surface of a fuel cell gas diffusion layer through wettability analysis and thermal characterisation

Obeisun, OA; Finegan, DP; Engebretsen, E; Robinson, JB; Taiwo, OO; Hinds, G; Shearing, PR; (2017) Ex-situ characterisation of water droplet dynamics on the surface of a fuel cell gas diffusion layer through wettability analysis and thermal characterisation. International Journal of Hydrogen Energy , 42 (7) pp. 4404-4414. 10.1016/j.ijhydene.2017.01.003. Green open access

[thumbnail of Robinson_Ex-situ characterisation of water droplet dynamics on the surface of a fuel cell gas diffusion layer through wettability analysis and thermal characteris_AAM.pdf]
Preview
Text
Robinson_Ex-situ characterisation of water droplet dynamics on the surface of a fuel cell gas diffusion layer through wettability analysis and thermal characteris_AAM.pdf - Accepted Version

Download (1MB) | Preview

Abstract

Understanding the evaporation of water from gas diffusion layers (GDL) is important for polymer electrolyte fuel cell (PEFC) design and operational purposes, particularly for open-cathode air-breathing fuel cells where water removal is purely through evaporation. In this work, water droplet dynamics on the surface of a fuel cell GDL is studied by wettability and thermal characterisation. The droplet maintains a fixed contact diameter (pinned) until there is a transition from non-wetting to wetting regime, after which the contact diameter reduced rapidly until complete evaporation occurs. GDL thermal characterisation reveals that temperature variation encountered across the GDL is due to a change in emissivity and increased thermal gradient across the GDL due to its uneven surface. Droplet thermal characterisation reveals that the droplets have a cooling effect on the surrounding GDL when introduced at room temperature and the cooling effect is more exacerbated with an increase in GDL temperature. This work provides insight into the dynamics of water evaporation on GDLs which could be effective in developing water and heat management strategies in PEFCs, as water droplets are expected to experience similar pinning and cooling effect to that observed in this work within the cathode gas channels of PEFCs. This is particularly relevant to passive open-cathode cells.

Type: Article
Title: Ex-situ characterisation of water droplet dynamics on the surface of a fuel cell gas diffusion layer through wettability analysis and thermal characterisation
Open access status: An open access version is available from UCL Discovery
DOI: 10.1016/j.ijhydene.2017.01.003
Publisher version: https://doi.org/10.1016/j.ijhydene.2017.01.003
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: Contact angle, Water droplet, Gas diffusion layer, Thermal imaging, X-ray computed tomography, Water management
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Chemical Engineering
URI: https://discovery.ucl.ac.uk/id/eprint/10059371
Downloads since deposit
295Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item