Effect of fiber curvature on gas diffusion layer two-phase dynamics of proton exchange membrane fuel cells
Yang, Danan LU ; Andersson, Martin LU and Garg, Himani LU
(2024)
In International Journal of Hydrogen Energy
85.
p.635-651
- Abstract
Both straight and curved carbon fibers are widely used in various commercial gas diffusion layer (GDL) fabrications. The effect of the different carbon fiber curvatures on two-phase flow dynamics within the cathode GDLs of proton exchange membrane fuel cells remains unclear. In this study, we investigate liquid transport in three types of GDLs with varying fiber curvatures using the two-phase volume of fluid simulations in OpenFOAM. For the first time, a rod periodic surface model is combined with a layer-by-layer fiber stacking strategy, to stochastically reconstruct GDL structures while incorporating crucial parameters from physical (experimental) GDLs. A grid independence study and model validation are conducted. Following pore... (More)
Both straight and curved carbon fibers are widely used in various commercial gas diffusion layer (GDL) fabrications. The effect of the different carbon fiber curvatures on two-phase flow dynamics within the cathode GDLs of proton exchange membrane fuel cells remains unclear. In this study, we investigate liquid transport in three types of GDLs with varying fiber curvatures using the two-phase volume of fluid simulations in OpenFOAM. For the first time, a rod periodic surface model is combined with a layer-by-layer fiber stacking strategy, to stochastically reconstruct GDL structures while incorporating crucial parameters from physical (experimental) GDLs. A grid independence study and model validation are conducted. Following pore network analysis of pore size distribution and connectivity, we study the time-varying GDL total and local water saturation and capillary pressure. Despite maintaining similar layer and bulk porosity, increased fiber curvature enhances pore connectivity but raises water saturation and capillary pressure, increasing the risk of flooding. Additionally, droplets in gas channels with straight-fiber GDLs are larger and have slower movement than those in curved-fiber GDLs. Fiber curvature inversely affects drainage capacity in GDLs and connected channels. With comparable water saturation and capillary pressure, curved-fiber GDLs exhibit lower discrepancies, suggesting improved uniformity in water distribution.
(Less)
- author
- Yang, Danan
LU
; Andersson, Martin
LU
and Garg, Himani
LU
- organization
- publishing date
- 2024-10-04
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Capillary pressure, Curved and straight carbon fiber, Gas diffusion layer reconstruction, Pore network, Volume of fluid method, Water saturation
- in
- International Journal of Hydrogen Energy
- volume
- 85
- pages
- 17 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:85202191910
- ISSN
- 0360-3199
- DOI
- 10.1016/j.ijhydene.2024.08.307
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2024 The Author(s)
- id
- 2125dfe1-2e98-47f1-b2e2-bcf0dbeddf5a
- date added to LUP
- 2024-09-05 16:59:24
- date last changed
- 2024-09-06 09:58:54
@article{2125dfe1-2e98-47f1-b2e2-bcf0dbeddf5a,
abstract = {{<p>Both straight and curved carbon fibers are widely used in various commercial gas diffusion layer (GDL) fabrications. The effect of the different carbon fiber curvatures on two-phase flow dynamics within the cathode GDLs of proton exchange membrane fuel cells remains unclear. In this study, we investigate liquid transport in three types of GDLs with varying fiber curvatures using the two-phase volume of fluid simulations in OpenFOAM. For the first time, a rod periodic surface model is combined with a layer-by-layer fiber stacking strategy, to stochastically reconstruct GDL structures while incorporating crucial parameters from physical (experimental) GDLs. A grid independence study and model validation are conducted. Following pore network analysis of pore size distribution and connectivity, we study the time-varying GDL total and local water saturation and capillary pressure. Despite maintaining similar layer and bulk porosity, increased fiber curvature enhances pore connectivity but raises water saturation and capillary pressure, increasing the risk of flooding. Additionally, droplets in gas channels with straight-fiber GDLs are larger and have slower movement than those in curved-fiber GDLs. Fiber curvature inversely affects drainage capacity in GDLs and connected channels. With comparable water saturation and capillary pressure, curved-fiber GDLs exhibit lower discrepancies, suggesting improved uniformity in water distribution.</p>}},
author = {{Yang, Danan and Andersson, Martin and Garg, Himani}},
issn = {{0360-3199}},
keywords = {{Capillary pressure; Curved and straight carbon fiber; Gas diffusion layer reconstruction; Pore network; Volume of fluid method; Water saturation}},
language = {{eng}},
month = {{10}},
pages = {{635--651}},
publisher = {{Elsevier}},
series = {{International Journal of Hydrogen Energy}},
title = {{Effect of fiber curvature on gas diffusion layer two-phase dynamics of proton exchange membrane fuel cells}},
url = {{http://dx.doi.org/10.1016/j.ijhydene.2024.08.307}},
doi = {{10.1016/j.ijhydene.2024.08.307}},
volume = {{85}},
year = {{2024}},
}