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Article
Characterization of saturation-dependent transport properties of gas diffusion layers in PEFCs via 3D flow simulations
| Authors: |
Prasianakis, N.I., Rosén, T., Kang, J. , Eller, J. , Mantzaras, J. , Büchi, F.N. |
| Document Type: |
Conference |
| Pubstate: |
Published |
| Journal: |
21th International Conference on Discrete Simulation of Fluid Dynamics, Bangalore, India (2012) |
| Volume: |
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| Year: |
2012 |
AbstractThe engineering applications related to porous media flows, are of interest in many industrial sectors that span from the chemical and oil industry to the fuel cell development. A much promising eco-friendly solution for future power generation systems is the fuel cell. The study and optimization of the design and of the working efficiency of such devices can be assisted by the use of computational fluid dynamics methods along with X-ray tomographic microscopy (XTM). In our specific example, we examine and characterize the transport properties of the gas diffusion layers (GDLs), which are used in polymer electrolyte fuel cells (PEFCs). The transport properties of this porous material can change due to compression, or due to the presence of liquid water under normal operating conditions of the fuel cell [1,2]. A 3D lattice Boltzmann (LB) model with twenty-seven discrete velocities (D3Q27) is analysed in detail and used in simulating the flow through samples that have been obtained via in-situ XTM at the Swiss Light Source (SLS) facility of Paul Scherrer Institut. Values of permeability and relative effective diffusivity are calculated for different saturation levels and power-law relationships can be derived. Simulation results are also compared to other numerical tools and to experimental values where available. By construction, the model is not restricted in simulating flows that belong to the Darcy-law regime such that a multitude of flow problems and setups can be solved. [1] N.I. Prasianakis, T. Rosén, J. Kang, J. Eller, J. Mantzaras and F. N. Büchi, Simulation of 3D porous media flows with application to polymer electrolyte fuel cells, Commun. Comput. Phys., (in press) (2012). [2] T. Rosén, J. Eller, J. Kang, N.I. Prasianakis, J. Mantzaras and F. N. Büchi, Saturation dependent effective transport properties of PEFC gas diffusion layers, (submitted) (2012).
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