Numerical study of cell performance and local transport phenomena in PEM fuel cells with various flow channel area ratios

The objective of this research is to analyze the effects of vibration on the performance of hydrogen PEM fuel cells. It has been reported that if the liquid water transport across the gas diffusion layer (GDL) changes, so does the overall cell performance. Since many fuel cells operate under a vibrating environment –as in the case of automotive applications, this may influence the liquid water concentration across the GDL at different current densities, affecting the overall fuel cell performance. The problem was developed in two main steps. First, the basis for an analytical model was established using current models for water transport in porous media. Then, a series of experiments were carried, monitoring the performance of the fuel cell for different parameters of oscillation. For sinusoidal vibration at 10, 20 and 50Hz (2 g of magnitude), a decrease in the fuel cell performance by 2.2%, 1.1% and 1.3% was recorded when compared to operation at no vibration respectively. For 5 g of magnitude, the fuel cell reported a drop of 5.8% at 50 Hz, whereas at 20 Hz the performance increased by 1.3%. Although more extensive experimentation is needed to identify a relationship between magnitude and frequency of vibration affecting the performance of the fuel cell as well as a throughout examination of the liquid water formation in the cathode, this study shows that sinusoidal vibration, overall, affects the performance of PEM fuel cells.

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Effects of Geometrical Parameters on Improving the Transversal Mass Transport in PEM Fuel Cells

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2006-98189 ◽

2006 ◽

Author(s):

Yanxia Zhao ◽

Renwei Mei ◽

James F. Klausner

Keyword(s):

Fuel Cells ◽

Flow Rate ◽

Fluid Transport ◽

Polymer Electrolyte Membrane ◽

Pem Fuel Cells ◽

Gas Diffusion ◽

Flow Channel ◽

Geometrical Parameters ◽

Electrolyte Membrane ◽

Transversal Flow

A computational model using Lattice Boltzmann Equation (LBE) method is employed to investigate the fluid transport on the anode side of Polymer Electrolyte Membrane (PEM) fuel cells, with an emphasis on mass transfer enhancement. A 3-dimensional LBE code is developed to solve the flows in the channel and the porous media in the gas diffusion layer (GDL) simultaneously. Multiple flow enhancers (obstructions in the flow channel) are placed in the channel to enhance the transversal flow across the GDL. The mass flow rate, the velocity field and the pressure distribution are analyzed. The effects of flow enhancers are assessed. The results show that the transversal flow across the GDL is enhanced by placing flow enhancers in the channel. Increasing flow enhancer size can significantly increase the transversal flow rate, with high pressure-loss through the flow channel. The results also demonstrate that the location of flow enhancers in the flow channel have a remarkable impact on the transversal flow rate. The transversal flow rate increases as the GDL porosity increases.

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Numerical Investigation on the Impact of Membrane Thickness on Transport Phenomena in PEM Fuel Cells

International Journal of Electrochemical Science ◽

10.20964/2020.05.15 ◽

2020 ◽

pp. 4138-4147

Author(s):

Shian Li ◽

Keyword(s):

Fuel Cells ◽

Numerical Investigation ◽

Transport Phenomena ◽

Pem Fuel Cells ◽

Membrane Thickness ◽

The Impact

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