Three-dimensional numerical analysis of PEM fuel cells with straight and wave-like gas flow fields channels

In this paper we analyze the three-dimensional flow field in anode and cathode gas channels of polymer electrolyte membrane (PEM) fuel cells operating at high temperature (T >100 °C). Different gas flow channel designs (pin-type, parallel channels, comb-tipe and multiple serpentine), as well as different channel sections (squared, trapezoidal and rounded with different curvature radii) are evaluated in function of some relevant parameters. The analysis is performed accounting for overall pressure losses, gas distribution over the electrode area and residence time with focus on channel hydraulic diameter, active surface ratio, gas path. Differences with low temperature (LT) PEM fuel cell design are also adressed. The investigation is conducted by means of 3D-CFD softwares and the results of our simulations are compared to experimental data in literature.

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Three-Dimensional Simulations of Transient Response of PEM Fuel Cells

Volume 6: Energy Systems: Analysis, Thermodynamics and Sustainability ◽

10.1115/imece2007-42146 ◽

2007 ◽

Cited By ~ 1

Author(s):

Serhat Yesilyurt

Keyword(s):

Fuel Cells ◽

Gas Flow ◽

Stokes Equations ◽

Three Dimensional ◽

Pem Fuel Cells ◽

Gas Diffusion ◽

Load Pressure ◽

Gas Diffusion Layers ◽

Diffusion Layers ◽

Flow Channels

Transients have utmost importance in the lifetime and performance degradation of PEM fuel cells. Recent studies show that cyclic transients can induce hygro-thermal fatigue. In particular, the amount of water in the membrane varies significantly during transients, and determines the ionic conductivity and the structural properties of the membrane. In this work, we present three-dimensional time-dependent simulations and analysis of the transport in PEM fuel cells. U-sections of anode and cathode serpentine flow channels, anode and cathode gas diffusion layers, and the membrane sandwiched between them are modeled using incompressible Navier-Stokes equations in the gas flow channels, Maxwell-Stefan equations in the channels and gas diffusion layers, advection-diffusion-type equation for water transport in the membrane and Ohm’s law for ionic currents in the membrane and electric currents in gas diffusion electrodes. Transient responses to step changes in load, pressure and the relative humidity of the cathode are obtained from simulations, which are conducted by means of a third party finite-element package, COMSOL.

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Experimental Study and Comparison of Various Designs of Gas Flow Fields to PEM Fuel Cells and Cell Stack Performance

Frontiers in Energy Research ◽

10.3389/fenrg.2014.00002 ◽

2014 ◽

Vol 2 ◽

Cited By ~ 28

Author(s):

Hong Liu ◽

Peiwen Li ◽

Daniel Juarez-Robles ◽

Kai Wang ◽

Abel Hernandez-Guerrero

Keyword(s):

Experimental Study ◽

Fuel Cells ◽

Gas Flow ◽

Flow Fields ◽

Pem Fuel Cells

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Three-dimensional numerical analysis of proton exchange membrane fuel cells (PEMFCs) with conventional and interdigitated flow fields

Journal of Power Sources ◽

10.1016/j.jpowsour.2004.05.010 ◽

2004 ◽

Vol 136 (1) ◽

pp. 1-9 ◽

Cited By ~ 109

Author(s):

Guilin Hu ◽

Jianren Fan ◽

Song Chen ◽

Yongjiang Liu ◽

Kefa Cen

Keyword(s):

Fuel Cells ◽

Numerical Analysis ◽

Proton Exchange Membrane ◽

Three Dimensional ◽

Flow Fields ◽

Proton Exchange ◽

Exchange Membrane

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New Conceptual Gas Distributor With Mass Transfer Enhancing Function in Polymer Electrolyte Fuel Cells

2nd International Conference on Fuel Cell Science, Engineering and Technology ◽

10.1115/fuelcell2004-2521 ◽

2004 ◽

Author(s):

P. W. Li ◽

S. P. Chen ◽

M. K. Chyu

Keyword(s):

Mass Transfer ◽

Fuel Cells ◽

Polymer Electrolyte ◽

Gas Flow ◽

Flow Fields ◽

Pem Fuel Cells ◽

Polymer Electrolyte Fuel Cells ◽

Proton Exchange ◽

Membrane Electrode ◽

Sharp Drop

A new conceptual structure of the gas distributors in polymer electrolyte fuel cells (PEFC) or proton exchange membrane (PEM) fuel cells is developed in this work. Basically, instead of partitioned channels and non-interrupted walls, the proposed new gas distributors make use of discretized elements as the current collector in the flow fields, which can help to enhance the mass transfer in the gas flow fields while maintaining the function of transmitting current out of the fuel cell. Experimental operation without external humidification of the reactant gases for single PEM fuel cells and cell stacks using conventional and the currently presented gas distributors were conducted for comparison and verification. It was found that the maximum operational cell current, beyond which there is a sharp drop of the cell voltage, could be significantly improved when using the currently proposed gas distributors and the same membrane-electrode-assembly (MEA) sheets. Correspondingly, the output electrical power can have at least 11 percent increment for the operation with free-convective airflow and around 50 percent increment for the operation with forced convective airflow.

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