Multi-length scale characterization of compression on metal foam flow-field based fuel cells using X-ray computed tomography and neutron radiography

Advanced search
Browse by:

Department | Year

UCL Theses | Latest

Deposit your research

Multi-length scale characterization of compression on metal foam flow-field based fuel cells using X-ray computed tomography and neutron radiography

Wu, Y; Lu, X; Cho, JIS; Rasha, L; Whiteley, M; Neville, TP; Ziesche, R; ... Brett, DJL; + view all (2021) Multi-length scale characterization of compression on metal foam flow-field based fuel cells using X-ray computed tomography and neutron radiography. Energy Conversion and Management , 230 , Article 113785. 10.1016/j.enconman.2020.113785. Green open access

[thumbnail of Wu_compressed metal foam_revised.pdf]

Preview

Text
Wu_compressed metal foam_revised.pdf - Accepted Version
Download (2MB) | Preview

Abstract

The mechanical compression of metal foam flow-field based polymer electrolyte fuel cells (PEFCs) is critical in determining the interfacial contact resistance with gas diffusion layers (GDLs), reactant flow and water management. The distinct scale between the pore structure of metal foams and the entire flow-field warrant a multi-length scale characterization that combines ex-situ tests of compressed metal foam samples and in-operando analysis of operating PEFCs using X-ray computed tomography (CT) and neutron radiography. An optimal ‘medium’ compression was found to deliver a peak power density of 853 mW cm−2. The X-ray CT data indicates that the compression process significantly decreases the mean pore size and narrows the pore size distribution of metal foams. Simulation results suggest compressing metal foam increases the pressure drop and gas velocity, improving the convective liquid water removal. This is in agreement with the neutron imaging results that demonstrates an increase in the mass of accumulated liquid water with minimum compression compared to the medium and maximum compression cases. The results show that a balance between Ohmic resistance, water removal capacity and parasitic power is imperative for the optimal performance of metal foam based PEFCs.

Type:	Article
Title:	Multi-length scale characterization of compression on metal foam flow-field based fuel cells using X-ray computed tomography and neutron radiography
Open access status:	An open access version is available from UCL Discovery
DOI:	10.1016/j.enconman.2020.113785
Publisher version:	https://doi.org/10.1016/j.enconman.2020.113785
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:	Fuel cell; Compression effect; Metal foam microstructure; Neutron radiography; X-ray CT
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/10120927